A light generating system

Abstract

A light generating system (1) comprising a first LED light source (3) configured to emit first blue LED light (4), a first phosphor element (5) configured to convert the first blue LED light (4) into first red converted light (6), a second LED light source (7) configured to emit second blue LED light (8), the first phosphor element further being configured to convert the second blue LED light (8) into second red converted light (9), a first dichroic mirror (10) arranged and configured to combine the first red converted light (6) and the second red converted light (9), a third LED light source (11) configured to emit third blue LED light (12), a fourth LED light source (13) configured to emit fourth blue LED light (14), a second phosphor element (15) configured to convert the fourth blue LED light (14) into first green converted light (16), and one or more second dichroic mirrors (17; 171, 172) arranged downstream of the third LED light source (11) and the second phosphor element (15). The first dichroic mirror (10) and the one or more second dichroic mirrors (17; 171, 172) are configured to, in combination, combine the first red converted light (6), the second red converted light (9), the third blue LED light (12), and the first green converted light (16), to form system light (2).

Description

[0001] A light generating system

[0002] FIELD OF THE INVENTION

[0003] The invention relates to a light generating system configured to, in operation, emit system light. The invention further relates to a lamp or a luminaire comprising such a light generating system.

[0004] 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.

[0005] As used herein, the term “green light” is intended to refer to light with a peak wavelength falling within the wavelength interval of 490 nm to 560 nm.

[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 “red light” is intended to refer to light with a peak wavelength falling within the wavelength interval of 600 to 700 nm.

[0008] As used herein, the terms “upstream” and “downstream” are intended to be understood relative to the direction of propagation of light through the light generation 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.

[0009] As used herein, the term “LED light source” is intended to refer to any light source comprising one or more LEDs, including one or more LEDs without any additional optics.

[0010] As used herein, the term “LED” is intended to encompass light emitting diodes, laser diodes and super luminescent diodes.

[0011] BACKGROUND OF THE INVENTION

[0012] High brightness LED light generating systems are used in various applications such as projection and stage lighting. It is desired to improve the brightness and / or color quality of the system light emitted by such a system.

[0013] US 2022 / 0177719 Al discloses narrow band emission phosphor materials, and further discloses LED packages including a light source optically connected or radiationally coupled to a color conversion film, which includes narrow band emission phosphors. Optically or radiationally coupled or connected means that radiation from the light source is able to excite the phosphor material in the color conversion film and the color conversion film is able to emit light in response to the excitation by the radiation. The color conversion film may be disposed on at least a part or portion of the light source or may be located remotely at a distance from the light source.

[0014] US11042080B2 discloses a light source module having first to third light sources, respectively providing first, second and third light, first and second wavelength conversion layers, first and second auxiliary light sources, respectively providing first and second auxiliary light, and a dichroic member. The first wavelength conversion layer is excited by the first light and the first auxiliary light from different sides to generate a first conversion light. The second wavelength conversion layer is excited by the second light and the second auxiliary light from different sides to generate a second conversion light. The dichroic member allows the first and second auxiliary lights to transmit therethrough and reflects the first and second conversion lights. The third light transmits through the dichroic member. The first and second conversion lights and the third light are different in wavelength ranges and combined to form an illumination light.

[0015] US2021 / 373429A1 discloses a light engine projection apparatus, comprising a first green light device configured to emit a green light beam, a first blue light device configured to emit a blue light beam, and a first red light device configured to emit a red light beam. A first beam combiner is configured to combine at least two light beams from at least two light devices from a same light collimation channel so as to form a co-axial light path. The first beam combiner comprises at least one wedged dichroic mirror or a diffraction grating plate.

[0016] However, conventional high brightness LED light generating systems provide white light with an inferior brightness and / or color quality. It is therefore desired to provide a LED light generating system with an improved brightness and / or an improved color quality of the system light emitted by such a system.

[0017] SUMMARY OF THE INVENTION

[0018] It is an object of the present invention to overcome this problem, and to provide a LED light generating system with which the brightness and / or the color quality of the system light emitted by such a system is improved. According to a first aspect of the invention, this and other objects are achieved by means of a light generating system configured to, in operation, emit system light, the light generating system comprising a first LED light source configured to, in operation, emit first blue LED light, a first phosphor element being arranged downstream of the first LED light source and being configured to, at least partly, convert the first blue LED light into first red converted light, a second LED light source configured to, in operation, emit second blue LED light, wherein the first phosphor element is arranged downstream of the second LED light source, and wherein the first phosphor element is further configured to, at least partly, convert the second blue LED light into second red converted light, a first dichroic mirror arranged between the first phosphor element and the second LED light source and configured to combine the first red converted light and the second red converted light, wherein the first dichroic mirror is transparent for the second blue LED light and reflective for the first red converted light and the second red converted light, or wherein the first dichroic mirror is reflective for the second blue LED light and transparent for the first red converted light and the second red converted light, a third LED light source configured to, in operation, emit third blue LED light, a fourth LED light source configured to, in operation, emit fourth blue LED light, a second phosphor element being arranged downstream of the fourth LED light source and being configured to, at least partly, convert the fourth blue LED light into first green converted light, and one or more second dichroic mirrors arranged downstream of the third LED light source and the second phosphor element, wherein the one or more second dichroic mirrors is / are transparent for the third blue LED light and reflective for the first green converted light, or wherein the one or more second dichroic mirrors is / are reflective for the third blue LED light and transparent for the first green converted light, wherein the first dichroic mirror and the one or more second dichroic mirrors are configured to, in combination, combine the first red converted light, the second red converted light, the third blue LED light, and the first green converted light to form the system light, and wherein the system light is white light having a correlated color temperature in a range from 2000K to 9000K and a color rendering index of at least 70.

[0019] Thereby, a LED light generating system with which the brightness and / or the color quality of the system light emitted by such a system is improved.

[0020] The color rendering index may be at least 80, preferably at least 85, or most preferably at least 88. The white light may have a correlated color temperature in a range from 2700K to 6500K (for general lighting applications) or from 6500K to 9000K (for special lighting applications such as stage lighting).

[0021] The white light may have a color point within 12 SDCM from the BBL, more preferably within 10 SDCM from the BBL, most preferably within 10 SDCM from the BBL.

[0022] The first phosphor element may further be configured to fully convert the second blue LED light into second red converted light.

[0023] The first phosphor element may be configured to fully convert the first blue LED light into first red converted light.

[0024] The second phosphor element may further be configured to fully convert the fourth blue LED light into first green converted light.

[0025] The second phosphor element may be arranged upstream of the first dichroic mirror, and the first dichroic mirror may be configured to combine the first red converted light, the second red converted light, and the first green converted light.

[0026] The second phosphor element may be arranged downstream of the first dichroic mirror, and the one or more second dichroic mirrors is / are configured to combine the first red converted light, the second red converted light, and the first green converted light.

[0027] The LED light generating system may further comprise one or more of (i) a first optical element arranged downstream of the first phosphor element and upstream the first dichroic mirror and configured to collimate the first red converted light and the second red converted light, (ii) a second optical element arranged downstream of the second LED light source and configured to collimate the second blue LED light, (iii) a third optical element arranged downstream of the third LED light source and configured to collimate the third blue LED light, and (iv) a fourth optical element arranged downstream of the second phosphor element and configured to collimate the first green converted light.

[0028] Thereby, a LED light generating system with which particularly the brightness of the system light emitted by such a system is improved further. Furthermore, the resulting system light becomes more uniform.

[0029] The LED light generating system further comprises a fifth LED light source configured to, in operation, emitting first red LED light having a peak emission wavelength, 5, being at least 10 nm larger or at least 10 nm smaller than a peak emission wavelength, I, X2, of both the first red converted light and the second red converted light, and wherein the first dichroic mirror and the one or more second dichroic mirrors are configured to, in combination, combine the first red converted light, the second red converted light, the third blue LED light, the first green converted light, and the first red LED light to form the system light.

[0030] In an embodiment, the first dichroic mirror further is arranged downstream of the fifth LED light source, wherein the first dichroic mirror further is transparent for the first red LED light and reflective for the first red converted light and the second red converted light, or wherein the first dichroic mirror further is reflective for the first red LED light and transparent for the first red converted light and the second red converted light, wherein the one or more second dichroic mirrors further is / are arranged downstream of the fifth LED light source and is / are reflective for the first red LED light or are transparent for the first red LED light.

[0031] Thereby, a LED light generating system with which particularly the color quality of the system light emitted by such a system is improved further. Furthermore, a combination of the fifth LED light source emitting first red LED light and using the phosphor of the "KSiF class" is possible because they are both narrow band red emitters.

[0032] The peak emission wavelength, 5, may be at least at least 15 nm, or at least 20 nm, or at least 25 nm, larger than a peak emission wavelength, I, 2, of both the first red converted light and the second red converted light.

[0033] The LED light generating system may further comprise a fifth optical element arranged downstream of the fifth LED light source and configured to collimate the first red LED light.

[0034] Thereby, a LED light generating system with which particularly the brightness of the system light emitted by such a system is improved further. Furthermore, the resulting system light becomes more uniform.

[0035] The LED light generating system may further comprise a sixth LED light source configured to, in operation, emit fifth blue LED light, wherein the second phosphor element is arranged downstream of the sixth LED light source, and wherein the second phosphor element is further configured to, at least partly, convert the fifth blue LED light into second green converted light, wherein the one or more second dichroic mirrors further is / are arranged downstream of the sixth LED light source, and wherein the one or more second dichroic mirrors further is / are transparent for the fifth blue light and reflective for the second green converted light, or wherein the one or more second dichroic mirrors further is / are reflective for the fifth blue light and transparent for the second green converted light, wherein the first dichroic mirror and the one or more second dichroic mirrors are configured to, in combination, combine the first red converted light, the second red converted light, the third blue LED light, the first green converted light, the second green converted light, and where provided the first red LED light to form the system light.

[0036] Thereby, a LED light generating system with which the brightness and / or the color quality of the system light emitted by such a system is improved.

[0037] The second phosphor element may further be configured to fully convert the fifth blue LED light into second green converted light.

[0038] Any one or more of the following may apply: (i) the LED light generating system may further comprise a sixth optical element arranged downstream of the sixth LED light source and configured to collimate the fifth blue LED light, and (ii) the fourth optical element may further be configured to collimate the second green converted light.

[0039] Thereby, a LED light generating system with which particularly the brightness of the system light emitted by such a system is improved further. Furthermore, the resulting system light becomes more uniform.

[0040] The LED light generating system may further comprise a seventh LED light source configured to, in operation, emit first violet LED light, a third phosphor element, the third phosphor element being arranged downstream of the seventh LED light source and being configured to, at least partly, convert the first violet LED light into first blue converted light, and a third dichroic mirror arranged downstream of the seventh LED light source, the third dichroic mirror being reflective for the first blue converted light, or the third dichroic mirror being transparent for the first blue converted light, wherein the first dichroic mirror and the one or more second dichroic mirror further are arranged downstream of the third phosphor element and further are transparent for the first blue converted light, and wherein the first dichroic mirror, the one or more second dichroic mirrors, and the third dichroic mirror are configured to, in combination, combine the first red converted light, the second red converted light, the third blue LED light, the first green converted light, the first blue converted light, where provided the second green converted light, and where provided the first red LED light to form the system light.

[0041] Thereby, a LED light generating system with which the brightness and / or the color quality of the system light emitted by such a system is improved.

[0042] The third phosphor element may further be configured to fully convert the first violet LED light into first blue converted light.

[0043] The LED light generating system may further comprise a seventh optical element arranged downstream of the third phosphor element and upstream of the third dichroic mirror and configured to collimate the first blue converted light. Thereby, a LED light generating system with which particularly the brightness of the system light emitted by such a system is improved further. Furthermore, the resulting system light becomes more uniform.

[0044] The LED light generating system may further comprise an eighth LED light source configured to, in operation, emit second violet LED light, wherein the third phosphor element is arranged downstream of the eighth LED light source, and wherein the third phosphor element further is configured to, at least partly, convert the second violet LED light into second blue converted light, wherein the third dichroic mirror further is arranged downstream of the eighth LED light source, and wherein the third dichroic mirror further is transparent for the second violet LED light and reflective for the second blue converted light, or wherein the third dichroic mirror further is reflective for the second violet LED light and transparent for the second blue converted light, wherein the first dichroic mirror, the one or more second dichroic mirrors, and the third dichroic mirror are configured to, in combination, combine the first red converted light, the second red converted light, the third blue LED light, the first green converted light, the first blue converted light, the second blue converted light, where provided the second green converted light, and where provided the first red LED light to form the system light.

[0045] Thereby, a LED light generating system with which particularly the color quality of the system light emitted by such a system is improved further.

[0046] The third phosphor element may further be configured to fully convert the second violet LED light into second blue converted light.

[0047] Any one or more of the following may apply: (i) the LED light generating system further comprises an eighth optical element arranged downstream of the eighth LED light source and configured to collimate the second violet LED light, and (ii) the seventh optical element is further configured to collimate the second blue converted light.

[0048] Thereby, a LED light generating system with which particularly the brightness of the system light emitted by such a system is improved further. Furthermore, the resulting system light becomes more uniform.

[0049] The LED light generating system may further comprise a ninth LED light source configured to, in operation, emit third violet LED light, wherein the first dichroic mirror, the one or more second dichroic mirror and the third dichroic mirror further are arranged downstream of the ninth LED light source and further are transparent for the third violet LED light, and wherein the first dichroic mirror, the one or more second dichroic mirrors, and the third dichroic mirror are configured to, in combination, combine the first red converted light, the second red converted light, the third blue LED light, the first green converted light, the third violet LED light, where provided the second green converted light, where provided the first blue converted light, where provided the second blue converted light, and where provided, the first red LED light to form the system light.

[0050] Thereby, a LED light generating system with which the brightness and / or the color quality of the system light emitted by such a system is improved.

[0051] The LED light generating system may further comprise a ninth optical element arranged downstream of the ninth LED light source and configured to collimate the third violet LED light.

[0052] Thereby, a LED light generating system with which particularly the brightness of the system light emitted by such a system is improved further. Furthermore, the resulting system light becomes more uniform.

[0053] Any one or more of the first, second, third, fourth, fifth, sixth, seventh, eighth and ninth optical elements may be a lens.

[0054] The first phosphor element may comprise a phosphor of the type M’xM2- 2xAX6 doped with tetravalent manganese, wherein M’ comprises an alkaline earth cation, wherein 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, F.

[0055] Thereby, the first and second red converted light has a good red color quality. Furthermore, such phosphors are stable and efficient phosphors. The latter is due to the relative narrow emission band of this type of phosphor.

[0056] In embodiments, the first phosphor element may comprise a KSiF-type phosphor.

[0057] The second phosphor element may comprise a phosphor 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.

[0058] Such phosphors are stable and efficient phosphors and can be applied directly on top of LEDs with good lifetime.

[0059] The third phosphor may comprise a BOSE phosphor.

[0060] Thereby, first and second green converted light with a good green appearance is provided for. Furthermore, such phosphors are stable and efficient phosphors and can be applied directly on top of LEDs with good lifetime. In embodiments, the light generating system may further comprise a controller configured to individually control the first LED light source, the second LED light source, the third LED light source, the fourth LED light source, and where provided the fifth LED light source, and where provided the sixth LED light source, and where provided the seventh LED light source, and where provided the eight LED light source, and where provided the ninth LED light source e.g. for varying one or more of the intensity, color rendering index and correlated color temperature (e.g. with a difference of at least 500K or at least lOOOK) of the system light.

[0061] The invention further relates to a lamp or a luminaire comprising a light generating system according to the invention.

[0062] The lamp or the luminaire may, thanks to the light generating system, provide system light with an improved brightness and / or an improved color quality.

[0063] The lamp or luminaire may be any type of lamp and luminaire, but particularly a stage lighting luminaire or fixture.

[0064] It is noted that the invention relates to all possible combinations of features recited in the claims.

[0065] BRIEF DESCRIPTION OF THE DRAWINGS

[0066] 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.

[0067] Fig. 1 schematically shows an embodiment of a light generating system according to the invention.

[0068] Fig. 2 schematically shows another embodiment of a light generating system according to the invention.

[0069] Fig. 3 schematically shows another embodiment of a light generating system according to the invention.

[0070] Fig. 4 schematically shows another embodiment of a light generating system according to the invention.

[0071] Fig. 5 schematically shows another embodiment of a light generating system according to the invention.

[0072] Figs. 6-13 schematically shows further possible embodiments of a light generating system according to the invention. Fig. 14 shows a graph of the intensity in arbitrary units as a function of the wavelength of emission Em and excitation Ex, respectively, for a KSiF phosphor, and for red light emitted by a LED emitting direct red light in dashed line.

[0073] Fig. 15 shows a graph of the intensity in arbitrary units as a function of the wavelength of emission Em and excitation Ex, respectively, for a LuAG phosphor.

[0074] 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.

[0075] DETAILED DESCRIPTION

[0076] 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.

[0077] Fig. 1 schematically shows an embodiment of a light generating system 1 according to the invention. Generally, and irrespective of the embodiment, the light generating system 1 comprises a first LED light source 3, a first phosphor element 5 arranged downstream of the first LED light source 3, a second LED light source 7, a first dichroic mirror 10, a third LED light source 11, a fourth LED light source 12, a second phosphor element 15 arranged downstream of the fourth LED light source 12, and one or more second dichroic mirrors 17, 171, 172.

[0078] The first LED light source 3 is configured to, in operation, emit first blue LED light 4 (cf. Figs. 6-13). The first LED light source 3 may be at least partially and optionally fully covered by the first phosphor element 5. The first phosphor element 5 is arranged downstream of the first LED light source 3. The first phosphor element 5 is configured to, at least partly and optionally fully, convert the first blue LED light 4 into first red converted light 6. The first phosphor element 5 comprises a phosphor of the type M’xM2-2xAX6 doped with tetravalent manganese, wherein M’ comprises an alkaline earth cation, M comprises an alkaline cation, and x 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 second LED light source 7 is configured to, in operation, emit second blue LED light 8. The first phosphor element 5 is arranged downstream of the second LED light source 7. The first phosphor element 5 is configured to, at least partly and optionally fully, convert the second blue LED light 8 into second red converted light 9. In other words, the second LED light source 7 is arranged such as to pump the first phosphor element 5 such that the second blue LED light is converted into second red converted light 9.

[0079] The first dichroic mirror 10 is arranged between the first LED light source 3 and the second LED light source 7. More particularly, the first dichroic mirror 10 is arranged between the first phosphor element 5 and the second LED light source 7. The first dichroic mirror 10 is configured to combine the first red converted light 6 and the second red converted light 9. The first dichroic mirror 10 is transparent for the second blue LED light 8 and reflective for the first red converted light 6 and the second red converted light 9. Alternatively, the first dichroic mirror 10 is reflective for the second blue LED light 8 and transparent for the first red converted light 6 and the second red converted light 9.

[0080] The third LED light source 11 is configured to, in operation, emit third blue LED light 12.

[0081] The fourth LED light source 13 is configured to, in operation, emit fourth blue LED light 14 (cf. Figs. 6-13). The fourth LED light source 13 may be at least partially and optionally fully covered by the second phosphor element 15. The second phosphor element 15 is arranged downstream of the fourth LED light source 13. The second phosphor element 15 is configured to, at least partly and optionally fully, convert the fourth blue LED light 14 into first green converted light 16. The second phosphor element 51 comprises a phosphor 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.

[0082] The one or more second dichroic mirrors 171, 172 are arranged downstream of the third LED light source 11 and the fourth LED light source 13. More particularly, the one or more second dichroic mirrors 171, 172 are arranged downstream of the third LED light source 11 and the second phosphor element 15. In the embodiment shown in Fig. 1 two second dichroic mirrors 171, 172 are provided. In the embodiment shown in Fig. 1 the two second dichroic mirrors 171, 172 are arranged in the same place and oriented in an angle of 90 degrees to one another. The two second dichroic mirrors 171, 172 are transparent for the third blue LED light 12 and reflective for the first green converted light 16. Alternatively, the two second dichroic mirrors 171, 172 are reflective for the third blue LED light 12 and transparent for the first green converted light 16. In the embodiment shown in Fig. 1, the two second dichroic mirrors 171, 172 are arranged downstream of the first dichroic mirror 10. Further, in the embodiment shown in Fig. 1, the two second dichroic mirrors 171, 172 are configured to combine the third blue LED light 12, the first green converted light 16, and the combined first red converted light 6 and the second red converted light 9.

[0083] Thus, generally, and irrespective of the embodiment, the first dichroic mirror 10 and the one or more second dichroic mirrors 17, 171, 172 are configured to, in combination, combine the first red converted light 6, the second red converted light 9, the third blue LED light 12, and the first green converted light 16 to form the system light 2.

[0084] Thus, in the embodiment shown in Fig. 1, the system light 2 comprises the first red converted light 6, the second red converted light 9, the third blue LED light 12, and the first green converted light 16. Generally, and irrespective of the embodiment, the system light 2 is white light having a correlated color temperature in a range from 2000K to 9000K and a color rendering index of at least 70.

[0085] The light generating system 1 may further comprise one or more optional optical devices or light collimating devices 18-21. The one or more optical devices 18-21 may be lenses.

[0086] A first optical device 18 may be arranged downstream of the first phosphor element 5 and upstream of the first dichroic mirror 10. The first optical device 18 is configured to collimate the first red converted light 6 and the second red converted light 9. A second optical device 19 may be arranged downstream of the second LED light source 7. The second optical device 19 is configured to collimate the second blue LED light 8. A third optical device 20 may be arranged downstream of the third LED light source 11. The third optical device is configured to collimate the third blue LED light 12. A fourth optical device 21 may be arranged downstream of the second phosphor element 15. The second optical device is configured to collimate the first green converted light 16.

[0087] Generally, and irrespective of the embodiment, the light generating system 1 may further comprise an optional controller 42. The controller 42 is configured to individually control one or more of the LED light sources of the light generating system 1. The controller 42 is configured, e.g., to vary one or more of the intensity, color rendering index and correlated color temperature (e.g. with a difference of at least 500K or at least lOOOK) of the system light. The controller may be connected to the LED light sources by a wired or wireless connection. The controller 42 is configured to individually control the first LED light source 3, the second LED light source 7, the third LED light source 11, the fourth LED light source 13, and where provided the fifth LED light source 22, and where provided the sixth LED light source 25, and where provided the seventh LED light source 29, and where provided the eight LED light source 35, and where provided the ninth LED light source 39.

[0088] Referring now to Fig. 2, a schematic view of another light generating system 100 according to the invention is shown. The light generating system 100 differs from the light generating system 1 described above with reference to Fig. 1 in virtue of the following features.

[0089] The light generating system 100 comprises a fifth LED light source 22. The fifth LED light source 22 is configured to, in operation, emit first red LED light 23. The first red LED light 23 has a peak emission wavelength X5 being larger, and particularly more than 10 nm larger, than a peak emission wavelength XI of the first red converted light 6 and being larger, and particularly more than 10 nm larger, than a peak emission wavelength X2 of the second red converted light 9. See also Fig. 14, where the said three peak emission wavelengths XI, X2 and X5 are shown. Alternatively, the first red LED light 23 may have a peak emission wavelength X5 being smaller, and particularly more than 10 nm smaller, than a peak emission wavelength XI of the first red converted light 6 and being smaller, and particularly more than 10 nm smaller, than a peak emission wavelength X2 of the second red converted light 9.

[0090] The first dichroic mirror 10 is further arranged downstream of the fifth LED light source 22. The first dichroic mirror 10 is further transparent for the first red LED light 23 and reflective for the first red converted light 6 and the second red converted light 9. Alternatively, the first dichroic mirror 10 is further reflective for the first red LED light 23 and transparent for the first red converted light 6 and the second red converted light 9.

[0091] Again, two second dichroic mirrors 171, 172 are provided. The two second dichroic mirrors 171, 172 are further arranged downstream of the fifth LED light source 22. The two second dichroic mirrors 171, 172 are further reflective for the first red LED light 23. Alternatively, the two second dichroic mirrors 171, 172 are further transparent for the first red LED light 23. Further, in the embodiment shown in Fig. 2, the two second dichroic mirrors 171, 172 are configured to combine the third blue LED light 12, the first green converted light 16, the combined first red converted light 6 and second red converted light 9, and the first red LED light 23. Thus, the first dichroic mirror 10 and the two second dichroic mirrors 171, 172 are in this embodiment configured to, in combination, combine the first red converted light 6, the second red converted light 9, the third blue LED light 12, the first green converted light 16, and the first red LED light 23 to form the system light 2.

[0092] Thus, in the embodiment shown in Fig. 2, the system light 2 comprises the first red converted light 6, the second red converted light 9, the third blue LED light 12, the first green converted light 16, and the first red LED light 23.

[0093] The light generating system 100 may further comprise an optional fifth optical device or light collimating device 24. The fifth optical device 24 is arranged downstream of the fifth LED light source 22. The fifth optical device 24 is configured to collimate the first red LED light 23. The fifth optical device 24 may be a lens.

[0094] Referring now to Fig. 3, a schematic view of another light generating system 101 according to the invention is shown. The light generating system 101 differs from the light generating systems 1 and 100 described above with reference to Figs. 1 and 2 in virtue of the following features.

[0095] The light generating system 101 comprises a sixth LED light source 25. The sixth LED light source 25 is configured to, in operation, emit fifth blue LED light 26. The second phosphor element 15 is arranged downstream of the sixth LED light source 25. The second phosphor element 15 is configured to, at least partly and optionally fully, convert the fifth blue LED light 26 into second green converted light 17. In other words, the sixth LED light source 25 is arranged such as to pump the second phosphor element 15 such that the fifth blue LED light 26 is converted into second green converted light 27.

[0096] In the embodiment shown in Fig. 3, only one second dichroic mirror 17 is provided. The second dichroic mirror 17 is further arranged downstream of the sixth LED light source 25. The second dichroic mirror 17 is further transparent for the fifth blue light 26 and reflective for the second green converted light 27. Alternatively, the second dichroic mirror 17 is further reflective for the fifth blue light 26 and transparent for the second green converted light 27.

[0097] Also, the light generating system 101 does not comprise any fifth LED light source 22 configured to, in operation, emit first red LED light 23. Nevertheless, it is feasible to provide a light generating system 101 of the type shown in Fig. 3 with a fifth LED light source 22 configured to, in operation, emit first red LED light 23 as described in connection with Fig. 2. In the embodiment shown in Fig. 3, the second dichroic mirror 17 is arranged upstream of the first dichroic mirror 10. The second dichroic mirror 17 is configured to combine the first green converted light 16, the second green converted light 27, and the third blue LED light 12.

[0098] Thus, the first dichroic mirror 10 and the second dichroic mirror 17 are configured to, in combination, combine the first red converted light 6, the second red converted light 9, the third blue LED light 12, the first green converted light 16 and the second green converted light 27 to form the system light 2. In case a fifth LED light source 22 configured to, in operation, emit first red LED light 23 is provided, the first dichroic mirror 10 and the second dichroic mirror 17 are additionally configured to, in combination, combine the first red LED light 23 with the above-mentioned lights 6, 9, 12, 16 and 27 to form the system light 2.

[0099] The light generating system 101 may further comprise an optional sixth optical device or light collimating device 28. The sixth optical device 28 is arranged downstream of the sixth LED light source 25. The sixth optical device is configured to collimate the fifth blue LED light 26. The sixth optical device 28 may be a lens. Furthermore, and where provided, the fourth optical device 21 may further be arranged and configured to collimate the second green converted light 27.

[0100] Referring now to Fig. 4, a schematic view of another light generating system 102 according to the invention is shown. The light generating system 102 differs from the light generating systems 1, 100 and 101 described above with reference to Figs. 1, 2 and 3 in virtue of the following features.

[0101] The light generating system 102 does not comprise any fifth LED light source 22 configured to, in operation, emit first red LED light 23. Nevertheless, it is feasible to provide a light generating system 102 of the type shown in Fig. 4 with a fifth LED light source 22 configured to, in operation, emit first red LED light 23 as described in connection with Fig. 2.

[0102] Furthermore, for the sake of simplicity, the third LED light source 11 configured to, in operation, emit third blue LED light 12, is not shown in Fig. 4.

[0103] The light generating system 102 comprises a seventh LED light source 29. The seventh LED light source 29 is configured to, in operation, emit first violet LED light (not visible on the Figures). A third phosphor element 31 is arranged downstream of the seventh LED light source 29. The seventh LED light source 29 may be at least partially and optionally fully covered by the third phosphor element 31. The third phosphor element 31 is configured to, at least partly and optionally fully, convert the first violet LED light into first blue converted light 32.

[0104] The light generating system 102 further comprises an eighth LED light source 35. The eighth LED light source 35 is configured to, in operation, emit second violet LED light 36. The third phosphor element 31 is arranged downstream of the eighth LED light source 35. The third phosphor element 31 is configured to, at least partly and optionally fully, convert the second violet LED light 36 into second blue converted light 37. In other words, the eighth LED light source 35 is arranged such as to pump the third phosphor element 31 such that the second violet LED light 36 is converted into second blue converted light 37. It is noted that it is also possible to omit the eighth LED light source 35, which is thus optional.

[0105] The light generating system 102 further comprises a third dichroic mirror 33. The third dichroic mirror 33 is arranged downstream of the seventh LED light source 29, and where provided the eighth LED light source 35. The third dichroic mirror 33 is reflective for the first blue converted light 32. In case an eighth LED light source 35 is provided, the third dichroic mirror 33 is further transparent for the second violet LED light 36 and reflective for the second blue converted light 37. Alternatively, the third dichroic mirror 33 is transparent for the first blue converted light 32. In case an eighth LED light source 35 is provided, the third dichroic mirror 33 is then further reflective for the second violet LED light 36 and transparent for the second blue converted light 37.

[0106] In the embodiment shown in Fig. 4, only one second dichroic mirror 17 is provided. In the embodiment shown in Fig. 4, the third dichroic mirror 33 is arranged upstream of the first dichroic mirror 10 and the second dichroic mirror 17. The first dichroic mirror 10 and the second dichroic mirror 17 are arranged downstream of the third phosphor element 31. Therefore, the first dichroic mirror 10 and the second dichroic mirror 17 are further transparent for the first blue converted light 32.

[0107] The third dichroic mirror 33 is configured to combine the first blue converted light 32 and the second blue converted light 37. In case the eighth LED light source 35 is omitted, the third dichroic mirror 33 is simply configured to redirect the first blue converted light 32 towards the second dichroic mirror 17.

[0108] In the embodiment shown in Fig. 4, the second dichroic mirror 17 is arranged upstream of the first dichroic mirror 10. The second dichroic mirror 17 is configured to combine the first green converted light 16, the second green converted light 27, and the combined first and second blue converted light 32, 37. In case the eighth LED light source 35 is omitted, the second dichroic mirror 17 is configured to combine the first green converted light 16, the second green converted light 27, and the first blue converted light 32.

[0109] The first dichroic mirror 10 is configured to combine the combined first and second green converted light 16, 27 and the combined first and second blue converted light 32, 37 with the combined first and second red converted light 6, 9. In case the eighth LED light source 35 is omitted, the second dichroic mirror 17 is configured to combine the combined first and second green converted light 16 and the first blue converted light 32 with the combined first and second red converted light 6, 9.

[0110] Thus, the first dichroic mirror 10, the second dichroic mirror 17, and the third dichroic mirror 33 are configured to, in combination, combine the first red converted light 6, the second red converted light 9, the third blue LED light 12, the first green converted light 16, the second green converted light 27, the first blue converted light 32 and, if an eighth LED light source 35 is provided, the second blue converted light 37, to form the system light 2.

[0111] In case a fifth LED light source 22 configured to, in operation, emit first red LED light 23 is provided, the first dichroic mirror 10, the second dichroic mirror 17, and the third dichroic mirror 33 are additionally configured to, in combination, combine the first red LED light 23 with the above-mentioned lights 6, 9, 12, 16, 27, 32 and 37 to form the system light 2.

[0112] The light generating system 102 may further comprise an optional seventh optical device or light collimating device 34. The seventh optical device 34 is arranged downstream of the third phosphor element 31 and upstream of the third dichroic mirror 33. The seventh optical device 34 is configured to collimate the first blue converted light 32. The seventh optical device 34 may be a lens.

[0113] The light generating system 102 may further comprise an optional eighth optical device or light collimating device 38. The eighth optical device 38 may be arranged downstream of the eighth LED light source 35. The eighth optical device 38 is configured to collimate the second violet LED light 36. The eighth optical device 38 may be a lens. The seventh optical device 34 may, if provided, then further be arranged and configured to collimate the second blue converted light 37.

[0114] Referring now to Fig. 5, a schematic view of another light generating system 103 according to the invention is shown. The light generating system 103 is very similar to the light generating systems 102 shown in Fig. 4 but differs therefrom in virtue of the following features. The light generating system 103 does not comprise any fifth LED light source 22 configured to, in operation, emit first red LED light 23. Nevertheless, it is feasible to provide a LED light generating system 103 of the type shown in Fig. 5 with a fifth LED light source 22 configured to, in operation, emit first red LED light 23 as described in connection with Fig. 2.

[0115] Furthermore, for the sake of simplicity, the third LED light source 11 configured to, in operation, emit third blue LED light 12, is not shown in Fig. 5.

[0116] The light generating system 103 further comprises a ninth LED light source

[0117] 39. The ninth LED light source 39 is configured to, in operation, emit third violet LED light

[0118] 40.

[0119] The ninth LED light source 39 is arranged upstream of the first dichroic mirror 10, the second dichroic mirror 17 and the third dichroic mirror 33. Therefore, the first dichroic mirror 10, the second dichroic mirror 17 and the third dichroic mirror 33 are transparent for the third violet LED light 40.

[0120] The first dichroic mirror 10, the second dichroic mirror 17, and the third dichroic mirror 33 are arranged downstream of the ninth LED light source 39. The first dichroic mirror 10, the second dichroic mirror 17, and the third dichroic mirror 33 are transparent for the third violet light 40. Thus, the first dichroic mirror 10, the second dichroic mirror 17, and the third dichroic mirror 33 are configured to, in combination, combine the first red converted light 6, the second red converted light 9, the third blue LED light 12, the first green converted light 16, the second green converted light 27, the third violet LED light 40, the first blue converted light 32, the second blue converted light 37, and, where provided, the first red LED light 23, to form the system light 2.

[0121] The light generating system 103 may further comprise an optional ninth optical device or light collimating device 41. The ninth optical device 41 may be arranged downstream of the ninth LED light source 39. The ninth optical device 41 is configured to collimate the third violet LED light 40. The ninth optical device 41 may be a lens.

[0122] Figs. 6-13 schematically shows further possible light generating systems 104- 111 according to the invention. It is noted that in all of Figs. 6-13 the optional optical devices are omitted for the sake of simplicity.

[0123] Fig. 6 shows a light generating system 104 being similar to the light generating system 101 described further above and shown in Fig. 3. The light generating system 104 differs from the light generating system 101 in that it does not comprise any sixth LED light source 25, and further in the arrangement and configuration of the first dichroic mirror 10 and the second dichroic mirror 17.

[0124] In the embodiment shown in Fig. 6, the second dichroic mirror 17 is arranged upstream of the first dichroic mirror 10. The first dichroic mirror 10 is configured to combine the first red converted light 6, the second red converted light 9 and the third blue LED light 12. The second dichroic mirror 17 is configured to reflect the third blue LED light 12 and to transmit the first green converted light 16. The second dichroic mirror 17 is configured to combine the first green converted light 16 and the third blue LED light 12.

[0125] Thus, the first dichroic mirror 10 and the second dichroic mirror 17 are configured to, in combination, combine the first red converted light 6, the second red converted light 9, the third blue LED light 12 and the first green converted light 16 to form the system light 2.

[0126] Fig. 7 shows a light generating system 105 being very similar to the light generating system 101 described further above and shown in Fig. 3. The light generating system 105 differs from the light generating system 101 in that it does not comprise any sixth LED light source 25.

[0127] In the embodiment shown in Fig. 7, the second dichroic mirror 17 is arranged upstream of the first dichroic mirror 10. The second dichroic mirror 17 is configured to combine the first green converted light 16 and the third blue LED light 12.

[0128] Thus, the first dichroic mirror 10 and the second dichroic mirror 17 are configured to, in combination, combine the first red converted light 6, the second red converted light 9, the third blue LED light 12 and the first green converted light 16 to form the system light 2.

[0129] Fig. 8 shows a light generating system 106 being very similar to the light generating system 105 described above and shown in Fig. 7, but differing therefrom in virtue of the following.

[0130] In the embodiment shown in Fig. 8, the second dichroic mirror 17 is arranged downstream of the first dichroic mirror 10. The first dichroic mirror 10 is configured to combine the first red converted light 6, the second red converted light 9 and the third blue LED light 12. The second dichroic mirror 17 is configured to reflect the first green converted light 16.

[0131] Thus, the first dichroic mirror 10 and the second dichroic mirror 17 are configured to, in combination, combine the first red converted light 6, the second red converted light 9, the third blue LED light 12 and the first green converted light 16 to form the system light 2.

[0132] Fig. 9 shows a light generating system 107 being very similar to the light generating system 104 described further above and shown in Fig. 6. The light generating system 107 differs from the light generating system 104 in the arrangement and configuration of the first dichroic mirror 10 and the second dichroic mirror 17.

[0133] In the embodiment shown in Fig. 9, the second dichroic mirror 17 is arranged downstream of the first dichroic mirror 10. The first dichroic mirror 10 is configured to combine the first red converted light 6, the second red converted light 9 and the first green converted light 16. The second dichroic mirror 17 is configured to reflect the third blue LED light 12 and to transmit the first green converted light 16, the first red converted light 6, and the second red converted light 9.

[0134] Thus, the first dichroic mirror 10 and the second dichroic mirror 17 are configured to, in combination, combine the first red converted light 6, the second red converted light 9, the third blue LED light 12 and the first green converted light 16 to form the system light 2.

[0135] Fig. 10 shows a light generating system 108 being very similar to the light generating system 100 described further above and shown in Fig. 2. The light generating system 108 differs from the light generating system 102 in that it does not comprise any fifth LED light source 22, and further in the arrangement and configuration of the two second dichroic mirrors 171 and 172.

[0136] In the embodiment shown in Fig. 10, the one second dichroic mirror 171 is arranged downstream of the other second dichroic mirror 172. The second dichroic mirror

[0137] 171 is configured to transmit the first green converted light 16 and to reflect the third blue LED light 12. The second dichroic mirror 171 is configured to combine the first green converted light 16 and the third blue LED light 12. The other second dichroic mirror 172 is configured to reflect the combined third blue LED light 12 and first green converted light 16 and to transmit the first red converted light 6, and the second red converted light 9.

[0138] Thus, the first dichroic mirror 10 and the two second dichroic mirrors 171 and

[0139] 172 are configured to, in combination, combine the first red converted light 6, the second red converted light 9, the third blue LED light 12 and the first green converted light 16 to form the system light 2.

[0140] Fig. 11 shows a light generating system 109 being very similar to the light generating system 108 described above and shown in Fig. 10. The light generating system 109 differs from the light generating system 108 in the configuration of the second dichroic mirror 171.

[0141] In the embodiment shown in Fig. 11, the second dichroic mirror 171 is arranged downstream of the other second dichroic mirror 172. The second dichroic mirror

[0142] 171 is configured to reflect the first green converted light 16 and to transmit the third blue LED light 12. The second dichroic mirror 171 is configured to combine the first green converted light 16 and the third blue LED light 12. The other second dichroic mirror 172 is configured to reflect the combined third blue LED light 12 and first green converted light 16 and to transmit the first red converted light 6, and the second red converted light 9.

[0143] Thus, the first dichroic mirror 10 and the two second dichroic mirrors 171 and

[0144] 172 are configured to, in combination, combine the first red converted light 6, the second red converted light 9, the third blue LED light 12 and the first green converted light 16 to form the system light 2.

[0145] Fig. 12 shows a light generating system 110 being very similar to the light generating systems 108 and 109 described above and shown in Figs. 10 and 11, respectively. The light generating system 110 differs from the light generating systems 108 and 109 in the configuration of the two second dichroic mirrors 171 and 172.

[0146] In the embodiment shown in Fig. 12, the second dichroic mirror 171 is arranged downstream of the other second dichroic mirror 172. The second dichroic mirror

[0147] 171 is configured to reflect the first green converted light 16 and to transmit the first red converted light 6, and the second red converted light 9. The second dichroic mirror 171 is configured to combine the first green converted light 16, the first red converted light 6, and the second red converted light 9.

[0148] The other second dichroic mirror 172 is configured to reflect the third blue LED light 12 and to transmit the combined first green converted light 16, first red converted light 6, and second red converted light 9.

[0149] Thus, the first dichroic mirror 10 and the two second dichroic mirrors 171 and

[0150] 172 are configured to, in combination, combine the first red converted light 6, the second red converted light 9, the third blue LED light 12 and the first green converted light 16 to form the system light 2.

[0151] Finally, Fig. 13 shows a light generating system 111 being very similar to the light generating system 110 described above and shown in Fig. 11. The light generating system 111 differs from the light generating system 110 in the arrangement of the two second dichroic mirrors 171 and 172. In the embodiment shown in Fig. 12, the second dichroic mirror 171 is arranged upstream of the other second dichroic mirror 172. The other second dichroic mirror 172 is configured to reflect the third blue LED light 12 and to transmit the combined first red converted light 6, and second red converted light 9.

[0152] The second dichroic mirror 171 is configured to reflect the first green converted light 16 and to transmit the combined third blue LED light 12, first red converted light 6, and second red converted light 9.

[0153] Thus, the first dichroic mirror 10 and the two second dichroic mirrors 171 and 172 are configured to, in combination, combine the first red converted light 6, the second red converted light 9, the third blue LED light 12 and the first green converted light 16 to form the system light 2.

[0154] Referring now to Figs. 14 to 15, different suitable phosphor elements for a light generating system 1, 100-111 according to the invention will be described.

[0155] Garnet class

[0156] Generally, garnet class phosphors are particularly suitable for use as the second phosphor element 15. Garnet class phosphors are luminescent materials of the type AsBsOn Ce, wherein A in embodiments comprises one or more of Y, La, Gd, Tb and Lu, especially (at least) one or more of Y, Gd, Tb and Lu, and wherein B in embodiments comprises one or more of Al, Ga, In and Sc. Especially, A may comprise one or more of Y, Gd and Lu, such as especially one or more of Y and Lu. Especially, B may comprise one or more of Al and Ga, more especially at least Al, such as essentially entirely Al. Hence, especially suitable luminescent materials are cerium comprising garnet materials. 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.

[0157] Fig. 15 shows a graph of the intensity in arbitrary units as a function of the wavelength of emission (dotted line, Em) and excitation (solid line, Ex), respectively, for one suitable garnet class phosphor, namely a Lutetium Aluminum Garnet (LuAG) phosphor. LuAG phosphors offer performance comparable to YAG phosphor elements. LuAG phosphors may have dominant emission wavelengths ranging from 520nm to 540 nm. LuAG phosphors are generally used in conjunction with red phosphor elements 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 a nitride red phosphor, a high CRI spectrum with Ra above 95 can be achieved. LuAG phosphors are particularly suitable for use as the second phosphor element 15.

[0158] KSiF class

[0159] Generally, KSiF class phosphors are particularly suitable for use as the first phosphor element 5. KSiF class phosphor are luminescent materials 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 cation, for instance comprising one or more of silicon and titanium, wherein X comprises a monovalent anion, at least comprising fluorine.

[0160] 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’xM2-2XAXe , a fraction comprises K+and an optionally remaining fraction comprises one or more other monovalent (alkaline) cations (see also below). In another preferred embodiment, M comprises at least potassium and rubidium. Optionally, the M’XM2- 2XAXe luminescent material has the hexagonal phase. In yet another embodiment, the M’XM2- 2XAXe luminescent material has the cubic phase. For x=0, the composition is M2AX6.

[0161] Relevant alkaline earth cations (M’) are magnesium (Mg), strontium (Sr), calcium (Ca) and barium (Ba), especially one or more of Sr and Ba.

[0162] 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.

[0163] 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).

[0164] 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+).

[0165] 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.

[0166] Fig. 14 shows a graph of the intensity in arbitrary units as a function of the wavelength of emission (dotted line, Em) and excitation (solid line, Ex), 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 element for a backlight, NTSC can be improved to above 100 %. KSiF phosphors are particularly suitable for use as the first phosphor element 5. BOSE class

[0167] A BOSE phosphor is a phosphor comprising alkaline earth orthosilicates doped with europium, or more generally an orthosilicate phosphor. BOSE phosphors are particularly suitable for use as the third phosphor element 31.

[0168] 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

CLAIMS:

1. A light generating system (1) configured to, in operation, emit system light(2), the light generating system comprising: a first LED light source (3) configured to, in operation, emit first blue LED light (4), a first phosphor element (5) being arranged downstream of the first LED light source and being configured to, at least partly, convert the first blue LED light (4) into first red converted light (6), a second LED light source (7) configured to, in operation, emit second blue LED light (8), wherein the first phosphor element is arranged downstream of the second LED light source (7), and wherein the first phosphor element is further configured to, at least partly, convert the second blue LED light into second red converted light (9), a first dichroic mirror (10) arranged between the first phosphor element (5) and the second LED light source (7) and configured to combine the first red converted light (6) and the second red converted light (9), wherein the first dichroic mirror (10) is transparent for the second blue LED light (8) and reflective for the first red converted light (6) and the second red converted light (9), or wherein the first dichroic mirror (10) is reflective for the second blue LED light (8) and transparent for the first red converted light (6) and the second red converted light (9), a third LED light source (11) configured to, in operation, emit third blue LED light (12), a fourth LED light source (13) configured to, in operation, emit fourth blue LED light (14), a second phosphor element (15) being arranged downstream of the fourth LED light source and being configured to, at least partly, convert the fourth blue LED light (14) into first green converted light (16), a fifth LED light source (22) configured to, in operation, emitting first red LED light (23) having a peak emission wavelength ( 5) being at least 10 nm larger or at least 10 nm smaller than a peak emission wavelength ( I, 2) of both the first red converted light (6) and the second red converted light (9), andone or more second dichroic mirrors (17; 171, 172) arranged downstream of the third LED light source (11) and the second phosphor element (15), wherein the one or more second dichroic mirrors (17; 171, 172) is / are transparent for the third blue LED light (12) and reflective for the first green converted light (16), or wherein the one or more second dichroic mirrors (17; 171, 172) is / are reflective for the third blue LED light (12) and transparent for the first green converted light (16), wherein the first dichroic mirror (10) and the one or more second dichroic mirrors (17;171, 172) are configured to, in combination, combine: the first red converted light (6), the second red converted light (9), the third blue LED light (12), and the first green converted light (16), the first red LED light (23), to form the system light (2), and wherein the system light is white light having a correlated color temperature in a range from 2000 K to 9000 K and a color rendering index of at least 70.

2. A light generating system according to any one of the preceding claims and further comprising: a first optical element (18) arranged downstream of the first phosphor element (5) and upstream the first dichroic mirror (10) and configured to collimate the first red converted light (6) and the second red converted light (9), a second optical element (19) arranged downstream of the second LED light source (7) and configured to collimate the second blue LED light (8), a third optical element (20) arranged downstream of the third LED light source (11) and configured to collimate the third blue LED light (12), and a fourth optical element (21) arranged downstream of the second phosphor element (15) and configured to collimate the first green converted light (16).

3. A light generating system according to any one of the above claims, wherein the first dichroic mirror (10) further is arranged downstream of the fifth LED light source (22), wherein the first dichroic mirror (10) further is transparent for the first red LED light (23) and reflective for the first red converted light (6) and the second red converted light (9), or wherein the first dichroic mirror (10) further is reflective for the first red LEDlight (23) and transparent for the first red converted light (6) and the second red converted light (9), and wherein the one or more second dichroic mirrors (17; 171, 172) further is / are arranged downstream of the fifth LED light source (22) and is / are reflective for the first red LED light (23) or are transparent for the first red LED light (23).

4. A light generating system according to claim 3 and further comprising a fifth optical element (24) arranged downstream of the fifth LED light source (22) and configured to collimate the first red LED light (23).

5. A light generating system according to any one of the above claims, and further comprising: a sixth LED light source (25) configured to, in operation, emit fifth blue LED light (26), wherein the second phosphor element (15) is arranged downstream of the sixth LED light source (25), and wherein the second phosphor element is further configured to, at least partly, convert the fifth blue LED light (26) into second green converted light (27), wherein the one or more second dichroic mirrors (17; 171, 172) further is / are arranged downstream of the sixth LED light source (25), and wherein the one or more second dichroic mirrors (17; 171, 172) further is / are transparent for the fifth blue light (26) and reflective for the second green converted light (27), or wherein the one or more second dichroic mirrors (17; 171, 172) further is / are reflective for the fifth blue light (26) and transparent for the second green converted light (27), wherein the first dichroic mirror (10) and the one or more second dichroic mirrors (17; 171, 172) are configured to, in combination, combine the first red converted light (6), the second red converted light (9), the third blue LED light (12), the first green converted light (16), the second green converted light (27), and where provided the first red LED light (23), to form the system light (2).

6. A light generating system according to claim 5 when dependent on any one of claims 2-4, wherein the following applies: the LED light generating system further comprises a sixth optical element (28) arranged downstream of the sixth LED light source (25) and configured to collimate the fifth blue LED light (26), and the fourth optical element (21) is further configured to collimate the second green converted light (27).

7. A light generating system according to any one of the above claims, and further comprising: a seventh LED light source (29) configured to, in operation, emit first violet LED light, a third phosphor element (31), the third phosphor element (31) being arranged downstream of the seventh LED light source and being configured to, at least partly, convert the first violet LED light into first blue converted light (32), and a third dichroic mirror (33) arranged downstream of the seventh LED light source (29), the third dichroic mirror (33) being reflective for the first blue converted light (32), or the third dichroic mirror (33) being transparent for the first blue converted light (32), wherein the first dichroic mirror (10) and the one or more second dichroic mirror (17; 171, 172) further are arranged downstream of the third phosphor element (31) and further are transparent for the first blue converted light (32), and wherein the first dichroic mirror (10), the one or more second dichroic mirrors (17; 171, 172), and the third dichroic mirror (33) are configured to, in combination, combine: the first red converted light (6), the second red converted light (9), the third blue LED light (12), the first green converted light (16), the first blue converted light (32), where provided the second green converted light (27), and where provided the first red LED light (23), to form the system light (2).

8. A light generating system according to claim 7, and further comprising a seventh optical element (34) arranged downstream of the third phosphor element (31) and upstream of the third dichroic mirror (33) and configured to collimate the first blue converted light (32).

9. A light generating system according to claim 7 or 8, and further comprising: an eighth LED light source (35) configured to, in operation, emit second violet LED light (36), wherein the third phosphor element (31) is arranged downstream of the eighth LED light source (35), and wherein the third phosphor element (31) further is configured to, at least partly, convert the second violet LED light (36) into second blue converted light (37), wherein the third dichroic mirror (33) further is arranged downstream of the eighth LED light source (35), and wherein the third dichroic mirror (33) further is transparent for the second violet LED light (36) and reflective for the second blue converted light (37), or wherein the third dichroic mirror (33) further is reflective for the second violet LED light (36) and transparent for the second blue converted light (37), wherein the first dichroic mirror (10), the one or more second dichroic mirrors (17; 171, 172), and the third dichroic mirror (33) are configured to, in combination, combine: the first red converted light (6), the second red converted light (9), the third blue LED light (12), the first green converted light (16), the first blue converted light (32), the second blue converted light (37), where provided the second green converted light (27), and where provided the first red LED light (23), to form the system light (2).

10. A light generating system according to claims 8 and 9, wherein the following applies: the LED light generating system further comprises an eighth optical element (38) arranged downstream of the eighth LED light source (35) and configured to collimate the second violet LED light (36), andthe seventh optical element (34) is further configured to collimate the second blue converted light (37).

11. A light generating system according to any one of the above claims 7-10, and further comprising: a ninth LED light source (39) configured to, in operation, emit third violet LED light (40), wherein the first dichroic mirror (10), the one or more second dichroic mirror (17; 171, 172) and the third dichroic mirror (33) further are arranged downstream of the ninth LED light source (39) and further are transparent for the third violet LED light (40), and wherein the first dichroic mirror (10), the one or more second dichroic mirrors (17;171, 172), and the third dichroic mirror (33) are configured to, in combination, combine: the first red converted light (6), the second red converted light (9), the third blue LED light (12), the first green converted light (16), the third violet LED light (40), where provided the second green converted light (27), where provided the first blue converted light (32), where provided the second blue converted light (37), and where provided, the first red LED light (23), to form the system light (2).

12. A light generating system according to any one of the above claims, wherein the first phosphor element (5) comprises a phosphor of the type M’xM2-2xAX6 doped with tetravalent manganese, wherein M’ comprises an alkaline earth cation, wherein 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 (F).

13. A light generating system according to any one of the above claims, wherein the second phosphor element (15) comprises a phosphor of the type AsBsOn 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.

14. A light generating system according to any one of the above claims, wherein the light generating system further comprises a controller (42) configured to individually control the first LED light source (3), the second LED light source (7), the third LED light source (11) and the fourth LED light source, and where provided the fifth LED light source (22), and where provided the sixth LED light source (25), and where provided the seventhLED light source (29), and where provided the eight LED light source (35), and where provided the ninth LED light source (39).

15. A lamp or a luminaire comprising a light generating system (1) according to any one of the above claims.

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