LED with improved efficiency and filled spectral power distribution

Abstract

The invention provides a light generating system (1000) comprising a light generating device (100), a first luminescent material (210), a second luminescent material (220) and a third luminescent material (230) wherein: (A) the light generating device (100) is configured to generate device light (101) having a peak wavelength selected from the range of 435 nm to 475 nm; wherein the light generating device (100) comprises a solid state light source; (B) the first luminescent material (210) is configured to convert a portion of the device light (101) into first luminescent material light (211) comprising a color point having a u'value selected from the range of 0.08-0.17 and a v 'value selected from the range of 0.5-0.57; (C) the second luminescent material (220) is configured to convert a portion of the device light (101) into second luminescent material light (221) comprising a color point having a u'value selected from the range of 0.32-0.4 and a v 'value selected from the range of 0.52-0.58; (D) a third luminescent material (230) configured to convert a portion of the device light (101) into third luminescent material light (231); wherein the third luminescent material has a centroid wavelength ([lambda] 3c) selected from the range of 620 nm to 650 nm and a full width half maximum of 60 nm or less; (E) a light generating system (1000) configured to generate system light (1001) having a (system light) spectral power distribution, the system light comprising the device light (101), the first luminescent material light (211), the second luminescent material light (221), and the third luminescent material light (231); wherein the (system light) spectral power distribution has a first spectral power (E1p) at a first peak maximum ([lambda] 1p) of the first device light (101) and a second spectral power (Em) at a minimum between the first peak maximum ([lambda] 1p) of the first device light (101) and a second peak maximum ([lambda] 2p) of the first luminescent material light (211); and (F) the light generating device (100) and the luminescent material (210, 220, 230,...) are selected such that 1.0 < = E1p / Em < = 6.0.

Description

Technical Field

[0001] The invention relates to a light generating system and a lighting device comprising such a light generating system. Background Art

[0002] Full-spectrum white light emitting devices are known in the art. For example, WO2021 / 007123 describes a full-spectrum white light emitting device, the device comprising: a broadband solid-state excitation source for generating broadband excitation light having a dominant wavelength of about 420 nm to about 480 nm and a FWHM intensity of at least 25 nm; and a narrow-band red photoluminescent material having an emission peak wavelength of about 620 nm to about 640 nm and a FWHM intensity of less than about 30 nm; wherein the device has an efficacy of at least 130 lm / W and generates white light having a CRI Ra of 90, and wherein within a wavelength range of about 430 nm to about 520 nm, the maximum percentage intensity deviation of the above white light from the light intensity of the black body curve or CIE standard illuminant D is less than about 50%.

[0003] US2016 / 372638A discloses a semiconductor light emitting device, the device includes an LED and an associated acceptor luminescent medium, the acceptor luminescent medium includes corresponding first to fourth luminescent materials, the first to fourth luminescent materials down-convert corresponding first to fourth portions of radiation emitted by the LED into radiation having corresponding first to fourth peak wavelengths. The first peak wavelength is in the green range, and the second to fourth peak wavelengths are in the red range. The second luminescent material and the third luminescent material each emit light having a full width half-height bandwidth of at least 70 nanometers, and the fourth luminescent material emits light having a full width half-height bandwidth of less than 60 nanometers. Summary of the invention

[0004] In the art, many white light emitting lighting devices have been proposed. In view of aspects such as energy efficiency, reliability, color quality, etc., it seems that there is still a need for new white light emitting lighting devices. Therefore, one aspect of the present invention is to provide an alternative light generating system (or lighting device), which preferably further at least partially eliminates one or more of the above-mentioned disadvantages. The object of the present invention may be to overcome or alleviate at least one of the disadvantages of the prior art, or to provide a useful alternative.

[0005] According to a first aspect, the present invention provides a light generating system ("system"). In particular, the light generating system may include a light generating device ("first light generating device") and one or more luminescent materials, more particularly a first luminescent material, a second luminescent material and a third luminescent material. In an embodiment, the light generating device may be particularly configured to generate device light, in particular device light having a peak wavelength selected from the range of 435nm-475nm. In an embodiment, the light generating device comprises a solid-state light source. Furthermore, in an embodiment, the first luminescent material may be configured to convert a portion of the device light into a first luminescent material light, in particular a first luminescent material light having a color point including a u' value selected from the range of 0.08-0.17 and a v' value selected from the range of 0.5-0.57. Furthermore, in an embodiment, the second luminescent material may be configured to convert a portion of the device light into a second luminescent material light, in particular a second luminescent material light having a color point including a u' value selected from the range of 0.32-0.4 and a v' value selected from the range of 0.52-0.58. Furthermore, in an embodiment, the third luminescent material may be configured to convert a portion of the device light into a third luminescent material light, in particular wherein the third luminescent material may have a centroid wavelength (λ3c) selected from the range of 620nm-650nm, and in a specific embodiment has a full width at half maximum of 60nm or less. In a specific embodiment, the light generating system may be configured to generate a system light having a (system light) spectral power distribution, the system light comprising the device light, the first luminescent material light, the second luminescent material light and the third luminescent material light. Furthermore, in another specific embodiment, the (system light) spectral power distribution may have a first spectral power (E ) at a first peak maximum (λ1p) of the first device light. 1p ), and having a second spectral power (E ) at a minimum between a first peak maximum (λ1p) of the first device light and a second peak maximum (λ2p) of the first luminescent material light m ). Furthermore, in an embodiment, the light generating device and the luminescent material may be selected such that 1.0≤E 1p / E m ≤6.0, more particularly 1.0≤E 1p / E m ≤4.0, such as 1.0≤E 1p / E m≤2.5. Therefore, in a specific embodiment, the present invention provides a light generating system, the light generating system comprising a light generating device, a first luminescent material, a second luminescent material and a third luminescent material, wherein: (A) the light generating device is configured to generate device light having a peak wavelength selected from the range of 435nm-475nm; wherein the light generating device comprises a solid state light source; (B) the first luminescent material is configured to convert a portion of the device light into a first luminescent material light having a color point having a u' value selected from the range of 0.08-0.17 and a v' value selected from the range of 0.5-0.57; (C) the second luminescent material is configured to convert a portion of the device light into a first luminescent material light having a color point having a u' value selected from the range of 0.32-0. (D) the third luminescent material is configured to convert a portion of the device light into a third luminescent material light; wherein the third luminescent material has a centroid wavelength (λ3c) selected from the range of 620nm-650nm and a full width half maximum of 60nm or less; (E) the light generating system is configured to generate a system light having a (system light) spectral power distribution, the system light comprising the device light, the first luminescent material light, the second luminescent material light and the third luminescent material light; wherein the (system light) spectral power distribution has a first spectral power (E) at a first peak maximum (λ1p) of the first device light. 1p ) and having a second spectral power (E ) at a minimum between a first peak maximum (λ1p) of the first device light and a second peak maximum (λ2p) of the first luminescent material light m ); and (F) the light generating device and the luminescent material are selected such that 1.0≤E 1p / E m ≤6.0, more particularly 1.0≤E 1p / E m ≤4.0, such as 1.0≤E 1p / E m ≤2.5, more particularly 1.5≤E 1p / E m ≤2.5. Preferably, the system light is white light.

[0006] With such a light generating system, white light having a relatively high CRI can be generated. In addition, a relatively continuous spectral power distribution with a relatively small "cyan gap" can be provided. A relatively small or substantially no cyan gap may produce a more "filled" spectrum, which may be perceived as more natural daylight and may produce some enhanced circadian (melanin) stimulation compared to conventional white light. In addition, the relatively flat intensity in the blue-cyan spectral range may provide benefits in terms of photobiological safety and / or reduced eye fatigue compared to conventional white LED light with a significant blue peak. Moreover, such a light generating system can provide white light relatively efficiently.

[0007] As mentioned above, the light generating system may include a light generating device, a first luminescent material, a second luminescent material and a third luminescent material. These will be discussed further below.

[0008] The light generating device may be particularly configured to generate device light. In particular, the light generating device may include a light source. The light source may be particularly configured to generate light source light. In embodiments, the device light may consist essentially of device light. In other embodiments, the device light may consist essentially of converted light source light. In other embodiments, the device light may include (unconverted) light source light and converted light source light. The light source light may be converted into luminescent material light with a luminescent material and / or into up-converted light with an up-converter (see also below). The term "light generating device" may also refer to a plurality of light generating devices that can provide device light with substantially the same spectral power distribution. In specific embodiments, the term "light generating device" may also refer to a plurality of light generating devices that can provide device light with different spectral power distributions.

[0009] The term "light source" may in principle relate to any light source known in the art. It may be a conventional (tungsten) bulb, a low-pressure mercury lamp, a high-pressure mercury lamp, a fluorescent lamp, an LED (light emitting diode). In a specific embodiment, the light source comprises a solid-state LED light source (such as an LED or a laser diode (or "diode laser")). The term "light source" may also relate to a plurality of light sources, such as 2-2000 (solid-state) LED light sources. Therefore, the term LED may also refer to a plurality of LEDs. In addition, in an embodiment, the term "light source" may also refer to a so-called chip-on-board (COB) light source. The term "COB" refers in particular to an LED chip in the form of a semiconductor chip, which is neither packaged nor connected but mounted directly on a substrate such as a PCB. Therefore, a plurality of light-emitting semiconductor light sources may be configured on the same substrate. In an embodiment, a COB is a plurality of LED chips that are configured together as a single lighting module.

[0010] The term "light source" may also refer to a chip scale package (CSP). A CSP may include a single solid-state die on which a layer including a luminescent material is disposed. The term "light source" may also refer to a mid-power package. A mid-power package may include one or more solid-state dies. (Multiple) dies may be covered by a layer including a luminescent material. The die size may be equal to or less than 2 mm, such as in the range of 0.2 mm-2 mm. Therefore, in an embodiment, the light source comprises a solid-state light source. In addition, in a specific embodiment, the light source comprises a chip-scale packaged LED. Here, the term "light source" may also particularly refer to a small solid-state light source, such as having a mini size or a micro size. For example, the light source may include one or more of a mini LED and a micro LED. In particular, in an embodiment, the light source comprises a micro LED or "microLED" or "μLED". Here, the term mini size or mini LED particularly refers to a solid-state light source having a size selected from the range of 100 μm-1 mm (such as a die size, particularly a length and a width). Here, the term μ size or micro LED particularly refers to a solid-state light source having a size selected from the range of 100 μm and less (such as a die size, particularly a length and a width).

[0011] A light source may have a light escape surface. For a conventional light source such as a light bulb or a fluorescent lamp, it may be the outer surface of a glass or quartz envelope. For example, for an LED, it may be the LED die, or when a resin is applied to the LED die, it may be the outer surface of the resin. In principle, it may also be the terminal end of an optical fiber. The term escape surface particularly relates to that part of the light source, i.e. where the light actually leaves or escapes. The light source is configured to provide a light beam. The light beam (therefore) escapes from the light exit surface of the light source.

[0012] Likewise, the light generating device may comprise a light escaping surface, such as an end window. Furthermore, also, the light generating system may comprise a light escaping surface, such as an end window.

[0013] The term "light source" may refer to a semiconductor light emitting device, such as a light emitting diode (LED), a resonant cavity light emitting diode (RCLED), a vertical cavity laser diode (VCSEL), an edge emitting laser, etc. The term "light source" may also refer to an organic light emitting diode (OLED), such as a passive matrix (PMOLED) or an active matrix (AMOLED). In a particular embodiment, the light source comprises a solid-state light source (such as an LED or a laser diode). In one embodiment, the light source comprises an LED (light emitting diode). The term "light source" or "solid-state light source" may also refer to a superluminescent diode (SLED).

[0014] The term LED may also refer to a plurality of LEDs.

[0015] The term "light source" may also relate to a plurality of (substantially identical (or different)) light sources, such as 2-2000 solid-state light sources. In an embodiment, the light source may comprise one or more micro-optical elements (micro-lens arrays) downstream of a single solid-state light source (such as an LED) or downstream of a plurality of solid-state light sources (i.e., shared by a plurality of LEDs). In an embodiment, the light source may comprise an LED with on-chip optics. In an embodiment, the light source comprises a pixelated single LED (with or without optics) (on-chip beam control is provided in an embodiment).

[0016] In an embodiment, the light source may be configured to provide a primary radiation that is used such as, for example, a blue light source, such as a blue LED, or a green light source, such as a green LED, and a red light source, such as a red LED. Such LEDs that may not include a luminescent material (phosphor) may be indicated as direct color LEDs.

[0017] However, in other embodiments, the light source may be configured to provide primary radiation, and a portion of the primary radiation is converted into secondary radiation. The secondary radiation may be based on the conversion of the luminescent material. Therefore, the secondary radiation may also be indicated as luminescent material radiation. In an embodiment, the luminescent material may consist of a light source, such as an LED having a luminescent material layer or a dome including luminescent material. Such an LED may be indicated as a phosphor conversion LED or a PC LED (phosphor conversion LED). In other embodiments, the luminescent material may be configured at a distance ("remote") from the light source, such as an LED having a luminescent material layer that is not in physical contact with the die of the LED. Therefore, in a specific embodiment, the light source may be a light source that emits at least light of a wavelength selected from the range of 380nm-470nm during operation. However, other wavelengths are also possible. This light may be partially used by the luminescent material.

[0018] In an embodiment, the light generating device may include a luminescent material. In an embodiment, the light generating device may include a PCLED. In other embodiments, the light generating device may include a direct LED (i.e., without a phosphor). In an embodiment, the light generating device may include a laser device, such as a laser diode. In an embodiment, the light generating device may include a super luminescent diode. Thus, in a particular embodiment, the light source may be selected from the group of a laser diode and a super luminescent diode. In other embodiments, the light source may include an LED.

[0019] The light source may in particular be configured to generate a source light having an optical axis (O) (beam shape) and a spectral power distribution. In embodiments, the source light may comprise one or more bands, the bandwidth of which is known for lasers.

[0020] The term "light source" may (thus) refer to such a light generating element, for example a solid-state light source, or for example to a package of a light generating element, such as a solid-state power supply, and one or more luminescent materials, including elements and (other) optical devices, such as lenses, collimators. A light converting element ("converter element" or "converter") may comprise a luminescent material comprising elements. For example, a solid-state light source such as a blue LED is a light source. A combination of a solid-state light source (as a "light generating element") and a light converting element optically coupled to the solid-state light source (such as a blue LED and a light converter element) may also be a light source (but may also be indicated as a light generating device). Thus, a white LED is a light source (but may also be indicated as a (white) light generating device, for example).

[0021] The term "light source" herein may also refer to light sources including solid state light sources, such as LEDs or laser diodes or super luminescent diodes.

[0022] In an embodiment, the term "light source" may (therefore) also refer to a light source based on light conversion, such as a light source combined with a luminescence conversion material. Thus, the term "light source" may also refer to a combination of an LED and a luminescent material configured to convert at least a portion of the LED radiation, or a combination of a (diode) laser and a luminescent material configured to convert at least a portion of the (diode) laser radiation.

[0023] In an embodiment, the term "light source" may also refer to a combination of a light source (such as an LED) and a filter, which may change the spectral power distribution of the light generated by the light source. In particular, the term "light generating device" may be used to describe a light source and other (optical elements), such as filters and / or beam shaping elements, etc.

[0024] In an embodiment, the expression "different light sources" or "multiple different light sources" and similar expressions may refer to multiple solid-state light sources selected from at least two different bins. Similarly, in an embodiment, the expression "same light source" or "multiple same light sources" and similar expressions may refer to multiple solid-state light sources selected from the same bin.

[0025] The terms "solid-state light source" or "solid-state material light source" and similar terms may particularly refer to semiconductor light sources, such as light emitting diodes (LEDs), diode lasers or superluminescent diodes. In an embodiment, the light generating device comprises a solid-state light source, such as an LED. Thus, in an embodiment, the light generating device may comprise a light emitting diode (LED). In a specific embodiment, the light generating device may comprise a plurality of LEDs (see also below). Thus, in an embodiment, the system may comprise a plurality of light generating devices (which in a specific embodiment may all provide device light having substantially the same spectral power distribution).

[0026] As described above, the light generating device is configured to generate device light, in particular device light having a peak wavelength selected from the range of 435nm-475nm. With such a wavelength, some useful luminescent materials can be excited and light can also be generated, which can be used as a blue component in the spectral power distribution of the system light. In another specific embodiment, the device light has a peak wavelength selected from the range of 445nm-465nm.

[0027] As mentioned above, the light generating system may comprise one or more luminescent materials, in particular at least three different luminescent materials. These may be arranged downstream of the (first) light generating device(s).

[0028] The term "luminescent material" refers in particular to a material which can convert one or more of a first radiation, in particular UV radiation and blue radiation, into a second radiation. Typically, the first radiation and the second radiation have different spectral power distributions. Therefore, instead of the term "luminescent material", the term "luminescent converter" or "converter" may also be applied. Typically, the second radiation has a spectral power distribution at a larger wavelength than the first radiation, which is the case of so-called down-conversion. However, in a particular embodiment, the second radiation has a spectral power distribution which has an intensity at a smaller wavelength than the first radiation, which is the case of so-called up-conversion.

[0029] In an embodiment, a "luminescent material" may in particular refer to a material that is capable of converting radiation, for example, into visible light and / or infrared light. For example, in an embodiment, the luminescent material may be capable of converting one or more of UV radiation and blue radiation into visible light. In a particular embodiment, the luminescent material may also convert radiation into infrared radiation (IR). Thus, upon excitation with radiation, the luminescent material emits radiation. Typically, the luminescent material will be a downconverter, i.e. radiation of a smaller wavelength is converted into radiation with a larger wavelength (λ ex <λ em ), although in certain embodiments the luminescent material may comprise an upconverter luminescent material, ie radiation of a larger wavelength is converted into radiation having a smaller wavelength (λ ex >λ em ).

[0030] In an embodiment, the term "luminescence" may refer to phosphorescence. In an embodiment, the term "luminescence" may also refer to fluorescence. Instead of the term "luminescence", the term "emission" may also be applied. Thus, the terms "first radiation" and "second radiation" may refer to excitation radiation and emission (radiation), respectively. Likewise, in an embodiment, the term "luminescent material" may refer to phosphorescence and / or fluorescence.

[0031] The term "luminescent material" may also refer to a variety of different luminescent materials. Examples of possible luminescent materials are given below. Therefore, in certain embodiments, the term "luminescent material" may also refer to a luminescent material composition. Instead of the term "luminescent material", the term "phosphor" may also be used. These terms are known to those skilled in the art.

[0032] In an embodiment, the luminescent material is selected from garnets and nitrides, which are in particular doped with trivalent cerium or divalent europium, respectively. The term "nitride" may also refer to nitrogen oxides or nitrogen silicates, etc. Alternatively or additionally, the luminescent material(s) may be selected from silicates, in particular silicates doped with divalent europium.

[0033] In a specific embodiment, the luminescent material includes A3B5O 12 : Ce type luminescent material. Wherein in an embodiment, A comprises one or more of Y, La, Gd, Tb and Lu, in particular (at least) one or more of Y, Gd, Tb and Lu, and wherein in an embodiment, B comprises one or more of Al, Ga, In and Sc. In particular, A may comprise one or more of Y, Gd and Lu, such as in particular one or more of Y and Lu. In an embodiment, the molar ratio of yttrium and lutetium may be Y / Lu≤0.5, such as Y / Lu≤0.3. In an embodiment, Y may even be substantially absent.

[0034] In an embodiment, in particular, B may include one or more of Al and Ga, more particularly at least Al, such as substantially completely Al. In other embodiments, B may include one or more of Al and Ga, more particularly at least Ga. The previous embodiment may show an emission that is red-shifted relative to the emission of the latter embodiment; or, the latter embodiment shows an emission that may be relatively blue-shifted relative to the previous embodiment. In particular, here, blue-shifted garnet-type luminescent materials may be of interest because they may allow for relatively shallow cyan gaps. Therefore, in an embodiment, the molar ratio of aluminum to gallium may be Al / Ga≤0.5, such as Al / Ga≤0.3. In an embodiment, Al may even be substantially absent.

[0035] Therefore, particularly suitable luminescent materials are cerium-containing garnet materials. Examples of garnets include in particular A3B5O 12Garnet, wherein A comprises at least yttrium or lutetium, wherein B comprises at least aluminum. Such garnet may be doped with cerium (Ce), praseodymium (Pr) or a combination of cerium and praseodymium; however, in particular Ce. In particular, B may comprise aluminum (Al); however, in addition to aluminum, B may also partially comprise gallium (Ga) and / or scandium (Sc) and / or indium (In), in particular up to about 20% of B, more in particular up to about 10% of B (i.e., the B ions consist essentially of 90 mol % or more of Al and 10 mol % or less of one or more of Ga, Sc and In); B may in particular comprise up to about 10% of gallium. In another variant, B and O may be at least partially replaced by Si and N. The element A may in particular be selected from the group consisting of yttrium (Y), gadolinium (Gd), terbium (Tb) and lutetium (Lu). Furthermore, the content of Gd and / or Tb is particularly only about 20% of A. In a specific embodiment, the garnet luminescent material comprises (Y 1-x Lu x )3B5O 12 :Ce, wherein x is greater than or equal to 0 and less than or equal to 1. The term ":Ce" means that part of the metal ions in the luminescent material (i.e., part of the "A" ions in the garnet) are replaced by Ce. 1-x Lu x )3Al5O 12 In the case of Ce, part of Y and / or Lu is replaced by Ce. This is known to those skilled in the art. Ce will usually replace A by no more than 10%; usually, the Ce concentration will be in the range of 0.1% to 4%, in particular 0.1% to 2% (relative to A). Assuming 1% cerium and 10% yttrium, the completely correct chemical formula may be (Y 0.1 Lu 0.89 Ce 0.01 )3Al5O 12 The Ce in the garnet is substantially or exclusively in the trivalent state, as known to those skilled in the art.

[0036] In an embodiment, the luminescent material (therefore) comprises A3B5O 12 , wherein in a specific embodiment, up to 10% of the BO can be replaced by Si-N.

[0037] In certain embodiments, the luminescent material includes (Y x1 A' x2 Ce x3 )3(Al y1 B' y2 )5O 12, where x1 + x2 + x3 = 1, where x3 > 0, where 0 < x2 + x3 ≤ 0.2, where y1 + y2 = 1, where 0 ≤ y2 ≤ 0.2, and where A' includes one or more elements selected from the group consisting of lanthanide elements, and where B' includes one or more elements selected from the group consisting of Ga, In, and Sc. In an embodiment, x3 is selected from the range of 0.001 - 0.1. In the present invention, in particular, x1 > 0, such as > 0.2, such as at least 0.8. The garnet with Y can provide a suitable spectral power distribution.

[0038] In a particular embodiment, up to 10% of B-O can be replaced by Si-N. Where B in B-O refers to one or more of Al, Ga, In, and Sc (O refers to oxygen); in a particular embodiment, B-O can refer to Al-O. As described above, in a particular embodiment, x3 can be selected from the range of 0.001 to 0.04. In particular, such a luminescent material can have a suitable spectral distribution (see below), have a relatively high efficiency, have a relatively high thermal stability, and allow a high CRI (optionally in combination with the light of other light sources described herein). Thus, in a particular embodiment, A can be selected from the group consisting of Lu and Gd. Alternatively or additionally, B can include Ga. Thus, in an embodiment, the luminescent material includes (Y x1 (Lu,Gd) x2 Ce x3 )3(Al y1 Ga y2 )5O 12 , where Lu and / or Gd can be obtainable. More specifically, x3 is selected from the range of 0.001 - 0.1, where 0 < x2 + x3 ≤ 0.1, and where 0 ≤ y2 ≤ 0.1. Further, in a particular embodiment, up to 1% of B-O can be replaced by Si-N. Here, the percentage refers to the number of moles (as known in the art); see, for example, EP3149108. In a further particular embodiment, the luminescent material includes (Y x1 Ce x3 )3Al5O 12 , where x1 + x3 = 1, and where 0 < x3 ≤ 0.2, such as 0.001 - 0.1. In a particular embodiment, A can particularly include at least Y, and B can particularly include at least Al. However, in other particular embodiments, A can particularly include at least one or more of Gd and Lu, and B can particularly include at least Ga. In an embodiment, the molar ratio of yttrium, lutetium, and gadolinium can be Y / (Lu + Gd) ≤ 0.5, such as Y / (Lu + Gd) ≤ 0.3. In an embodiment, Y can even be substantially absent.

[0039] Alternatively or additionally, the luminescent material may include A3Si6N 11 :Ce 3+ A type of luminescent material, wherein A includes one or more of Y, La, Gd, Tb and Lu, such as one or more of La and Y in an embodiment.

[0040] In an embodiment, the luminescent material may alternatively or additionally include MS:Eu 2+ and / or M2Si5N8:Eu 2+ and / or MAlSiN3:Eu 2+ and / or Ca2AlSi3O2N5:Eu 2+ One or more of the following, wherein M includes one or more of Ba, Sr and Ca, and in particular, in an embodiment, includes at least Sr. Therefore, in an embodiment, the luminescent material may include one or more materials selected from the group consisting of (Ba,Sr,Ca)S:Eu, (Ba,Sr,Ca)AlSiN3:Eu and (Ba,Sr,Ca)2Si5N8:Eu. In these compounds, europium (Eu) is substantially or only divalent and replaces one or more of the indicated divalent cations. Typically, the content of Eu will not exceed 10% of the cations; its presence will be particularly in the range of about 0.5% to 10%, more particularly in the range of about 0.5% to 5%, relative to the (multiple) cations it replaces. The term ":Eu" indicates that part of the metal ions are replaced by Eu (Eu in these examples). 2+ ) is substituted. For example, assuming that there is 2% Eu in CaAlSiN3:Eu, the correct chemical formula may be (Ca 0.98 Eu 0.02 )AlSiN3. Divalent europium will typically replace divalent cations, such as the above-mentioned divalent alkaline earth cations, in particular 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); in particular, M includes calcium or strontium, or calcium and strontium, more particularly calcium in the compound. Here, Eu is introduced and replaces at least a portion of M (i.e., one or more of Ba, Sr and Ca). In addition, the material (Ba,Sr,Ca)2Si5N8:Eu can also be indicated as M2Si5N8:Eu, wherein M is one or more elements selected from the group consisting of barium (Ba), strontium (Sr) and calcium (Ca); in particular, M includes Sr and / or Ba in the compound. In another specific embodiment, M consists of Sr and / or Ba (not considering the presence of Eu), in particular 50% to 100%, more particularly 50% to 90% Ba and 50% to 0%, in particular 50% to 10% Sr, such as Ba 1.5Sr 0.5 Si5N8:Eu (i.e., 75% Ba; 25% Sr). Here, Eu is introduced and replaces at least a portion of M, i.e., one or more of Ba, Sr and Ca. Similarly, the material (Ba,Sr,Ca)AlSiN3:Eu can also be indicated as MAlSiN3:Eu, wherein M is one or more elements selected from the group consisting of barium (Ba), strontium (Sr) and calcium (Ca); in particular, M includes calcium or strontium, or calcium and strontium, more particularly calcium in the compound. Here, Eu is introduced and replaces at least a portion of M (i.e., one or more of Ba, Sr and Ca). As known to those skilled in the art, Eu in the above-mentioned luminescent materials is substantially or only in a divalent state.

[0041] In an embodiment, the red light emitting material may include one or more materials selected from the group consisting of (Ba, Sr, Ca) S: Eu, (Ba, Sr, Ca) AlSiN3: Eu, and (Ba, Sr, Ca) 2Si5N8: Eu. In these compounds, europium (Eu) is substantially or only divalent and replaces one or more of the indicated divalent cations. Typically, the content of Eu does not exceed 10% of the cations; its presence will be particularly in the range of about 0.5% to 10%, more particularly in the range of about 0.5% to 5%, relative to the (multiple) cations it replaces. The term ": Eu" indicates that part of the metal ions are replaced by Eu (Eu in these examples). 2+ ) is substituted. For example, assuming that there is 2% Eu in CaAlSiN3:Eu, the correct chemical formula may be (Ca 0.98 Eu 0.02 )AlSiN3. The divalent europium will usually replace a divalent cation, such as the above-mentioned divalent alkaline earth cation, in particular Ca, Sr or Ba.

[0042] The material (Ba, Sr, Ca) S: Eu may 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); in particular, M includes calcium or strontium, or calcium and strontium, more particularly calcium in the compound. Here, Eu is introduced and replaces at least a portion of M (i.e., one or more of Ba, Sr and Ca).

[0043] In addition, the material (Ba, Sr, Ca) 2 Si 5 N 8 : Eu may also be indicated as M 2 Si 5 N 8 : Eu, wherein M is one or more elements selected from the group consisting of barium (Ba), strontium (Sr) and calcium (Ca); in particular, M includes Sr and / or Ba in the compound. In another specific embodiment, M consists of Sr and / or Ba (not considering the presence of Eu), in particular 50% to 100%, more particularly 50% to 90% Ba and 50% to 0%, in particular 50% to 10% Sr, such as Ba 1.5 Sr 0.5 Si5N8:Eu (ie, 75% Ba; 25% Sr) Here, Eu is introduced and replaces at least a part of M, ie, one or more of Ba, Sr and Ca.

[0044] Likewise, the material (Ba, Sr, Ca)AlSiN3:Eu may also be indicated as MAlSiN3:Eu. Wherein M is one or more elements selected from the group consisting of barium (Ba), strontium (Sr) and calcium (Ca); in particular, M includes calcium or strontium, or calcium and strontium, more particularly calcium in the compound. Here, Eu is introduced and replaces at least a portion of M (i.e., one or more of Ba, Sr and Ca).

[0045] As known to the person skilled in the art, Eu in the above indicated luminescent materials is substantially or exclusively in a divalent state.

[0046] The blue light emitting material may include YSO (Y2SiO5:Ce 3+ ) or similar compounds, or BAM (BaMgAl 10 O 17 :Eu 2+ ) or similar compounds.

[0047] The term "luminescent material" in this context particularly relates to inorganic luminescent materials.

[0048] Alternatively or additionally, other luminescent materials may also be applied. For example, quantum dots and / or organic dyes may be applied and may optionally be embedded in a transmissive matrix, such as a polymer, such as PMMA, or polysiloxane, or the like.

[0049] Quantum dots are small crystals of semiconductor materials, usually only a few nanometers in width or diameter. When excited by incident light, the color of the light emitted by the quantum dots is determined by the size and material of the crystal. Therefore, light of a specific color can be generated by adapting the size of the dots. Most of the known quantum dots that emit in the visible light range are based on cadmium selenide (CdSe), with shells such as cadmium sulfide (CdS) and zinc sulfide (ZnS). Cadmium-free quantum dots such as indium phosphide (InP), copper indium sulfide (CuInS2) and / or silver indium sulfide (AgInS2) can also be used. Quantum dots show very narrow emission bands, so they show saturated colors. In addition, by adapting the size of the quantum dots, the emission color can be easily tuned. Any type of quantum dots known in the art can be used in the present invention. However, for environmental safety and concerns, cadmium-free quantum dots or at least quantum dots with very low cadmium content are preferably used.

[0050] Instead of or in addition to quantum dots, other quantum confinement structures may also be used. In the context of the present application, the term "quantum confinement structure" is to be understood as, for example, quantum wells, quantum dots, quantum rods, tripods, tetrapods or nanowires.

[0051] Organic phosphors may also be used. Examples of suitable organic phosphor materials are organic luminescent materials based on perylene derivatives, such as those available from BASF as Examples of suitable compounds include, but are not limited to, Red F305, Orange F240, Yellow F083 and F 170.

[0052] Different luminescent materials may have different spectral power distributions of the respective luminescent material light. Alternatively or additionally, such different luminescent materials may in particular have different color points (or dominant wavelengths).

[0053] As indicated above, other luminescent materials are also possible. Thus, in a particular embodiment, the luminescent material is selected from the group of divalent europium-containing nitrides, divalent europium-containing oxynitrides, divalent europium-containing silicates, cerium-containing garnets, and quantum structures. The quantum structures may, for example, include quantum dots or quantum rods (or other quantum-type particles) (see above). The quantum structures may also include quantum wells. The quantum structures may also include photonic crystals.

[0054] In particular, the first luminescent material may comprise a luminescent material emitting in the green-yellow wavelength range, in particular substantially in the green wavelength range.In particular, the first luminescent material light of the first luminescent material may be relatively broad band in the spectral power distribution (see also below).

[0055] In an embodiment, the first luminescent material may be configured to convert a portion of the device light into a first luminescent material light having a color point having a u' value selected from the range of 0.08-0.17 and a v' value selected from the range of 0.50-0.57. More particularly, a color point having a u' value selected from the range of 0.10-0.15 and a v' value selected from the range of 0.52-0.55 may be selected.

[0056] In particular, the second luminescent material may comprise a luminescent material emitting in the yellow-red wavelength range, in particular substantially in the orange-red wavelength range. More particularly, at least a portion of the first luminescent material may be in the orange wavelength range. Furthermore, in particular, the second luminescent material light of the second luminescent material may be a relatively wide band in the spectral power distribution (see also below).

[0057] In an embodiment, the second luminescent material may be configured to convert a portion of the device light into a second luminescent material light having a color point having a u' value selected from the range of 0.32-0.40 and a v' value selected from the range of 0.52-0.58. More particularly, a color point having a u' value selected from the range of 0.33-0.38 and a v' value selected from the range of 0.54-0.56 may be selected.

[0058] In particular, the second luminescent material may comprise a luminescent material emitting in the red wavelength range, in particular having a majority of the emitted wavelengths greater than about 625 nm. Furthermore, in particular, the third luminescent material light of the third luminescent material may be a relatively narrow band in the spectral power distribution (see also below).

[0059] In an embodiment, the third luminescent material may be configured to convert a portion of the device light into a third luminescent material light. In a specific embodiment, the third luminescent material may have one or more of the following: (i) a centroid wavelength (λ3c) selected from the range of 620nm-650nm and (ii) a full width half maximum of 60nm or less. In addition, in a specific embodiment, the third luminescent material may be configured to convert a portion of the device light into a third luminescent material light having a color point having a u' value selected from the range of 0.44-0.63 and a v' value selected from the range of 048-0.55, more specifically having a u' value selected from the range of 0.46-0.61 and a v' value selected from the range of 0.50-0.53.

[0060] The term "centroid wavelength" (also called λc) is known in the art and refers to the wavelength value at which half of the light energy is at a shorter wavelength and half of the energy is at a longer wavelength; the value is expressed in nanometers (nm). It is this wavelength that divides the integral of the spectral power distribution into two equal parts, as shown in the formula λc = ∑λ*I(λ) / (∑I(λ)), where the sum is over the wavelength range of interest and I(λ) is the spectral energy density (i.e., the integral of the product of wavelength and intensity over the emission band, which is normalized to the integrated intensity). The centroid wavelength can be determined, for example, under operating conditions.

[0061] By utilizing a luminescent material having such optical properties and the optical properties of a light generating device, an ideal spectral power distribution of the system light can be provided.

[0062] In certain embodiments, the light generating system may be configured to generate system light having a spectral power distribution (or system light spectral power distribution), the system light including device light, first luminescent material light, second luminescent material light, and third luminescent material light. Such system light may have a (system light) spectral power distribution having a first spectral power (E ) at a first peak maximum (λ1p) of the first device light. 1p ) and having a second spectral power (E ) at a minimum between a first peak maximum (λ1p) of the first device light and a second peak maximum (λ2p) of the first luminescent material light m ). In particular, the minimum may be a gap in the blue-green wavelength range (such as a gap in the cyan wavelength range). According to the invention, the gap may be relatively shallow. In an embodiment, the light generating device and the luminescent material may be selected such that 1.0 ≤ E 1p / E m ≤6.0, more specifically, the light emitting device and the light emitting material may be selected so that 1.0 <E 1p / E m ≤5.0, such as 1.0 <E 1p / E m ≤4.0, as in the embodiment, 1.0≤E 1p / E m ≤3.5, such as even only up to about 2.5. In an embodiment, more particularly, 1.0≤E 1p / E m ≤2.5. In an embodiment, when the system light has a correlated color temperature of a maximum of 5000K, the light generating device and the luminescent material may be selected such that 1.0≤E 1p / E m ≤2.5, especially 1.0≤E 1p / E m ≤2.0, such as 1.0 <E 1p / E m≤2.0, and when the system light has a correlated color temperature above 5000K, the light generating device and the luminescent material may be selected such that 1.0≤E 1p / E m ≤3.0, more particularly 1.0≤E 1p / E m ≤ 2.5, such as at least about 1.2, and more particularly 1.5 ≤ E 1p / E m ≤2.5.

[0063] Here, the term "violet light" or "violet emission" and similar terms may particularly relate to light with a wavelength in the range of about 380nm-440nm. In a specific embodiment, the violet light may have a centroid wavelength in the range of 380nm-440nm. The term "blue light" or "blue emission" and similar terms may particularly relate to light with a wavelength in the range of about 440nm-490nm (including some purple and cyan hues). In a specific embodiment, the blue light may have a centroid wavelength in the range of 440nm-490nm. The term "green light" or "green emission" and similar terms may particularly relate to light with a wavelength in the range of about 490nm-560nm. In a specific embodiment, the green light may have a centroid wavelength in the range of 490nm-560nm. The term "yellow light" or "yellow emission" and similar terms may particularly relate to light with a wavelength in the range of about 560nm-590nm. In a specific embodiment, the yellow light may have a centroid wavelength in the range of 560nm-590nm. The terms "orange light" or "orange emission" and similar terms may particularly relate to light having a wavelength in the range of about 590nm-620nm. In a particular embodiment, the orange light may have a centroid wavelength in the range of 590nm-620nm. The terms "red light" or "red emission" and similar terms may particularly relate to light having a wavelength in the range of about 620nm-750nm. In a particular embodiment, the red light may have a centroid wavelength in the range of 620nm-750nm. The terms "cyan light" or "cyan emission" and similar terms particularly relate to light having a wavelength in the range of about 490nm-520nm. In a particular embodiment, the cyan light may have a centroid wavelength in the range of 490nm-520nm. The terms "amber light" or "amber emission" and similar terms may particularly relate to light having a wavelength in the range of about 585nm-605nm, such as about 590nm-600nm. In a particular embodiment, the amber light may have a centroid wavelength in the range of 585nm-605nm. The expression "light having one or more wavelengths in the wavelength range" and similar expressions may specifically indicate that the indicated light (or radiation) has a spectral power distribution having at least an intensity at the one or more wavelengths in the indicated wavelength range. For example, a solid-state light source emitting blue light will have a spectral power distribution having an intensity at one or more wavelengths in the wavelength range of 440nm-495nm.

[0064] The term "visible", "visible light" or "visible emission" and similar terms refer to light having one or more wavelengths in the range of about 380nm-780nm. Here, UV may particularly refer to a wavelength selected from the range of 190nm-380nm, such as 200nm-380nm.

[0065] Some embodiments of the light-emitting materials are described below starting with the third light-emitting material.

[0066] In particular, the third luminescent material may be a relatively narrowband emitter. Using (multiple) such luminescent materials, the efficiency may be relatively high and the CRI may also be high. Broadband emitters in the (far) red may be less efficient. In an embodiment, the third luminescent material may include one or more emission bands having a full width at half maximum (FWHM) of a maximum of 70 nm, more particularly a maximum of 60 nm, such as a maximum of 50 nm. In a specific embodiment, the third luminescent material may include one or more emission lines having a full width at half maximum of about 30 nm, more particularly a maximum of 20 nm.

[0067] In a specific embodiment, the third luminescent material includes M' doped with tetravalent manganese. x M 2-2x A light-emitting material of type AX6, wherein M' comprises an alkaline earth cation, M comprises an alkaline cation, x is in the range of 0-1, wherein A comprises a tetravalent cation, including one or more of silicon and titanium, and wherein X comprises a monovalent anion, including at least fluorine.

[0068] M' doped with tetravalent manganese x M 2-2x AX6 type luminescent materials are described in WO2013121355A1, which is incorporated herein by reference. Paragraphs of WO2013121355A1 are also reproduced here.

[0069] Here, M' doped with tetravalent manganese x M 2-2x AX6 may also be referred to as a "phosphor", that is, in one embodiment, the phrase "comprising M' doped with tetravalent manganese" x M 2-2x The phosphor of AX6 can also be understood as M' doped with tetravalent manganese phosphorus x M 2-2x AX6 phosphor, or (quaternary) manganese-doped M' x M 2-2x AX6 phosphor, or simply "phosphor".

[0070] The relevant basic cations (M) are sodium (Na), potassium (K) and rubidium (Rb). Optionally, lithium and / or cesium can also be applied. In a preferred embodiment, M includes at least potassium. In another embodiment, M includes at least rubidium. The phrase "wherein M includes at least potassium" means, for example, that in molar M' x M 2-2xOf all the M cations in AX6, a portion comprises K+, and optionally the remainder comprises one or more other monovalent (basic) cations (see also below). In another preferred embodiment, M comprises at least potassium and rubidium. Optionally, M' x M 2-2x AX6 luminescent material has a hexagonal phase. In another embodiment, M' x M 2-2x The AX6 luminescent material has a cubic phase.

[0071] Relevant alkaline earth metal cations (M') are magnesium (Mg), strontium (Sr), calcium (Ca) and barium (Ba), especially one or more of Sr and Ba.

[0072] In one embodiment, a combination of different alkaline cations may be used. In another embodiment, a combination of different alkaline earth metal cations may be used. In another embodiment, a combination of one or more alkaline cations and one or more alkaline earth metal cations may be used. For example, KRb may be used. 0.5 Sr 0.25 AX6. As mentioned above, x may be in the range of 0-1, in particular x<1. In one embodiment, x=0.

[0073] The term "tetravalent manganese" refers to Mn 4+ This is a well-known luminescent ion. In the above chemical formula, part of the tetravalent cation A (such as Si) is replaced by manganese. Therefore, M' doped with tetravalent manganese x M 2-2x AX6 can also be expressed as M' x M 2- 2x A 1-m Mn m X6. The molar percentage of manganese (ie the percentage by which it replaces the tetravalent cation A) is generally in the range of 0.1%-15%, especially 1%-12%, ie m is in the range of 0.001-0.15, especially in the range of 0.01-0.12.

[0074] A comprises a tetravalent cation, preferably at least silicon. A may optionally (further) comprise one or more of titanium (Ti), germanium (Ge), tin (Sn) and zinc (Zn). Preferably at least 80%, even more preferably at least 90%, such as at least 95%, of M consists of silicon. Thus, in a particular embodiment, M' x M 2-2x AX6 can also be described as M' x M 2-2x A 1-m-t-g-s- zr Mn m Ti tGe g Sn s Zr zr X6, wherein m and x are as described above, wherein t, g, s, zr are each individually preferably in the range of 0-0.2, in particular 0-0.1, even more particularly 0-0.05, wherein t+g+s+zr is less than 1, in particular equal to or less than 0.2, preferably in the range of 0-0.2, in particular 0-0.1, even more particularly 0-0.05, wherein A is in particular Si. X is preferably fluorine (F).

[0075] As mentioned above, M refers to a monovalent cation, but preferably includes at least potassium and / or rubidium. Other monovalent cations that M may also include may be selected from lithium (Li), sodium (Na), cesium (Cs) and ammonium (NH4 + ). In one embodiment, preferably at least 80% (i.e. 80% of all moles of form M), even more preferably at least 90%, such as 95%, of M consists of potassium and / or rubidium. In particular, in these embodiments, x is therefore zero.

[0076] Therefore, in a particular embodiment, M' x M 2-2x AX6 can also be described as (K 1-r-l-n-c-nh R r Li l Na n Cs c (NH4) nh )2AX6, wherein r is in the range of 0-1, wherein l, n, c, nh are each individually preferably in the range of 0-1, preferably 0-0.2, particularly 0-0.1, even more particularly 0-0.05, and wherein r+l+n+c+nh is in the range of 0-1, particularly l+n+c+nh is less than 1, particularly equal to or less than 0.2, preferably in the range of 0-0.2, particularly 0-0.1, even more particularly 0-0.05. X is preferably fluorine (F).

[0077] As mentioned above, one or more alkaline earth cations may also be present instead of or in addition to the alkaline cation(s). x M 2-2x AX6 can also be described as Mg mg Ca ca Sr sr Ba ba (K k R r Li l Na n Cs c (NH4) nh)2AX6, wherein k, r, l, n, c, nh are each individually in the range of 0-1, wherein mg, ca, sr, ba are each individually in the range of 0-1, and wherein mg+ca+sr+ba+k+r+l+n+c+nh=1. In an embodiment, k=1, and the others (mg, ca, sr, ba, r, l, n, c, nh) are 0.

[0078] As mentioned above, X refers to monovalent anions, but at least includes fluorine. Other monovalent anions that may be present optionally may be selected from the group consisting of chlorine (Cl), bromine (Br) and iodine (I). Preferably, at least 80%, even more preferably at least 90%, such as 95%, of X consists of fluorine. Thus, in a particular embodiment, M' x M 2-2x AX6 can also be described as M' x M 2-2x A(F 1-cl-b-i Cl cl Br b I i )6, wherein cl, b, i are each individually preferably in the range of 0-0.2, in particular 0-0.1, even more particularly 0-0.05, and wherein cl+b+i is less than 1, in particular equal to or less than 0.2, preferably in the range of 0-0.02, in particular 0-0.1, even more particularly 0-0.05. In particular, X consists essentially of F (fluorine).

[0079] Therefore, M' x M 2-2x AX6 can also be described as (K 1-r-l-n-c-nh R r Li l Na n Cs c (NH4) nh )2Si 1-m-t-g-s- zr Mn m Ti t Ge g Sn s Zr zr (F 1-cl-b-i Cl cl B b I i )6, wherein the values ​​of r, l, n, c, NH, m, t, g, s, zr, cl, b, i are as described above. X is preferably fluorine (F).

[0080] More specifically, M' x M 2-2x AX6 can also be described as Mg mg Caca Sr sr Ba ba (K k R r Li l Na n Cs c (NH4) nh )2Si 1-m-t-g-s-zr Mn m Ti t Ge g Sn s Zr zr (F 1-cl-b-i Cl cl Br b I i )6, wherein k, r, l, n, c, nh are each individually in the range of 0-1, wherein mg, ca, sr, ba are each individually in the range of 0-1, wherein mg+ca+sr+ba+k+r+l+n+c+nh=1, and the values ​​of m, t, g, s, zr, cl, b, i are as described above. X is preferably fluorine (F).

[0081] In a preferred embodiment, M' x M 2-2x AX6 comprises K2SiF6 (also indicated herein as KSiF system). As indicated above, in another preferred embodiment, M' x M 2-2x AX6 includes KRbSiF6 (i.e., r=0.5, and l, n, c, nh, t, g, s, zr, cl, b, i are 0) (also indicated here as K, Rb system). As mentioned above, part of silicon is replaced by manganese (i.e., the chemical formula can also be described as K2Si 1-m Mn m F6 or KRbSi 1-m Mn m F6, where m is as shown above, or described as KRbSiF6:Mn and K2SiF6:Mn, respectively). Since manganese replaces part of the host lattice ions and has a specific function, it is also indicated as a "dopant" or "activator". Therefore, hexafluorosilicates are treated with manganese (Mn 4+ ) doping or activation.

[0082] The luminescent material may also be coated, as described in WO2013121355A1.

[0083] In an embodiment, the third light emitting material may include (K, Rb)2SiF6:Mn 4+ Alternatively or additionally, in an embodiment, the third luminescent material may include K2SiF6:Mn 4+Alternatively or additionally, in an embodiment, the third luminescent material may include K2TiF6:Mn 4+ In an embodiment, the third luminescent material may include K2(Si,Ti)F6:Mn 4+ As described above, “Si, Ti” may indicate one or more of Si and Ti.

[0084] Such a third luminescent material may provide third luminescent material light having an emission line (in the red wavelength range) having a full width at half maximum of about 20 nm when excited by the device light.

[0085] Instead of or in addition to M' doped with tetravalent manganese x M 2-2x AX6 type luminescent materials may also use luminescent materials based on quantum structures. Therefore, in an embodiment, the third luminescent material includes a luminescent material based on a quantum structure, for example, wherein the third luminescent material includes quantum dots. Here, the term "luminescent material based on a quantum structure" may also be indicated as a "quantum structure" or a "quantum confinement structure". Examples of quantum structures are also given above: In the context of the present application, the term "quantum confinement structure" should be understood as, for example, quantum wells, quantum dots, quantum rods, tripods, quadrupeds or nanowires, etc. Quantum structures may also include photonic crystals. Luminescent materials based on quantum structures may include, for example, semiconductor materials.

[0086] Examples of quantum structure-based luminescent materials (such as semiconductor nanocrystal (core) shell materials) include, but are not limited to: red (e.g., (CdSe) ZnS (core) shell), green (e.g., (CdZnSe) CdZnS (core) shell, etc.), and blue (e.g., (CdS) CdZnS (core) shell (see also above for examples of specific semiconductor-based wavelength converter nanoparticles). Here, the terms "semiconductor nanocrystal" and "QD" are used interchangeably. Another term for quantum dots is luminescent nanocrystals. Therefore, the outer surface described above can be a bare quantum dot (i.e., not including other The wavelength converter nanoparticles may be selected from the group consisting of core-shell nanoparticles, wherein the core and the shell include one or more of the following: CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, Hg STe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, Cd HgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe, GaN, GaP, GaAs, AlN, AlP, AlAs, InN, InP, InAs, GaNP, GaNAs, GaPAs, AlNP , AlNAs, AlPAs, InNPs, InNAs, InPAs, GaAlNPs, GaAlNAs, GaAlPAs, GaInNPs, GaInNAs, GaInPAs, InAlNPs, InAlNAs, and InAlPAs. Typically, the core and shell comprise the same class of materials, but are essentially composed of different materials, such as a ZnS shell surrounding a CdSe core. In one embodiment, the quantum dot comprises a core / shell luminescent nanocrystal comprising CdSe / ZnS, InP / ZnS, InP / ZnSe, InP / ZnSe 1-x S x , PbSe / PbS, CdSe / CdS, CdTe / CdS or CdTe / ZnS.

[0087] In a particular embodiment, the available amount of the third luminescent material, relative to the total weight of the luminescent material, is such that in the total spectral power distribution of visible light (i.e., 380nm-780nm), up to a maximum of about 25% of the spectral power is provided by the third luminescent material light. For example, in an embodiment, the available amount of the third luminescent material can be such that in the total spectral power distribution of visible light, a minimum of about 1% of the spectral power is provided by the third luminescent material light.

[0088] In an embodiment, the quantum structure based luminescent material may provide 0.01 wt%-15 wt%, such as in particular 2 wt%-8 wt% of the luminescent material. Alternatively, in an embodiment, about 5 wt%-60 wt% of the luminescent material may be provided by a manganese based luminescent material. However, other values ​​are also possible.

[0089] In the following, some embodiments of the first luminescent material and the second luminescent material are described with reference to some of the above-mentioned luminescent materials.

[0090] In an embodiment, both the first luminescent material light and the second luminescent material light may have a full width at half maximum of at least 60 nm, such as more particularly at least 70 nm, in the spectral power distribution of the system light. For example, the FWHM of the first luminescent material light and / or the FWHM of the second luminescent material light may be particularly at least 80 nm. Of course, the FWHM may be different, because the first luminescent material and the second luminescent material may be different luminescent materials.

[0091] In a specific embodiment, the first luminescent material is a garnet type doped with cerium. In an embodiment, the first luminescent material may include A3B5O 12 : Ce type luminescent material, 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 (see also above). In particular, in an embodiment, A comprises Lu and / or B comprises Ga. In this way, the emission can be blue-shifted, for example relative to Y3Al5O 12 :Ce 3+ .

[0092] In a particular embodiment, the second luminescent material is of nitride type, doped with divalent europium. In an embodiment, the second luminescent material may comprise a luminescent material of the MAlSiN3:Eu type, wherein M is one or more elements selected from the group consisting of Ba, Sr and Ca (see also above). In particular, in an embodiment, M may comprise Sr. However, M may also comprise Ca. In a particular embodiment. M may comprise Ca and Sr. This may provide a luminescent material with desired (optical) properties.

[0093] The luminescent material may be arranged downstream of the light generating device. In particular, the luminescent material may be arranged downstream of a plurality of light generating devices.

[0094] The terms "upstream" and "downstream" relate to the arrangement of items or features relative to the propagation of light from a light generating component (here particularly a light source), wherein, relative to a first position within a light beam from the light generating component, a second position in the light beam closer to the light generating component is "upstream" and a third position within the light beam further away from the light generating component is "downstream".

[0095] The luminescent material may be configured remote from the one or more light generating devices.In other embodiments, at least a portion of the luminescent material may be configured in (physical) contact with the one or more light generating devices.

[0096] The luminescent material may be provided as a single layer comprising all luminescent materials, or may be provided as a multilayer coating, wherein one or more layers comprise luminescent materials of different compositions. The luminescent material may be provided as a coating on one or more light generating devices. The luminescent material may be embedded in another material, such as a polymer material, which may be provided as a bulk or (coating) layer.

[0097] The luminescent material can be configured in a reflection mode or a transmission mode. In the transmission mode, it can be relatively easy to mix the light source light in the luminescent material light, which can help generate the required spectral power distribution. In the reflection mode, thermal management can be easier because most of the luminescent material can be in thermal contact with a thermally conductive element (such as a heat sink or a radiator). In the reflection mode, in an embodiment, a portion of the light source light can be reflected by the luminescent material and / or the reflector and can be mixed in the luminescent material light. The reflector can be configured downstream of the luminescent material (in the reflection mode). In particular, here, the luminescent material is configured in the transmission mode.

[0098] In an embodiment, the light generating system may include a plurality of light generating devices and a light emitting layer configured downstream of the plurality of light generating devices, wherein the light emitting layer includes a first light emitting material, a second light emitting material, and a third light emitting material.

[0099] In particular, in an embodiment, the light generating system may include a chip-on-board light generating device, wherein the chip-on-board light generating device includes a plurality of light generating devices and a light emitting layer configured downstream of the plurality of light generating devices. In particular, the light emitting layer may include a first light emitting material, a second light emitting material, and a third light emitting material. Alternatively, the light generating system may include a dome-shaped body configured downstream of the light generating device. The dome-shaped body may include a first light emitting material, a second light emitting material, and a third light emitting material. Furthermore, alternatively, the light generating system may include a reflective cup in which the light emitting material is configured. The light generating device may be at least partially configured in the reflective cup. The light emitting material may be provided as such, or may consist of a light transmissive body in the reflective cup, such as dispersed in a resin (e.g., silicone). Furthermore, alternatively, the light generating system may include an LED filament.

[0100] In an embodiment, the LED filament may include an elongated substrate. In an embodiment, the elongated substrate may be light-transmissive (for LED light, see below). The substrate may have a first major surface on a first side of the substrate and a second major surface on a second side of the substrate opposite the first side. A plurality of LEDs may be mounted on the first major surface and configured to emit LED light. The sealant may cover the plurality of LEDs (on the first major surface) and at least a portion of the first major surface, and optionally also cover at least a portion of the second major surface. Optionally, a plurality of LEDs may also be mounted on the second major surface and configured to emit LED light. The sealant may also cover the plurality of LEDs (on the second major surface) (and at least a portion of the second major surface). The sealant may include a luminescent material. The luminescent material may be configured to convert at least a portion of the LED light. The sealant may also transmit at least a portion of the (unconverted) LED light. The sealant may include a resin, such as a silicone, in which the luminescent material is embedded.

[0101] For example, using a relatively blue-shifted garnet phosphor with a relatively short-wavelength broadband red phosphor and a narrow-band red luminescent material (such as a luminescent material based on a quantum structure, such as quantum dots or Mn-based 4+ Phosphors) can provide at least 2.5% efficiency gain over existing systems.

[0102] The system may include other optical devices, and the optical devices may, for example, be configured downstream of the luminescent material. The term "optical device" may particularly refer to (one or more) optical elements. Therefore, the terms "optical device" and "optical element" may refer to the same item. The optical device may include one or more mirrors, reflectors, collimators, lenses, prisms, diffusers, phase plates, polarizers, diffraction elements, gratings, dichroics, arrays of one or more of the above items, etc. Alternatively or additionally, the term "optical device" may refer to a holographic element or a mixing rod. In an embodiment, the optical device may include one or more of a beam expander optical device and a zoom lens optical device. Please refer to the above for examples of optical devices. In an embodiment, the optical device may include an integrator, such as a "Koehler integrator" (or "Koehler integrator").

[0103] In an embodiment, the light generating system may be configured to generate white system light.

[0104] The term "white light" and similar terms herein are known to a person skilled in the art. It particularly relates to light having a correlated color temperature (CCT) between about 1800K and 20000K, such as between 2000K and 20000K, in particular between 2700K-20000K, for general lighting, in particular in the range of about 2000K-7000K, such as in the range of about 2700K to 6500K. In an embodiment, for example, for backlighting purposes, or for other purposes, the correlated color temperature (CCT) may in particular be in the range of about 7000K to 20000K. Furthermore, in an embodiment, the correlated color temperature (CCT) is in particular within about 15 SDCM (standard deviation of color matching) from the BBL (black body locus), in particular within about 10 SDCM from the BBL, even more in particular within about 5 SDCM from the BBL. In a particular embodiment, the correlated color temperature (CCT) may be selected from the range of 6000K-12000K, such as from the range of 7000K-12000K, such as at least 8000 K. Furthermore, in an embodiment, the correlated color temperature (CCT) may be selected from the range of 6000K-12000K, such as from the range of 7000K-12000K, in combination with a CRI of at least 70.

[0105] The light generating device and the luminescent material are selected such that the color rendering index of the system light is selected from the range of at least 85, more particularly at least 90, and the correlated color temperature is selected from the range of 2000K-8000K, such as from the range of 2000K-6500K.

[0106] As described above, the light generating system may include one or more light generating devices. One or more light generating devices are controllable, such as the radiant flux is controllable and / or the spectral power distribution of the device light is controllable. In addition, optionally, the light generating system may include one or more second light generating devices configured to generate a second device light. In the operating mode, the system light may include such a second device light. However, in other embodiments, the light generating system includes only a light generating device, which is configured to generate device light, at least a portion of which is used by the luminescent material to be converted into luminescent material light (i.e., a first light generating device). However, the system may also include two or more different types of first light generating devices, such as first light generating devices from different intervals. In this way, the blue component in the system light can be controllable.

[0107] In certain embodiments, the system may include two or more arrangements of each one or more light generating devices and a first luminescent material, a second luminescent material, and a third luminescent material, as described herein. One or more of such arrangements may be configured to generate primary light having a first correlated color temperature CCT1, and one or more other arrangements may be configured to generate secondary light having a second correlated color temperature CCT2, wherein CCT1 may be different from CCT2 (e.g., at least 500K, see also below). Thus, the primary light and the secondary light may have different spectral power distributions (and therefore may also have different correlated color temperatures). This may be achieved, for example, when different arrangements of luminescent materials (selected from the first luminescent material, the second luminescent material, and the third luminescent material) are combined differently. In certain embodiments, the system light may include one or more of the primary light and the secondary light. In this way, the control system may (also) control the system light by controlling the light generating devices of the two or more arrangements.

[0108] Therefore, the system may further comprise a control system configured to control the system light, such as its radiant flux and / or its spectral power distribution. In particular, this may be achieved by controlling one or more light generating devices (and optionally (multiple) second light generating devices).

[0109] The term "control" and similar terms particularly refer to at least determining the behavior of an element or supervising its operation. Therefore, herein, "control" and similar terms may refer to applying behavior (determining the behavior or supervising the operation of an element) to an element, such as, for example, measuring, displaying, actuating, opening, moving, changing temperature, etc. In addition, the term "control" and similar terms may also include monitoring. Therefore, the term "control" and similar terms may include applying behavior to an element, and also include imposing behavior and monitoring elements on an element. The control of an element may be performed by a control system, which may also be indicated as a "controller". Therefore, the control system and the element may be functionally coupled at least temporarily or permanently. The element may include a control system. In an embodiment, the control system and the element may not be physically coupled. Control may be performed via wired and / or wireless control. The term "control system" may also refer to a plurality of different control systems, which are particularly functionally coupled, wherein, for example, one control system may be a master control system, and one or more other control systems may be slave control systems. The control system may include or may be functionally coupled to a user interface.

[0110] The control system may also be configured to receive and execute instructions from a remote control. In an embodiment, the control system may be controlled via an App on a device, such as a portable device, such as a smartphone or I-phone, a tablet, etc. Thus, the device is not necessarily coupled to the lighting system, but may be (temporarily) functionally coupled to the lighting system.

[0111] Thus, in an embodiment, the control system may (also) be configured to be controlled by an App on a remote device. In such an embodiment, the control system of the lighting system may be a control from the control system or in slave mode. For example, the lighting system may be identifiable with a code, in particular a unique code of the respective lighting system. The control system of the lighting system may be configured to be controlled by an external control system, which may access the lighting system based on the knowledge of the (unique) code (input by a user interface with an optical sensor (e.g. a QR code reader)). The lighting system may also include components for communicating with other systems or devices, such as based on Bluetooth, Thread, WIFI, LiFi, ZigBee, BLE or WiMAX or another wireless technology.

[0112] The system, device or equipment may perform actions in a "mode" or "operating mode" or "operable mode". The term "operable mode" may also be indicated as a "control mode". Similarly, in a method, an action or phase or step may be performed in a "mode" or "operating mode" or "operable mode". This does not exclude that the system, device or equipment may also be adapted to provide another control mode or multiple other control modes. Similarly, this may not exclude that one or more other modes may be executed before and / or after executing the mode.

[0113] However, in an embodiment, a control system may be provided, which is adapted to provide at least a control mode. If other modes are available, the selection of such a mode may in particular be performed via a user interface, although other options (such as executing a mode according to a sensor signal or a (time) scheme) are also possible. In an embodiment, an operating mode may also refer to a system, device or apparatus that can only be operated in a single operating mode (i.e. "on", without further adjustability).

[0114] Therefore, in an embodiment, the control system may be controlled according to one or more of an input signal of a user interface, a sensor signal (of a sensor) and a timer.The term "timer" may refer to a clock and / or a predetermined time scheme.

[0115] Thus, by means of such a system, light with a controllable spectral power distribution may be provided. Furthermore, by means of such a system, light with a controllable correlated color temperature and / or a controllable color rendering index may be provided. Furthermore, by means of such a system, a spectral power distribution which is partially or substantially conformal to the spectral power distribution (in visible light) of a blackbody radiator (emission) may be provided. The fact that the light generating system may be configured to generate (white) system light does not exclude embodiments of the system, wherein the system may also be operated in other operating modes. In particular, in embodiments, the spectral power distribution of the system light may be controllable. Thus, in embodiments of a first operating mode (of the light generating system), the light generating system may be configured to generate white system light, and in a second operating mode (of the light generating system), the light generating system may be configured to generate non-white system light.

[0116] Therefore, in an embodiment, the light generating system may further comprise a control system configured to control the spectral power distribution of the system light. In particular, the control system may be configured to control the correlated color temperature of the system light to a value selected from the range of 1800K-12000K, such as selected from the range of 1800K-6500K, but other values ​​are not excluded herein (see also above).

[0117] In a particular embodiment, the correlated color temperature of the system light may be controllable within a CCT control range of at least 500K in the range of 1800K-12000K, such as selected from the range of 1800K-6500K, such as controllable within a CCT control range of at least 1000K. For example, the CCT of the system light may be controllable between 2700K-4000K (i.e., within a CCT control range of 1300K) or within a range of 2000K-4500K (i.e., within a CCT control range of 2500K). Thus, in an embodiment, the CCT (of the white system light) may be controlled from a first value CCT1 to a second value CCT2, wherein |CCT2-CCT1|≥500K, more particularly |CCT2-CCT1|≥1000K.

[0118] The term "white light" in this context is known to the person skilled in the art. It particularly relates to light having a correlated color temperature (CCT) between about 2000K and 20000K, in particular 2700K-20000K, for general lighting in particular in the range of about 2700K to 6500K, and for backlighting purposes in particular in the range of about 7000K to 20000K, in particular within about 15SDCM (standard deviation of color matching) from the BBL (black body locus), in particular within about 10SDCM from the BBL, even more particularly within about 5SDCM from the BBB.

[0119] In an embodiment, the system may include a light exit port, such as an end window or (other) optical element, or an opening, from which system light can escape to the outside of the system. The system may include a housing including such a light exit port. The housing may at least partially enclose one or more light generating devices and luminescent material, and optionally one or more optical elements.

[0120] The light generating system may be part of or may be applied to an office lighting system, a home application system, a shop lighting system, a household lighting system, an accent lighting system, a spotlight system, a theatre lighting system, a fibre optic application system, a projection system, a self-luminous display system, a pixelated display system, a segmented display system, a warning sign system, a medical lighting application system, a signage system, a decorative lighting system, a portable system, an automotive application, a (outdoor) road lighting system, a city lighting system, a greenhouse lighting system, a horticultural lighting, digital projection or an LCD backlight. For example, the light generating system (or lamp) may be part of or may be applied to an optical communication system or a disinfection system.

[0121] In yet another aspect, the present invention also provides a lamp or lamp comprising a light generating system as defined herein. The lamp may also include a housing, an optical element, a shutter, etc. The lamp or lamp may also include a housing surrounding the light generating system. The lamp or lamp may include a light window in the housing, or a housing opening, through which the system light can escape from the housing. In yet another aspect, the present invention also provides a projection device comprising a light generating system as defined herein. In particular, a projection device or "projector" or "image projector" may be an optical device that projects an image (or moving image) onto a surface, such as a projection screen. The projection device may include one or more light generating systems, such as described herein. Therefore, in one aspect, the present invention also provides a light generating device comprising a light generating system as defined herein, the light generating device being selected from a group consisting of a lamp, a lamp, a projection device, a disinfection device, a photochemical reactor, and an optical wireless communication device. The light generating device may include a housing or carrier configured to accommodate or support one or more elements of the light generating system (see also above). For example, in an embodiment, the light generating device may include a housing or carrier configured to accommodate or support one or more of the light generating device and the luminescent material. BRIEF DESCRIPTION OF THE DRAWINGS

[0122] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which corresponding reference characters indicate corresponding parts, and in which:

[0123] Figures 1a-1c schematically depict some embodiments;

[0124] Figures 2a-2b show some possible spectral power distributions;

[0125] Figures 2c-2d show some additional aspects; and

[0126] Figure 3 Some applications are depicted schematically. The schematic diagrams are not necessarily drawn to scale. DETAILED DESCRIPTION

[0127] 1a-1c, the present invention provides a light generating system 1000 in an embodiment, which includes a light generating device 100, a first luminescent material 210, a second luminescent material 220, and a third luminescent material 230. The light generating device 100 may be configured to generate a device light 101 having a peak wavelength selected from the range of 435nm-475nm. The light generating device 100 may include a solid-state light source. In an embodiment, the light generating device 100 may include a light emitting diode. Reference numeral 1020 refers to a support member, such as a PCB.

[0128] The first luminescent material 210 may be configured to convert a portion of the device light 101 into a first luminescent material light 211 including a color point having a u' value selected from the range of 0.08-0.17 and a v' value selected from the range of 0.5-0.57. The second luminescent material 220 may be configured to convert a portion of the device light 101 into a second luminescent material light 221 including a color point having a u' value selected from the range of 0.32-0.4 and a v' value selected from the range of 0.52-0.58. The third luminescent material 230 may be configured to convert a portion of the device light 101 into a third luminescent material light 231. The third luminescent material has a centroid wavelength (λ3c) selected from the range of 620nm-650nm and a full width half maximum of 60nm or less (see also Figures 2a-2b).

[0129] The light generating system 1000 may be configured to generate system light 1001 having a (system light) spectral power distribution, the system light including the device light 101 , the first luminescent material light 211 , the second luminescent material light 221 , and the third luminescent material light 231 .

[0130] 1a, the light generating system 1000 may include a chip-on-board light generating device 1110. The chip-on-board light generating device 1110 may include a plurality of light generating devices 100 and a light emitting layer 1200 configured downstream of the plurality of light generating devices 100. In particular, the light emitting layer 1200 may include a first light emitting material 210, a second light emitting material 220, and a third light emitting material 230.

[0131] For example, referring to Fig. 1b, the light generating system 1000 may include a dome-shaped body 1210 configured downstream of the light generating device 100. The dome-shaped body 1210 may include a first luminescent material 210, a second luminescent material 220, and a third luminescent material 230. In alternative embodiments, the luminescent materials 210, 220, 230 may be formed as a layer between the light generating device 100 and at least a portion of the dome-shaped body 1210. In such embodiments, the dome-shaped body 1210 may not include luminescent materials.

[0132] Fig. 1c schematically depicts a light generating system 1000 comprising a reflective cup 1030, wherein luminescent materials 210, 220, 230 are comprised in the reflective cup 1030. The luminescent materials 210, 220, 230 may be provided as such, but may also be encapsulated in a supporting material such as a (silicone) resin.

[0133] In an alternative embodiment not depicted, the light generating system 1000 may include a filament.

[0134] Referring also to FIG. 2a (and effectively to FIG. 2b ), the (system light) spectral power distribution has a first spectral power (E ) at a first peak maximum (λ1p) of the first device light 101. 1p ) and has a second spectral power (E ) at the minimum between the first peak maximum (λ1p) of the first device light 101 and the second peak maximum (λ2p) of the first luminescent material light 211 m ). In particular, the light generating device 100 and the luminescent materials 210, 220, 230, ... may be selected such that 1.0≤E 1p / E m ≤6.0, such as 1.0≤E 1p / E m ≤5.0, more particularly 1.0≤E 1p / E m ≤2.5. In an embodiment, the light generating device 100 and the luminescent materials 210, 220, 230 are selected such that when the system light 1001 has a correlated color temperature of a maximum of 5000K, 1.0≤E 1p / E m ≤2.0, and is selected so that when the system light 1001 has a correlated color temperature higher than 5000K, 1.0≤E 1p / E m ≤2.5, more particularly 1.5≤E 1p / E m ≤2.5.

[0135] In certain embodiments, the third luminescent material 230 may be configured to convert a portion of the device light 101 to third luminescent material light 231 including a color point having a u' value selected from the range of 0.46-0.61 and a v' value selected from the range of 0.50-0.53.

[0136] In certain embodiments, the third light emitting material 230 may include M′ doped with tetravalent manganese. x M 2-2x For AX6 type luminescent materials, M' may include alkaline earth cations, M may include alkaline cations, x may be in the range of 0-1, A may include tetravalent cations including one or more of silicon and titanium, and X may include monovalent anions including at least fluorine.

[0137] The term "luminescent material" or the indication "210, 220, 230, ..." in an embodiment may particularly refer to a combination of a first luminescent material, a second luminescent material, a third luminescent material and optionally other luminescent materials. In a specific embodiment, all luminescent materials included in the system are selected from the first luminescent material, the second luminescent material and the third luminescent material.

[0138] In an embodiment, the third light emitting material 230 may include (K, Rb)2SiF6:Mn 4+ and / or K2SiF6:Mn 4+ and / or K2TiF6:Mn 4+ Alternatively or additionally, in an embodiment, the third luminescent material 230 may include a luminescent material based on a quantum structure. For example, the third luminescent material 230 may include quantum dots.

[0139] Referring to Figures 2a-2b, the CRI of all spectral power distributions is at least 80 (or even at least about 90). In Figure 2b, reference numeral 231a refers to the emission of the Mn-based luminescent material and reference numeral 231b refers to the emission of the quantum structure-based luminescent material. Referring to Figures 2a-2b, the first luminescent material light 211 and the second luminescent material light 221 may have a full width at half maximum of at least 70 nm in the spectral power distribution of the system light 1001. Both figures show masked spectral power distributions on the same light generating device and luminescent materials 210, 220, 230, ranging from 2700K to 6500K. In addition, Figure 2b also shows an embodiment in which the third luminescent material includes a quantum structure-based luminescent material.

[0140] In an embodiment, the first luminescent material 210 may include A3B5O 12 : Ce type luminescent material, A may include one or more of Y, La, Gd, Tb and Lu, and B may include one or more of Al, Ga, In and Sc. In particular, A may include Lu and / or B may include Ga.

[0141] In a specific embodiment, the second luminescent material 220 may include a luminescent material of the MAlSiN3:Eu type, and M may be one or more elements selected from the group consisting of Ba, Sr, and Ca. In particular, M may include Sr. However, M may also include Ca. In a specific embodiment, M may include Ca and Sr.

[0142] In an embodiment, the device light 101 may have a peak wavelength selected from the range of 445 nm-465 nm.

[0143] In certain embodiments, the light generating device 100 and the luminescent material may be selected such that the system light 1001 has a color rendering index selected from a range of at least 90 and a correlated color temperature selected from a range of 2000K-8000K.

[0144] To find the optimal solution, simulations were carried out using a wide range of yellow / green phosphors 210 (see Fig. 2c, which gives the phosphor CIE u', v' color points) in combination with a wide range of red phosphors 220 (see Fig. 2d, which gives the phosphor CIE u', v' color points) and Mn-based or QD-based luminescent materials 230 (in different amounts). The modeling was based on measured and simulated absorption and emission spectra and took into account the interaction of the phosphors. The target color points for the optimization were selected on the BBL as 2700, 3000, 3500, 4000, 5000, and 6500 K. The final efficiency at 3500 K (as an example) was determined (CE = conversion efficiency, Lm / W opt ). One possible solution is to use a yellow / green garnet phosphor (Fig. 2c) selected from 0.14 < u' < 0.24 and 0.55 < v' < 0.57, and its maximum efficiency is 260 Lm / Wopt .

[0145] However, surprisingly, even more efficient solutions were found. A more efficient solution uses, for example, a blue-shifted garnet phosphor (Fig. 2c) with 0.10 < u' < 0.15 and 0.52 < v' < 0.55 in combination with a red phosphor (Fig. 2d) with, for example, 0.34 < u' < 0.38 and 0.54 < v' < 0.56.

[0146] Fig. 2c shows an overview of the yellow / green phosphor color points. Box V shows the color points of the first luminescent material described herein, etc. Fig. 2d shows an overview of the wide red phosphor color points. Box II shows the color points of the second luminescent material described herein, etc.

[0147] The solutions proposed herein can provide an efficiency gain between 2.5% and 7.5% relative to existing solutions, while maintaining a high CRI and providing a reduced cyan gap.

[0148] The indication of luminescent materials 210, 220, 230 does not exclude that other luminescent materials may be available. The indication "luminescent materials 210, 220, 230..." and similar indications may indicate luminescent materials 210, 220, 230 and optionally one or more other luminescent materials.

[0149] Figure 3 An embodiment of a luminaire 2 including a light generation system 1000 as described above is schematically depicted. Reference numeral 301 indicates a user interface, which may be functionally coupled to a control system 300 that is included in or functionally coupled to the light generation system 1000. Figure 3Also schematically depicted is an embodiment of a lamp 1 comprising a light generating system 1000. Reference numeral 3 denotes a projection device or a projection system which may be used for projecting an image, such as at a wall, which projection device or projection system may also comprise the light generating system 1000. Thus, Figure 3 An embodiment of a lighting device 1200 comprising the light generating system 1000 described herein is schematically depicted, the lighting device being selected from the group of a lamp 1, a luminaire 2, a projection device 3, a disinfection device, a photochemical reactor, and an optical wireless communication device. In an embodiment, such a lighting device may be a lamp 1, a luminaire 2, a projection device 3, a disinfection device, or an optical wireless communication device. Lighting device light escaping from the lighting device 1200 is indicated by reference numeral 1201. The lighting device light 1201 may essentially consist of the system light 1001, and may therefore in a particular embodiment be the system light 1001. Reference numeral 1300 refers to a space, such as a room.

[0150] The term "plurality" means two or more.

[0151] Those skilled in the art will understand the terms "substantially" or "substantially" and similar terms herein. The terms "substantially" or "substantially" may also include embodiments with "complete", "completely" or "all", etc. Therefore, in an embodiment, the adjective "substantially" or "substantially" may also be deleted. Where applicable, the term "substantially" or the term "substantially" may also relate to 90% or higher, such as 95% or higher, particularly 99% or higher, even more particularly 99.5% or higher (including 100%).

[0152] The term "comprising" also includes embodiments wherein the term "comprising" means "consisting of.

[0153] The term "and / or" specifically relates to one or more items mentioned before and after "and / or". For example, the expression "item 1 and / or item 2" and similar expressions may relate to one or more of item 1 and item 2. In one embodiment, the term "comprising" may refer to "consisting of", but in another embodiment, may also refer to "comprising at least the defined species and optionally one or more other species".

[0154] In addition, the terms first, second, third, etc. in the specification and claims are used to distinguish similar elements and not necessarily to describe a sequential or chronological order. It should be understood that the terms so used are interchangeable under appropriate circumstances, and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein.

[0155] Devices, apparatuses or systems etc. may be described herein during operation. It will be clear to those skilled in the art that the present invention is not limited to methods of operation or devices, apparatuses or systems in operation.

[0156] It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims.

[0157] In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

[0158] The use of the verb "comprise" and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. Unless the context clearly requires otherwise, throughout the specification and claims, the words "comprises", "comprising", etc. should be interpreted as being inclusive and not exclusive or exhaustive; that is, in the sense of "including but not limited to".

[0159] The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

[0160] The invention may be implemented by means of hardware comprising several distinct elements and by means of a suitably programmed computer. In a device claim, an apparatus claim or a system claim enumerating several means, several of these means may be implemented by the same hardware. The fact that certain measures are cited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. In another aspect, the invention (therefore) provides a software product which, when run on a computer, is capable of implementing (one or more embodiments of) the method described herein.

[0161] The present invention also provides a control system that can control a device, apparatus or system, or can perform a method or process described herein. In addition, the present invention also provides a computer program product that, when run on a computer functionally coupled to or composed of a device, apparatus or system, controls one or more controllable elements of such a device, apparatus or system.

[0162] The present invention is also applicable to a device, apparatus or system comprising one or more features described in the specification and / or shown in the drawings. The present invention also relates to a method or process comprising one or more features described in the specification and / or shown in the drawings.

[0163] The various aspects discussed in this patent can be combined to provide additional advantages. In addition, those skilled in the art will appreciate that the embodiments can be combined, and more than two embodiments can also be combined. In addition, some features can form the basis of one or more partition applications.

Claims

1. A light generating system (1000), comprising a light generating device (100), a first luminescent material (210), a second luminescent material (220) and a third luminescent material (230), wherein: - the light generating device (100) is configured to generate device light (101) having a peak wavelength selected from the range of 435nm-475nm; wherein the light generating device (100) comprises a solid state light source; - the first luminescent material (210) is configured to convert a portion of the device light (101) into first luminescent material light (211), the first luminescent material light having a color point having a u' value selected from the range of 0.08-0.17 and a v' value selected from the range of 0.50-0.57; - the second luminescent material (220) is configured to convert a portion of the device light (101) into second luminescent material light (221), the second luminescent material light having a color point having a u' value selected from the range of 0.32-0.40 and a v' value selected from the range of 0.52-0.58; - the third luminescent material (230) is configured to convert a portion of the device light (101) into third luminescent material light (231); wherein the third luminescent material has a centroid wavelength (λ3c) selected from the range of 620nm-650nm and a full width half maximum of 60nm or less; - the light generating system (1000) is configured to generate system light (1001) having a spectral power distribution, the system light comprising device light (101), first luminescent material light (211), second luminescent material light (221) and third luminescent material light (231); wherein the spectral power distribution has a first spectral power (E 1p ) at a first peak maximum value (λ1p) of the first device light (101). 1p ), and having a second spectral power (E ) at a minimum value between the first peak maximum value (λ1p) of the first device light (101) and the second peak maximum value (λ2p) of the first luminescent material light (211) m ); - the light generating device (100) and the luminescent material (210, 220, 230, ...) are selected such that 1.0≤E 1p / E m ≤2.5; and - the light generating device (100) and the luminescent materials (210, 220, 230, ...) are selected such that the system light (1001) has a color rendering index selected from the range of at least 85 and a correlated color temperature selected from the range of 2000K-8000K.

2. The light generating system (1000) according to claim 1, wherein the third luminescent material (230) is configured to convert a portion of the device light (101) into a third luminescent material light (231), the third luminescent material light (231) having a color point having a u' value selected from the range of 0.46-0.61 and a v' value selected from the range of 0.50-0.53, wherein the first luminescent material light (211) has a color point having a u' value selected from the range of 0.10-0.15 and a v' value selected from the range of 0.52-0.55; and wherein the second luminescent material light (221) has a color point having a u' value selected from the range of 0.33-0.38 and a v' value selected from the range of 0.54-0.

56.

3. The light generating system (1000) according to any one of the preceding claims, wherein the third luminescent material (230) comprises M' doped with tetravalent manganese. x M 2-2x A light emitting material of type AX6, 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, including one or more of silicon and titanium, and wherein X comprises a monovalent anion, including at least fluorine.

4. The light generating system (1000) according to any one of the preceding claims, wherein the third luminescent material (230) comprises K2SiF6:Mn 4+ .

5. The light generating system (1000) according to any one of the preceding claims, wherein the third luminescent material (230) comprises a quantum structure based luminescent material.

6. The light generating system (1000) according to any of the preceding claims, wherein both the first luminescent material light (211) and the second luminescent material light (221) have a full width at half maximum of at least 70 nm in the spectral power distribution of the system light (1001).

7. The light generating system (1000) according to any one of the preceding claims, wherein the first luminescent material (210) comprises A3B5O 12 :Ce 3+ A type of light-emitting material, wherein A includes one or more of Y, La, Gd, Tb and Lu, and wherein B includes one or more of Al, Ga, In and Sc.

8. The light generating system (1000) of claim 7, wherein A comprises Lu and / or wherein B comprises Ga.

9. The light generating system (1000) according to any of the preceding claims, wherein the second luminescent material (220) comprises a luminescent material of the MAlSiN3:Eu type, wherein M is one or more elements selected from the group consisting of Ba, Sr and Ca.

10. The light generating system (1000) according to claim 9, wherein M comprises Sr and Ca.

11. The light generating system (1000) according to any one of the preceding claims, wherein when the system light (1001) has a correlated color temperature of a maximum of 5000 K, the light generating device (100) and the luminescent material (210, 220, 230, ...) are selected such that 10≤E 1p / E m ≤2.0, and when the system light (1001) has a correlated color temperature higher than 5000K, the light generating device (100) and the luminescent material (210, 220, 230, ...) are selected such that 1.0≤E 1p / E m ≤2.5; wherein the device light (101) has a peak wavelength selected from the range of 445nm-465nm; and wherein the light generating device (100) comprises a light emitting diode.

12. The light generating system (1000) according to any one of the preceding claims 1 to 11 comprises a plurality of light generating devices (100) and a light emitting layer (1200), wherein the light emitting layer is arranged downstream of the plurality of light generating devices (100), wherein the light emitting layer (1200) comprises the first light emitting material (210), the second light emitting material (220) and the third light emitting material (230).

13. The light generating system (1000) according to any one of the preceding claims 1 to 11 comprises a dome-shaped body (1210), which is arranged downstream of the light generating device (100), wherein the dome-shaped body (1210) comprises the first luminescent material (210), the second luminescent material (220) and the third luminescent material (230).

14. The light generating system (1000) according to any of the preceding claims, wherein the light generating device (100) and the luminescent material (210, 220, 230, ...) are selected so that the system light (1001) has a color rendering index selected from a range of at least 90 and a correlated color temperature selected from a range of 2000K-6500K.

15. A lighting device (1200) selected from the group of a lamp (1) and a luminaire (2), the lighting device comprising the light generating system (1000) according to any one of claims 1 to 14.

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