High-intensity laser phosphor lighting with CCT control

Abstract

The present invention provides a light-generating system comprising a first light-generating device, a second light-generating device, a first luminescent material, and a control system, wherein (A) a plurality of first light-generating devices are provided with a first laser light source and configured to generate first device light having a first device light peak wavelength (λ1) and a first spectral power distribution, the first device light peak wavelength (λ1) being selected from a wavelength range of 425 to 465 nm; (B) a second light-generating device is provided with a second laser light source and configured to generate first device light having a first device light peak wavelength (λ1) and a first spectral power distribution; (C) a first luminescent material configured in a light-receiving relationship with the first light-generating device and configured to receive at least a portion of the first device light at a luminescent material emission centroid wavelength (λ ) within a green-yellow wavelength range; and (D) a second luminescent material configured to receive at least a portion of the first device light at a luminescent material emission centroid wavelength (λ ) within a green-yellow wavelength range; and c,l (D) the light-generation system is configured to generate system light 1001 including one or more of the first device light, the second device light, and the first luminescent material light, the system light having a controllable correlated color temperature; (E) a control system configured to (a) in a first mode of operation of the light-generation system, the system light has a first correlated color temperature CCT1, and CCT1 ≧4000K; (b) in a second operating mode of the light generating system, the system light has a second correlated color temperature (CCT2), where CCT2-CCT1≧1000K; (c) in at least one of the operating modes, the system light has a correlated color temperature selected from a range of at least 7000K; and (d) in both operating modes, the system light has a color rendering index of at least 70.

Description

[Technical Field]

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

[0002] Light-emitting devices including lasers are known in the art. For example, U.S. Patent Application Publication No. 2020 / 0232919 describes a method for manufacturing a light-emitting device, the method including: preparing a fluorescent material; classifying a plurality of laser elements into a short wavelength group and a long wavelength group such that the peak wavelength of light emitted from the laser elements in the short wavelength group is shorter than the excitation peak wavelength of the fluorescent material, and the peak wavelength of light emitted from the laser elements in the long wavelength group is longer than the excitation peak wavelength of the fluorescent material; and selecting one or more laser elements from each of the short wavelength group and the long wavelength group, and combining them with the fluorescent material to manufacture a light-emitting device.

[0003] WO 2021 / 063878(A1) discloses a light-generating device configured to generate device light, the light-generating device comprising: a first laser light source configured to generate a blue first source light; a second laser light source configured to generate a green second source light; a third laser light source configured to generate a red third source light; a fourth laser light source configured to generate a blue fourth source light; a first luminescent material configured to convert at least a portion of the first source light into a first green / yellow luminescent material light; optical elements configured to combine (i) the unconverted first source light, (ii) the second source light, the third source light, (iv) the fourth source light, and (v) the first luminescent material light to provide white device light; and a control system configured to control the laser light sources. Summary of the Invention [Problem to be solved by the invention]

[0004] For example, a white LED light source has a maximum output of approximately 300 lm / mm 2 while static phosphor-converted laser white light sources can provide even more, up to about 20,000 lm / mm 2 Ce-doped garnets (e.g., YAG, LuAG) may be the most suitable luminescence converters that can be used for pumping with blue laser light because the garnet matrix has extremely high chemical stability. Furthermore, at low Ce concentrations (e.g., less than 0.5%), thermal quenching can occur only above approximately 200°C. Furthermore, the emission from Ce has an extremely fast decay time, so optical saturation can essentially be avoided. For example, assuming reflection mode operation, blue laser light can be incident on the phosphor. This can, in embodiments, achieve nearly complete conversion of the blue light, resulting in the emission of converted light. For this reason, the use of garnet phosphors, which have relatively high stability and thermal conductivity, has been proposed. However, other phosphors may also be applicable. When extremely high power densities are used, thermal management can remain a challenge.

[0005] High-brightness light sources can be used in applications such as projection, stage lighting, spot lighting, and automotive lighting. For this purpose, laser-phosphor technology can be used, where a laser provides the laser light and, for example, a (remote) phosphor converts the laser light into converted light. The phosphor, in embodiments, may be placed on or inserted into a heat sink for improved thermal management and therefore higher brightness.

[0006] It would be desirable to increase the radiant flux and / or improve the efficiency of such light emitting devices. Furthermore, controllable light emitting devices are desirable. Furthermore, controllable light emitting devices with high CCT (correlated color temperature) with high radiant flux, such as for stage lighting, are desirable.

[0007] It is therefore an aspect of the present invention to provide an alternative light generating system (and / or lighting device), which preferably also at least partially obviates one or more of the above-mentioned disadvantages. The present invention may have as an object to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative.

[0008] According to a first aspect, the present invention provides a light-generation system ("system") comprising a plurality of first light-generating devices, a second light-generating device, and a first luminescent material. The light-generation system may further comprise a control system. In embodiments, the first light-generating device may comprise a first laser light source. In particular, the plurality of first light-generating devices may be configured to generate first device light having a first device light peak wavelength (λ1) and a first spectral power distribution. In certain embodiments, the first device light peak wavelength (λ1) may be selected from a wavelength range of 425 to 465 nm. Also, in embodiments, the second light-generating device may comprise a second laser light source. In particular, the second light-generating device may be configured to generate second device light having a second device light peak wavelength (λ2) and a second spectral power distribution. In particular, the second spectral power distribution may be different from the first spectral power distribution. In certain embodiments, the second device light peak wavelength (λ2) may be selected from the range of 470 to 490 nm. Further, in embodiments, the first luminescent material may be configured in a light-receiving relationship with the first light-generating device, and in particular, configured to convert at least a portion of the first device light into first luminescent material light. The first luminescent material light has a luminescent material emission centroid wavelength (λ2) in the green-yellow wavelength range. c,l). However, in particular embodiments, the first luminescent material may not be configured to be in a light-receiving relationship with the second light-generating device. In particular embodiments, the light-generating system may be configured to generate system light including one or more of the first device light, the second device light, and the first luminescent material light. In particular embodiments, the system light may have a controllable correlated color temperature. In particular embodiments, the control system may be configured to (a) control the first light-generating device and the second light-generating device in a first operating mode of the light-generating system such that the system light has a first correlated color temperature (CCT1), where CCT1≧4000K. Alternatively, or in addition, in particular embodiments, the control system may be configured to (b) control the first light-generating device and the second light-generating device in a second operating mode of the light-generating system such that the system light has a second correlated color temperature (CCT2), where CCT2−CCT1≧1000K. Alternatively, or in addition, in embodiments, the control system may be configured to (c) control the first light-generating device and the second light-generating device such that in at least one of the operational modes the system light has a correlated color temperature selected from a range of at least 7000 K. Also, alternatively, or in addition, in embodiments, the control system may be configured to (d) control the first light-generating device and the second light-generating device such that the system light in both operational modes has a color rendering index of at least 70.Therefore, in particular, the present invention provides, in an embodiment, a light-generating system comprising a first light-generating device, a second light-generating device, a first luminescent material, and a control system, wherein: (A) a plurality of first light-generating devices comprise a first laser light source and are configured to generate first device light having a first device light peak wavelength (λ1) and a first spectral power distribution, the first device light peak wavelength (λ1) being selected from a wavelength range of 425 to 465 nm; (B) a plurality of second light-generating devices comprise a first laser light source and are configured to generate first device light having a first device light peak wavelength (λ1) and a first spectral power distribution, the first device light peak wavelength (λ1) being selected from a wavelength range of 425 to 465 nm; (C) a first luminescent material configured in a light-receiving relationship with the first light-generating device, the first light-generating device including a second laser light source and configured to generate second device light having a second device light peak wavelength (λ2) and a second spectral power distribution different from the first spectral power distribution, the second device light peak wavelength (λ2) being selected from the range of 470 to 490 nm; and (D) a first luminescent material configured in a light-receiving relationship with the first light-generating device, the first light-generating device receiving at least a portion of the first device light at a luminescent material emission centroid wavelength (λ) within a green-yellow wavelength range. c,l (D) the light-generation system is configured to generate system light 1001 including one or more of the first device light, the second device light, and the first luminescent material light, the system light having a controllable correlated color temperature; and (E) a control system configured to: (a) in a first operating mode of the light-generation system, the system light has a first correlated color temperature CCT1, the CCT1≧4000K. (b) in a second operating mode of the light generating system, the system light has a second correlated color temperature (CCT2), where CCT2-CCT1≧1000K; (c) in at least one of the operating modes, the system light has a correlated color temperature selected from a range of at least 7000K; and (d) the system light in both operating modes has a color rendering index of at least 70, in particular at least 80.

[0009] Such a system may provide high-brightness light with a relatively high correlated color temperature, which may also be controllable. For example, in this manner, a relatively simple, low-cost, high-brightness laser phosphor light generation system with CCT control may be provided, e.g., for stage lighting. Furthermore, the system may allow the color point to remain relatively close to the blackbody locus while varying the CCT, particularly at relatively high correlated color temperatures. Furthermore, the system may be capable of providing system light with a color rendering index (CRI) greater than 70. In embodiments, the CRI may be at least 80, such as at least 85. In certain embodiments, the CRI may even be at least 90.

[0010] As mentioned above, the present invention provides a light-generating system comprising a first light-generating device, a second light-generating device, a first luminescent material, and an optional control system. In the following, we first describe some general aspects of light-generating devices (in general) and laser devices (in general).

[0011] The light-generating device may be particularly configured to generate device light. In particular, the light-generating device may comprise a light source. The light source may be particularly configured to generate source light. In embodiments, the device light may consist essentially of device light. In other embodiments, the device light may consist essentially of converted source light. In still other embodiments, the device light may include (unconverted) source light and converted source light. The source light may be converted to luminescent material light by a luminescent material and / or converted to upconverted light by an upconverter (see also below). The term "light-generating device" may also refer to multiple light-generating devices capable of providing device light having essentially the same spectral power distribution. In certain embodiments, the term "light-generating device" may also refer to multiple light-generating devices capable of providing device light having different spectral power distributions.

[0012] The term "light source" can in principle relate to any light source known in the art. The light source can be a conventional (tungsten) lamp, a low-pressure mercury lamp, a high-pressure mercury lamp, a fluorescent lamp, or an LED (light emissive diode). In certain embodiments, the light source includes a solid-state LED light source (such as an LED or a laser diode (or "diode laser")). The term "light source" can also relate to a plurality of light sources, such as 2 to 2000 (solid-state) LED light sources. Therefore, the term LED can also refer to a plurality of LEDs. Furthermore, the term "light source" can also refer to so-called chip-on-board (COB) light sources in embodiments. The term "COB" specifically refers to an LED chip in the form of a semiconductor chip that is mounted directly on a substrate, such as a PCB, without encapsulation or connection. Therefore, multiple light-emitting semiconductor light sources can be configured on the same substrate. In embodiments, a COB is a multi-LED chip configured together as a single lighting module.

[0013] The term "light source" may also refer to a chip scale package (CSP). A CSP may include a single solid die having a layer containing a luminescent material disposed thereon. The term "light source" may also refer to a mid-power package. A mid-power package may include one or more solid die. The die may be covered by a layer containing a luminescent material. The die dimensions may be 2 mm or less, for example, in the range of 0.2 to 2 mm. Thus, in embodiments, the light source includes a solid-state light source. Furthermore, in certain embodiments, the light source includes a chip scale package LED. As used herein, the term "light source" may also refer to compact solid-state light sources, particularly those having a mini- or micro-size. For example, the light source may include one or more of a mini LED and a micro LED. In particular, in embodiments, the light source includes a micro LED, or "micro LED," or "μ LED." As used herein, the term "mini-size LED" or "mini LED" particularly refers to a solid-state light source having dimensions, particularly length and width, such as a die size selected from the range of 100 μm to 1 mm. In this specification, the term μ-size LED or micro LED particularly denotes a solid-state light source having dimensions such as die dimensions, especially length and width, selected from the range of 100 μm or less.

[0014] A light source may have a light escape surface. With reference to conventional light sources, such as light bulbs or fluorescent lamps, the light escape surface may be the outer surface of a glass or quartz envelope. With respect to LEDs, the light escape surface may be, for example, the LED die, or the outer surface of the resin if a resin is applied to the LED die. In principle, the light escape surface may also be the end of a fiber. The term escape surface particularly relates to that part of a light source from which light actually leaves or escapes the light source. A light source is configured to provide a beam of light. This beam of light therefore escapes from the light exit surface of the light source.

[0015] Similarly, the light-generating device may have a light-escape surface, such as an end window.Furthermore, similarly, the light-generating system may have a light-escape surface, such as an end window.

[0016] 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), or an edge-emitting laser. The term "light source" may also refer to an organic light-emitting diode (OLED), such as a passive-matrix (PMOLED) or active-matrix (AMOLED). In certain embodiments, the light source comprises a solid-state light source (such as an LED or 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).

[0017] The term LED can also refer to multiple LEDs.

[0018] The term "light source" may also refer to multiple (essentially identical (or different)) light sources, such as 2 to 2000 solid-state light sources. In embodiments, the light source may include one or more micro-optical elements (an array of microlenses) downstream of a single solid-state light source, such as an LED, or downstream of multiple solid-state light sources (i.e., shared, for example, by multiple LEDs). In embodiments, the light source may include an LED with on-chip optics. In embodiments, the light source includes a pixelated single LED (with or without optics) (which, in embodiments, provides on-chip beam steering).

[0019] In embodiments, the light source may be configured to provide primary radiation for use by itself, 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, which may not include a luminescent material ("phosphor"), are sometimes referred to as direct color LEDs.

[0020] However, in other embodiments, the light source may be configured to provide primary radiation, with a portion of the primary radiation being converted to secondary radiation. The secondary radiation may be based on conversion by the luminescent material. Therefore, the secondary radiation may also be referred to as luminescent material radiation. The luminescent material may be included in the light source, such as an LED having a luminescent material layer or a dome containing the luminescent material. Such an LED may be referred to as a phosphor-converted LED or PC LED. In other embodiments, the luminescent material may be configured at some distance from the light source ("remote"), such as an LED having a luminescent material layer that is not in physical contact with the LED die. Therefore, in certain embodiments, the light source may emit light at a wavelength selected from at least the range of 380 to 470 nm during operation. However, other wavelengths are also possible. This light may be used, in part, by the luminescent material.

[0021] In embodiments, the light-generating device may include a luminescent material. In embodiments, the light-generating device may include a PC LED. In other embodiments, the light-generating device may include a direct-emitting LED (i.e., one without phosphor). In embodiments, the light-generating device may include a laser device, such as a laser diode. In embodiments, the light-generating device may include a superluminescent diode. Thus, in certain embodiments, the light source may be selected from the group of laser diodes and superluminescent diodes. In other embodiments, the light source may include an LED.

[0022] The light source may be specifically configured to generate source light having an optical axis (O), a beam shape, and a spectral power distribution. The source light may, in embodiments, have one or more bands with bandwidths as known for lasers.

[0023] The term "light source" can therefore refer to the light-generating element itself, such as a solid-state light source, or to a package of a light-generating element, such as a solid-state light source, with an element containing a luminescent material and one or more (other) optics, such as a lens or collimator. A light converter element ("converter element" or "converter") can include an element containing a luminescent material. A solid-state light source itself, 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 converter element optically coupled to the solid-state light source, such as a blue LED and a light converter element, can also be a light source (but can also be referred to as a light-generating device). A white LED is therefore a light source (but can also be referred to as a (white) light-generating device, for example).

[0024] The term "light source" as used herein may also refer to light sources including solid state light sources such as LEDs or laser diodes or superluminescent diodes.

[0025] The term "light source" may therefore also refer in embodiments to light sources based on the conversion of light, such as a light source in combination with a luminescence converter material. The term "light source" may therefore 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.

[0026] In embodiments, the term "light source" may refer to a combination of a light source, such as an LED, and an optical filter that can change the spectral power distribution of the light generated by the light source. In particular, the term "light-generating device" may be used to cover the light source and further (optical components), such as optical filters and / or beam-shaping elements.

[0027] The phrases "different light sources" or "multiple different light sources," and similar phrases, in embodiments, may refer to multiple solid-state light sources selected from at least two different bins. Similarly, the phrases "same light source" or "multiple identical light sources," and similar phrases, in embodiments, may refer to multiple solid-state light sources selected from the same bin.

[0028] The terms "solid state light source" or "solid state material light source" and similar terms may refer to semiconductor light sources, such as light emitting diodes (LEDs), diode lasers, or superluminescent diodes, among others.

[0029] The term "laser source" refers in particular to a laser. Such a laser may be configured to generate laser source light having one or more wavelengths in the UV, visible, or infrared, in particular having wavelengths selected from the spectral wavelength range of 200-2000 nm, for example 300-1500 nm. The term "laser" in particular refers to a device that emits light via a process of light amplification based on stimulated emission of electromagnetic radiation.

[0030] In particular, in embodiments, the term "laser" may refer to a solid-state laser. In certain embodiments, the term "laser" or "laser source" or similar terms refer to a laser diode (or diode laser).

[0031] Therefore, in embodiments, the light source comprises a laser light source. In embodiments, the term "laser" or "solid state laser" or "solid state material laser" refers to lasers such as cerium-doped lithium strontium (or calcium) aluminum fluoride (Ce:LiSAF, Ce:LiCAF), chromium-doped chrysoberyl (alexandrite) lasers, chromium ZnSe (Cr:ZnSe) lasers, divalent samarium-doped calcium fluoride (Sm:CaF) lasers, Er:YAG lasers, erbium-doped and erbium-ytterbium co-doped gas Laser, F-center laser, Holmium YAG (Ho:Nd:YAG) laser, Nd:YAG laser, NdCrYAG laser, Neodymium-doped yttrium calcium oxoborate Nd:YCa4O(BO3)3 or Nd:YCOB, Neodymium-doped yttrium orthovanadate (Nd:YVO4) laser, Neodymium-glass (Nd:glass) laser, Neodymium-YLF (Nd:YLF) solid-state laser, Promethium-147-doped phosphate glass (147Pm 3+ :glass) solid-state laser, ruby ​​laser (Al2O3:Cr 3+ ), thulium YAG (Tm:YAG) laser, titanium sapphire (Ti:sapphire; Al2O3:Ti 3+ ) lasers, trivalent uranium-doped calcium fluoride (U:CaF2) solid-state lasers, ytterbium-doped glass lasers (rod, plate / chip, and fiber), ytterbium YAG (Yb:YAG) lasers, Yb2O3 (glass or ceramics) lasers, etc.

[0032] For example, light sources, including second and third harmonic generation embodiments, include F-center lasers, yttrium orthovanadate (Nd:YVO4) lasers, promethium-147 doped phosphate glass (147Pm 3+ :glass), and titanium sapphire (Ti:sapphire; Al2O3:Ti 3+ ) lasers. For example, taking into account second and third harmonic generation, such a light source may be used to generate blue light.

[0033] In embodiments, the terms "laser" or "solid state laser" or "solid state material laser" may refer to one or more of semiconductor laser diodes, such as GaN, InGaN, AlGaInP, AlGaAs, InGaAsP, lead salt, vertical cavity surface emitting laser (VCSEL), quantum cascade laser, hybrid silicon laser, etc.

[0034] The laser may be combined with an upconverter to reach shorter (laser) wavelengths. For example, the upconversion may be achieved by some (trivalent) rare earth ions or by nonlinear crystals. Alternatively, the laser may be combined with a downconverter, such as a dye laser, to reach longer (laser) wavelengths.

[0035] As can be derived from below, the term "laser light source" may also refer to a plurality of (different or identical) laser light sources. In certain embodiments, the term "laser light source" may refer to a plurality N of (identical) laser light sources. In embodiments, N=2 or more. In certain embodiments, N may be at least 5, such as in particular at least 8. In this way, higher brightness may be obtained. In embodiments, the laser light sources may be arranged in a laser bank (see also above). The laser bank may, in embodiments, include a heat sink and / or optics, e.g., a lens for collimating the laser light. Thus, in embodiments, the lasers in a laser bank may share the same optics.

[0036] The laser light source is configured to generate laser source light (or "laser light"). The source light may consist essentially of laser source light. The source light may also comprise laser source light of two or more (different or the same) laser sources. For example, laser source light of two or more (different or the same) laser sources may be incoupled in a light guide to provide a single light beam comprising laser source light of two or more (different or the same) laser sources. Thus, in certain embodiments, the source light is in particular collimated source light. In yet further embodiments, the source light is in particular (collimated) laser source light.

[0037] The laser source light, in embodiments, may have one or more bands, with a bandwidth as is known for lasers. In certain embodiments, the bands may be relatively well-defined lines, such as those with a full width half maximum (FWHM) of less than 20 nm at room temperature, such as 10 nm or less. The source light therefore has a spectral power distribution (intensity on an energy scale as a function of wavelength) that may include one or more (narrow) bands.

[0038] The (source light) beam may be a focused or collimated (laser) source light beam. The term "focused" may particularly refer to converging to a small spot. This small spot may be at the individual converter region, or (slightly) upstream or (slightly) downstream of the converter region. In particular, the focusing and / or collimation may be such that the cross-sectional shape (perpendicular to the optical axis) of the beam at the individual converter region (at the side) is not substantially larger than the cross-sectional shape (perpendicular to the optical axis) of the individual converter region (where the source light illuminates the individual converter region). The focusing may be performed using one or more optical systems, such as (focusing) lenses. In particular, two lenses may be applied to focus laser source light. The collimation may be performed using one or more (other) optical systems, such as collimating elements, such as lenses and / or parabolic mirrors. In embodiments, the beam of (laser) source light may be relatively highly collimated, such as in embodiments ≦2° (FWHM), more particularly ≦1° (FWHM), and most particularly ≦0.5° (FWHM). Therefore, ≦2° (FWHM) may be considered as (highly) collimated source light. Optical systems may be used to provide the (highly) collimated light (see also above).

[0039] The term "solid state laser" and similar terms may refer to solid state lasers, such as those based on crystalline or glass bodies doped with ions such as transition metal and / or lanthanide ions, fiber lasers, photonic crystal lasers, and semiconductor lasers such as vertical cavity surface emitting lasers (VCSELs).

[0040] The term "solid state light source" and similar terms may refer to semiconductor light sources such as light emitting diodes (LEDs), diode lasers, or superluminescent diodes, among others.

[0041] Instead of the term "solid-state light source," the term "semiconductor-based light source" may also be applied. Thus, the term "semiconductor-based light source" may refer to, for example, one or more of a light-emitting diode (LED), a diode laser, and a superluminescent diode.

[0042] Hence, the light-generating device may comprise one or more of a light-emitting diode (LED), a diode laser, and a superluminescent diode.

[0043] As described above, in embodiments, the first light-generating device may include a first laser light source, such as a diode laser. In embodiments, the first light-generating device may also include a plurality of first laser light sources. In particular, the first light-generating device is configured to generate first device light having a first device light peak wavelength (λ1) and a first spectral power distribution. The term "spectral power distribution" herein particularly refers to a spectral power distribution in the visible wavelength range (see further below). In particular embodiments, the first device light may consist essentially of laser light. In embodiments, the first device light peak wavelength (λ1) may be selected from a wavelength range of 425 to 465 nm. In particular, the first device light peak wavelength (λ1) may be selected from a wavelength range of 430 to 460 nm, more particularly from a wavelength range of 433 to 457 nm, for example, in embodiments, from a wavelength range of 435 to 455 nm. The centroid wavelengths may not have essentially the same value, but the centroid wavelengths may also be found at approximately this wavelength, such as selected from the wavelength range of 435 to 455 nm + / - 5 nm, such as 425 to 465 nm + / - 5 nm.

[0044] Further, as described above, in some embodiments, the second light-generating device may include a second laser light source, such as a diode laser. In some embodiments, the second light-generating device may also include multiple second laser light sources. In particular, the second light-generating device is configured to generate second device light having a second device light peak wavelength (λ2) and a second spectral power distribution. In particular, the second spectral power distribution may be different from the first spectral power distribution. In certain embodiments, the second device light may consist essentially of laser light. In some embodiments, the second device light peak wavelength (λ2) may be selected from the wavelength range of 460 to 490 nm, where λ1<λ2, particularly 470 to 490 nm. In some embodiments, the second device light peak wavelength (λ2) may be selected from the wavelength range of 472 to 487 nm, more particularly 474 to 485 nm, e.g., 475 to 483 nm. The centroid wavelengths may not have essentially the same value, but may also be found at approximately this wavelength, such as selected from the wavelength range of 475-483 nm + / - 5 nm, such as 470-490 nm + / - 5 nm. In particular, the color point may remain relatively close to the blackbody locus, especially at relatively high CCTs, due, inter alia, to the (controllable) contribution of the second device light to the system light.

[0045] In particular, λ2 - λ1 ≧ 10 nm, more particularly λ2 - λ1 ≧ 15 nm. Therefore, in embodiments, the first light-generating device and the second light-generating device may be from different bins (although other choices may be possible when selecting different lasers; see also above). In embodiments, the spectral power distributions of the first device light and the second device light overlap by less than 25%, such as at most 15% (i.e., the first spectral power distribution overlaps by less than 25% with the second spectral power distribution, and the second spectral power distribution overlaps by less than 25% with the first spectral power distribution). More particularly, the spectral power distributions of the first device light and the second device light may overlap by less than 10%, such as less than 5%. Since the first light-generating device and the second light-generating device may comprise lasers, and the first device light and the second device light may essentially consist of laser light (having different spectral power distributions), the spectral overlap may even be essentially zero.

[0046] In certain embodiments, the first device optical peak wavelength (λ1) may be selected from the wavelength range of 430-460 nm, and / or the second device optical peak wavelength (λ2) may be selected from the wavelength range of 475-485 nm. In certain embodiments, λ2-λ1≧20 nm. Furthermore, in certain embodiments, the first centroid wavelength may be selected from the wavelength range of 430-460 nm + / - 5 nm, and / or the second centroid wavelength may be selected from the wavelength range of 475-485 nm + / - 5 nm, and the centroid wavelengths differ by at least about 15 nm, particularly at least about 20 nm.

[0047] The term "centroid wavelength", also referred to as λc, is known in the art and refers to the wavelength value at which half of the light energy is in shorter wavelengths and half of the energy is in longer wavelengths, the value being written in units of nanometers (nm). The centroid wavelength can be calculated by the formula λc=Σλ *The centroid wavelength is the wavelength that divides the integral of the spectral power distribution, as represented by I(λ) / (ΣI(λ)), into two equal parts, where the summation is over the wavelength range of interest and I(λ) is the spectral energy density (i.e., the integral of the wavelength-intensity product over the emission band, normalized to the integrated intensity). The centroid wavelength may be determined, for example, at operating conditions.

[0048] In particular, in embodiments in the blue wavelength range of 440-490 nm, there are only two (narrow) emission bands: one provided by a first device light, having a first device light peak wavelength (λ1), specifically selected from the wavelength range of 430-460 nm, and the other provided by a second device light, having a second device light peak wavelength (λ2), specifically selected from the wavelength range of 475-485 nm. Therefore, in certain embodiments, there is no third emission band available in the range of about 460-475 nm. Therefore, in particular, there may be no third peak between the first device light peak wavelength (λ1) and the second device light peak wavelength (λ2) (or its maximum value may be less than 5% of the maximum value of either the first or second device peak).

[0049] Below, we first discuss some general aspects regarding luminescent materials (in general).

[0050] The term "luminescent material" particularly refers to a material capable of converting a first radiation, in particular one or more of UV radiation and blue radiation, into a second radiation. Generally, the first radiation and the second radiation have different spectral power distributions. Therefore, instead of the term "luminescent material," the term "luminescence converter" or "converter" may also be applied. Generally, the second radiation has a spectral power distribution at a wavelength greater than that of the first radiation, which is the case of so-called down-conversion. However, in certain embodiments, the second radiation has a spectral power distribution with an intensity at a wavelength smaller than that of the first radiation, which is the case of so-called up-conversion.

[0051] In embodiments, the term "luminescent material" may refer specifically to a material capable of converting radiation, for example, into visible light and / or infrared light. For example, in embodiments, the luminescent material may be capable of converting one or more of UV radiation and blue radiation into visible light. The luminescent material may also, in certain embodiments, convert radiation into infrared radiation (IR). Thus, when excited with radiation, the luminescent material emits radiation. Generally, luminescent materials are downconverters, i.e., radiation of a smaller wavelength is converted into radiation having a larger wavelength (λ ex <λ em ), in certain embodiments, the luminescent material may include an upconverter luminescent material, i.e., where radiation of a larger wavelength is converted to radiation having a smaller wavelength (λ ex >λ em ).

[0052] In embodiments, the term "luminescence" may refer to phosphorescence. In embodiments, 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 luminescence (radiation), respectively. Similarly, the term "luminescent material" may, in embodiments, refer to phosphorescence and / or fluorescence.

[0053] The term "luminescent material" may also refer to multiple different luminescent materials. Examples of possible luminescent materials are provided below. Thus, the term "luminescent material" may also refer to a luminescent material composition in certain embodiments. Instead of the term "luminescent material," the term "phosphor" may also be applied. These terms are known to those skilled in the art.

[0054] In embodiments, the luminescent material is selected from garnets and nitrides, particularly doped with trivalent cerium or divalent europium, respectively. The term "nitride" may also refer to oxynitrides or nitridosilicates, etc. Alternatively, or in addition, the luminescent material may be selected from silicates, particularly doped with divalent europium.

[0055] In certain embodiments, the luminescent material is ABO 12 :Ce-type luminescent materials, in which A, in embodiments, 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 B, in embodiments, comprises one or more of Al, Ga, In, and Sc. In particular, A may comprise one or more of Y, Gd, and Lu, in particular one or more of Y and Lu, etc. In particular, B may comprise one or more of Al and Ga, more particularly at least Al, for example essentially entirely Al. Therefore, particularly suitable luminescent materials are cerium-containing garnet materials. Garnet embodiments are particularly those of A3B5O 12The present invention also includes a garnet, wherein A includes at least yttrium or lutetium, and B includes at least aluminum. Such garnets may be doped with cerium (Ce), praseodymium (Pr), or a combination of cerium and praseodymium, but particularly with Ce. In particular, B may include aluminum (Al). In addition to aluminum, B may also include gallium (Ga) and / or scandium (Sc) and / or indium (In), in part, particularly up to about 20% of B, more particularly up to about 10% of B (i.e., 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 particularly include up to about 10% of gallium. In another variation, B and O may be at least partially substituted 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, Gd and / or Tb may in particular only be present in an amount of at most about 20% of A. In certain embodiments, the garnet luminescent material may be selected from the group consisting of (Y 1-x Lu x )3B5O 12 :Ce, where x is greater than or equal to 0 and less than or equal to 1. The term ":Ce" indicates that some of the metal ions in the luminescent material (i.e., in garnets, some of the "A" ions) are replaced by Ce. For example, (Y 1-x Lu x )3AlO 12 In the case of Ce, a portion of Y and / or Lu is substituted by Ce. This is known to those skilled in the art. Ce will generally substitute for A at 10% or less, and the Ce concentration is generally in the range of 0.1 to 4%, particularly 0.1 to 2% (relative to A). Assuming 1% Ce and 10% Y, the complete correct formula is (Y 0.1 Lu 0.89 Ce 0.01 )3AlO 12 The Ce in the garnet is substantially or exclusively in the trivalent state, as known to those skilled in the art.

[0056] In an embodiment, the luminescence material thus contains A3B5O 12 and, in certain embodiments, up to 10% of the B-O may be replaced by Si-N.

[0057] In certain embodiments, the luminescence material is (Y x1 A' x2 Ce x3 )3(Al y1 B' y2 )5O 12 where x1 + x2 + x3 = 1, x3 > 0, 0 < x2 + x3 ≤ 0.2, y1 + y2 = 1, 0 ≤ y2 ≤ 0.2, A' comprises one or more elements selected from the group consisting of lanthanides, and B' comprises 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 to 0.1. In the present invention, particularly x1 > 0, for example, > 0.2 such as at least 0.8. Garnets having Y can provide a suitable spectral power distribution.

[0058] In certain embodiments, up to 10% of the B-O may be replaced by Si-N. Here, B in B-O refers to one or more of Al, Ga, In, and Sc (and O refers to oxygen), and in certain embodiments, B-O may refer to Al-O. As described above, in certain embodiments, x3 may be selected from the range of 0.001 to 0.04. In particular, such luminescence materials have a suitable spectral distribution (however, see also below), have relatively high efficiency, have relatively high thermal stability, and can enable a high CRI (optionally in combination with the light of other light sources as described herein). Therefore, in certain embodiments, A may be selected from the group consisting of Lu and Gd. Alternatively, or additionally, B may include Ga. Therefore, in an embodiment, the luminescence material is (Y x1 (Lu,Gd) x2 Ce x3 )3(Al y1 Ga y2 )5O12 comprising, wherein Lu and / or Gd may be available. More specifically, x3 is selected from the range of 0.001 to 0.1, 0 < x2 + x3 ≦ 0.1, and 0 ≦ y2 ≦ 0.1. Further, in certain embodiments, up to 1% of B-O may be replaced by Si-N. Here, the percentage refers to moles (as is known in the art), for example, see also European Patent No. 3149108. In yet further specific embodiments, the luminescence material is (Y x1-x3 Ce x3 )3Al5O 12 comprising, wherein x1 + x3 = 1 and 0 < x3 ≦ 0.2 such as 0.001 to 0.1.

[0059] In certain embodiments, the light generating device may comprise only a luminescence material selected from the type of cerium-containing garnet. In yet further specific embodiments, the light generating device comprises a single type of luminescence material such as (Y x1 A' x2 Ce x3 )3(Al y1 B' y2 )5O 12 . Therefore, in certain embodiments, the light generating device comprises a luminescence material, and at least 85% by weight, more specifically at least about 90% by weight, and even more specifically at least about 95% by weight, etc. of the luminescence material is (Y x1 A' x2 Ce x3 )3(Al y1 B' y2 )5O 12 . Here, A' comprises one or more elements selected from the group consisting of lanthanides, B' comprises one or more elements selected from the group consisting of Ga, In, and Sc, wherein x1 + x2 + x3 = 1, x3 > 0, 0 < x2 + x3 ≦ 0.2, y1 + y2 = 1, and 0 ≦ y2 ≦ 0.2. In particular, x3 is selected from the range of 0.001 to 0.1. Note that in embodiments, x2 = 0. Alternatively, or further, in embodiments, y2 = 0.

[0060] In certain embodiments, A may particularly include at least Y and B may particularly include at least Al.

[0061] Alternatively, or in addition, the luminescent material may be A3Si6N 11 :Ce 3+ The present invention may include luminescent materials of the type A, where A includes one or more of Y, La, Gd, Tb, and Lu, such as one or more of La and Y, in embodiments.

[0062] In an embodiment, the luminescent material may alternatively or additionally be MS:Eu 2+ and / or M2Si5N8:Eu 2+ and / or MAlSiN3:Eu 2+ and / or Ca2AlSi3O2N5:Eu 2+ and the like, where M includes one or more of Ba, Sr, and Ca, and particularly in embodiments includes at least Sr. Thus, in embodiments, 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 exclusively divalent, substituting one or more of the divalent cations shown. Generally, Eu is not present in an amount greater than 10% of the cations, and its presence will be in the range of about 0.5-10%, more particularly in the range of about 0.5-5%, particularly relative to the substituting cation. The term ":Eu" indicates that a portion of the metal ions is replaced by Eu (in these examples, Eu 2+ For example, assuming 2% Eu in CaAlSiN3:Eu, the correct formula is (Ca 0.98 EU 0.02)AlSiN3. Divalent europium will generally replace a divalent cation, such as the divalent alkaline earth cations mentioned above, particularly Ca, Sr, or Ba. The material (Ba,Sr,Ca)S:Eu can also be designated MS:Eu, where 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 this compound. Here, Eu is introduced to replace at least a portion of M (i.e., one or more of Ba, Sr, and Ca). Furthermore, the material (Ba,Sr,Ca)2Si5N8:Eu can also be designated as M2Si5N8:Eu, where M is one or more elements selected from the group consisting of barium (Ba), strontium (Sr), and calcium (Ca), and in particular M comprises Sr and / or Ba in this compound. In a further particular embodiment, M consists of Sr and / or Ba (not considering the presence of Eu), in particular Ba is 50-100%, more particularly 50-90%, and Sr is 50-0%, in particular 50-10%, e.g. Ba 1.5 Sr 0.5 The material is Si5N8:Eu (i.e., 75% Ba; 25% Sr), where Eu is introduced to replace 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 referred to as MAlSiN3:Eu, where M is one or more elements selected from the group consisting of barium (Ba), strontium (Sr), and calcium (Ca). In particular, M in this compound includes calcium or strontium, or calcium and strontium, more particularly calcium. Wherein Eu is introduced to replace 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 exclusively in a divalent state.

[0063] In embodiments, the red luminescent material may comprise one or more materials selected from the group consisting of (Ba,Sr,Ca)S:Eu, (Ba,Sr,Ca)AlSiN3:Eu, and (Ba,Sr,Ca)2Si5N8:Eu. In these compounds, europium (Eu) is substantially or exclusively divalent, substituting one or more of the divalent cations shown. Generally, Eu is not present in an amount greater than 10% of the cations, and its presence will be in the range of about 0.5-10%, more particularly about 0.5-5%, particularly relative to the substituting cation. The term ":Eu" indicates that a portion of the metal ion is replaced by Eu (in these examples, Eu 2+ For example, assuming 2% Eu in CaAlSiN3:Eu, the correct formula is (Ca 0.98 EU 0.02 )AlSiN3. Divalent europium will generally substitute for a divalent cation such as the divalent alkaline earth cations mentioned above, particularly Ca, Sr, or Ba.

[0064] The material (Ba,Sr,Ca)S:Eu can also be designated as MS:Eu, where M is one or more elements selected from the group consisting of barium (Ba), strontium (Sr), and calcium (Ca), and in particular M comprises calcium or strontium, or calcium and strontium, more particularly calcium, in this compound, where Eu is introduced to replace at least a portion of M (i.e., one or more of Ba, Sr, and Ca).

[0065] Furthermore, the material (Ba,Sr,Ca)2Si5N8:Eu can also be designated as M2Si5N8:Eu, where M is one or more elements selected from the group consisting of barium (Ba), strontium (Sr), and calcium (Ca), and in particular M comprises Sr and / or Ba in this compound. In a further particular embodiment, M consists of Sr and / or Ba (not considering the presence of Eu), in particular Ba is 50-100%, more particularly 50-90%, and Sr is 50-0%, in particular 50-10%, e.g. Ba 1.5 Sr 0.5 Si5N8:Eu (i.e., 75% Ba; 25% Sr), where Eu is introduced to replace at least a portion of M (i.e., one or more of Ba, Sr, and Ca).

[0066] Similarly, the material (Ba,Sr,Ca)AlSiN3:Eu can also be designated as MAlSiN3:Eu, where M is one or more elements selected from the group consisting of barium (Ba), strontium (Sr), and calcium (Ca), and in particular M comprises calcium or strontium, or calcium and strontium, more particularly calcium, in this compound, where Eu is introduced to replace at least a portion of M (i.e., one or more of Ba, Sr, and Ca).

[0067] The Eu in the above-described luminescent materials is substantially or exclusively in a divalent state, as known to those skilled in the art.

[0068] The blue luminescent material is YSO (Y2SiO5:Ce 3+ ), or similar compounds, or BAM (BaMgAl 10 O 17 :EU 2+ , or similar compounds.

[0069] The term "luminescent material" as used herein particularly relates to inorganic luminescent materials.

[0070] Alternatively, or in addition, other luminescent materials may also be applied, for example quantum dots and / or organic dyes, optionally embedded in a transparent matrix, for example a polymer such as PMMA or polysiloxane.

[0071] Quantum dots are small crystals of semiconducting materials, typically only a few nanometers in width or diameter. When excited by incident light, quantum dots emit light whose color is determined by the size and material of the crystal. Therefore, by adjusting the size of the dot, light of a specific color can be generated. Most known quantum dots that emit in the visible range are based on cadmium selenide (CdSe) with a shell such as cadmium sulfide (CdS) and zinc sulfide (ZnS). Cadmium-free quantum dots, such as indium phosphide (InP) and copper indium sulfide (CuInS2) and / or silver indium sulfide (AgInS2), can also be used. Quantum dots exhibit extremely narrow emission bands, and therefore, quantum dots exhibit saturated colors. Furthermore, the emission color can be easily tuned by adjusting the size of the quantum dot. Any type of quantum dot known in the art may be used in the present invention. However, for reasons of safety and environmental concerns, it may be preferable to use cadmium-free quantum dots, or at least quantum dots with very low cadmium content.

[0072] Instead of or in addition to quantum dots, other quantum confinement structures may also be used, the term "quantum confinement structure" being to be understood in the context of the present application as, for example, quantum wells, quantum dots, quantum rods, tripods, tetrapods, or nanowires.

[0073] Organic phosphors can also be used. Examples of suitable organic phosphor materials are organic luminescent materials based on perylene derivatives, such as the compounds sold by BASF under the name Lumogen®. Examples of suitable compounds include, but are not limited to, Lumogen® Red F305, Lumogen® Orange F240, Lumogen® Yellow F083, and Lumogen® F170.

[0074] Different luminescent materials may have different spectral power distributions of their respective luminescent material light. Alternatively, or in addition, such different luminescent materials may have different color points (or dominant wavelengths).

[0075] As mentioned above, other luminescent materials may also be possible. Thus, in certain embodiments, 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. Quantum structures may include, for example, quantum dots or quantum rods (or other quantum-type particles) (see above). Quantum structures may also include quantum wells. Quantum structures may also include photonic crystals.

[0076] As mentioned above, in embodiments the first luminescent material is configured in light receiving relationship with the first light-generating device and therefore may be configured downstream of the first light-generating device.

[0077] The terms "light-receiving relationship" or "light receiving relationship" and similar terms may indicate that an article can receive light from a light source (such as a light-generating device, or a light-generating element, or a light-generating system) during operation of the light source. Thus, the article may be configured downstream of the light source. An optical system may be configured between the light source and the article. The terms "upstream" and "downstream", such as in the context of light propagation, may particularly relate to the positioning of an article or feature with respect to the propagation of light from a light-generating element (here, particularly a first light-generating device), where, relative to a first position in a light beam from the light-generating element, a second position in the light beam that is closer to the light-generating element (than the first position) is "upstream", and a third position in the light beam that is farther away from the light-generating element (than the first position) is "downstream". For example, instead of the term "light-generating element", the term "light-generating means" may also be applied.

[0078] Furthermore, the first luminescent material is configured to convert at least a portion of the first device light (received from the first light-generating device) into first luminescent material light. In particular, the spectral power distribution of the first luminescent material may exhibit an intensity at least within a green-yellow wavelength range when excited by the first device light. Therefore, the first luminescent material light may have an intensity within a wavelength range of 490 to 590 nm. More particularly, the first luminescent material light may have a luminescent material emission centroid wavelength (λ ) within the green-yellow wavelength range, i.e., within the wavelength range of 490 to 590 nm. c,l ).

[0079] The terms "purple light" or "purple emission" and similar terms may particularly relate to light having a wavelength in the range of about 380 to 440 nm. In certain embodiments, purple light may have a centroid wavelength in the range of 380 to 440 nm. The terms "blue light" or "blue emission" and similar terms may particularly relate to light having a wavelength in the range of about 440 to 490 nm (including some purple and cyan hues). In certain embodiments, blue light may have a centroid wavelength in the range of 440 to 490 nm. The terms "green light" or "green emission" and similar terms may particularly relate to light having a wavelength in the range of about 490 to 560 nm. In certain embodiments, green light may have a centroid wavelength in the range of 490 to 560 nm. The terms "yellow light" or "yellow emission" and similar terms may particularly relate to light having a wavelength in the range of about 560 to 590 nm. In certain embodiments, yellow light may have a center wavelength in the range of 560 to 590 nm. The terms "orange light" or "orange emission" and similar terms may particularly refer to light having a wavelength in the range of about 590 to 620 nm. In certain embodiments, orange light may have a center wavelength in the range of 590 to 620 nm. The terms "red light" or "red emission" and similar terms may particularly refer to light having a wavelength in the range of about 620 to 750 nm. In certain embodiments, red light may have a center wavelength in the range of 620 to 750 nm. The terms "cyan light" or "cyan emission" and similar terms may particularly refer to light having a wavelength in the range of about 490 to 520 nm. In certain embodiments, cyan light may have a center wavelength in the range of 490 to 520 nm. The terms "amber light" or "amber emission" and similar terms may particularly refer to light having a wavelength in the range of about 585-605 nm, such as about 590-600 nm. In certain embodiments, amber light may have a centroid wavelength in the range of 585-605 nm. The phrase "light having one or more wavelengths in a wavelength range" and similar terms may particularly indicate that the indicated light (or radiation) has a spectral power distribution with at least an intensity at one or more wavelengths within the indicated wavelength range. For example, a blue-emitting solid-state light source will have a spectral power distribution with an intensity at one or more wavelengths within the wavelength range of 440-495 nm.

[0080] The terms "light" and "radiation" are used interchangeably herein unless it is clear from the context that the term "light" refers only to visible light. Thus, the terms "light" and "radiation" can refer to UV radiation, visible light, and IR radiation. In certain embodiments, particularly those relating to lighting applications, the terms "light" and "radiation" refer to (at least) visible light.

[0081] Thus, in embodiments, a first luminescent material is configured in light receiving relationship with a first light generating device to direct at least a portion of the first device light to a luminescent material emission centroid wavelength (λ ) within the green-yellow wavelength range. c,l ) into a first luminescent material light having a wavelength of 1000 nm. However, in particular, the first luminescent material may not be configured to be in a light-receiving relationship with the second light-generating device. Thus, the first light-generating device, second light-generating device, and first luminescent material (and optional optics) may be configured such that at least a portion of the first device light reaches the first luminescent material, but essentially no second device light reaches the first luminescent material.

[0082] Therefore, in particular, the second device light may bypass the first luminescent material. In this manner, the second device light may not be absorbed by the first luminescent material, but the first luminescent material may, in principle, absorb at least a portion of the second device light if such second device light reaches the first luminescent material. Thus, the first luminescent material may be capable of absorbing (and converting) at least a portion of the first device light, and the first luminescent material may also be capable of absorbing (and converting) at least a portion of the second device light, but may be configured such that the second device light essentially does not reach the first luminescent material.

[0083] Light may bypass the luminescent material when it is not illuminating the luminescent material (in transmission or reflection mode). When light bypasses the luminescent material, it is also not converted by the luminescent material. Thus, in embodiments, the second device light is (essentially) not converted by the first luminescent material (because the second device light may bypass the first luminescent material).

[0084] As described above, the light-generating system may be configured to generate system light that includes one or more of the first device light, the second device light, and the first luminescent material light. In certain embodiments, in certain operating modes of the system, the system light may include all of the first device light, the second device light, and the first luminescent material light.

[0085] In embodiments, the light-generating system may be configured to generate visible light (in one or more modes of operation of the light-generating system). In more particular embodiments, the light-generating system may be configured to generate white light (in one or more modes of operation of the light-generating system).

[0086] The terms "visible," "visible light," or "visible emission," and similar terms, refer to light having one or more wavelengths in the range of approximately 380 to 780 nm. Herein, UV may particularly refer to wavelengths selected from the range of 190 to 380 nm, e.g., 200 to 380 nm. Herein, the term "white light" and similar terms are known to those skilled in the art. White light may particularly refer to light having a correlated color temperature (CCT) between approximately 1800 K and 20,000 K, such as between 2,000 K and 20,000 K, particularly 2,700 to 20,000 K, and particularly within the range of 2,000 to 7,000 K, such as within the range of 2,700 K to 6,500 K for general lighting. For example, in embodiments intended for backlighting or other purposes, the correlated color temperature (CCT) may particularly be in the range of approximately 7,000 K to 20,000 K. Further, in embodiments, the correlated color temperature (CCT) is particularly within about 15 SDCM (standard deviation of color matching) of the black body locus (BBL), particularly within about 10 SDCM of the BBL, and even more particularly within about 5 SDCM of the BBL. In particular embodiments, the correlated color temperature (CCT) may be selected from the range of 6000-12000K, such as from the range of 7000-12000K, or may be at least 8000K. Further, in embodiments, the correlated color temperature (CCT) may be selected from the range of 6000-12000K, such as from the range of 7000-12000K, optionally in combination with a CRI of at least 70.

[0087] In certain embodiments, the system light may have a controllable correlated color temperature. In particular, the spectral power distribution of the system light may be controlled by controlling the first device light and the second device light. Thus, in embodiments, the control system is configured to control the first light-generating device and the second light-generating device.

[0088] In particular, the control system may be configured to: (a) control the first light-generating device and the second light-generating device such that in a first operation mode of the light-generating system, the system light has a first correlated color temperature CCT1, where CCT1≧4000 K. This does not necessarily exclude operation modes in which the first correlated color temperature is less than 4000 K.

[0089] Also, alternatively, or in addition, the control system may be configured to (b) control the first and second light-generating devices in a second operating mode of the light-generating system such that the system light has a second correlated color temperature (CCT2), in embodiments CCT2-CCT1≧500K, more particularly CCT2-CCT1≧1000K, or an even larger (minimum) difference. Again, this does not necessarily exclude operating modes in which CCT2-CCT1≦500K or CCT2-CCT1≦1000K.

[0090] Also, alternatively, or in addition, the control system may be configured to (c) control the first and second light-generating devices so that in at least one of the operating modes, the system light has a correlated color temperature selected from the range of at least 6000 K, more particularly at least 7000 K. Again, this does not necessarily exclude operating modes in which both correlated color temperatures are less than 7000 K, or less than 6000 K. Furthermore, this may also include embodiments including one or more operating modes in which one correlated color temperature is less than 6000 K and the other is greater than 6000 K, or one correlated color temperature is less than 7000 K and the other is greater than 7000 K, particularly embodiments in which the difference in CCT is at least 1000 K, as discussed above. Also, alternatively, or in addition, the control system may be configured to (d) control the first and second light-generating devices so that the system light in both operating modes has a color rendering index of at least 70. Again, this does not necessarily exclude operating modes in which the CRI of one or both of the first and second operating modes is less than 70.

[0091] In certain embodiments, the CCT (of the white light) may be controlled between a first value (CCT1) and a second value (CCT2), where |CCT2−CCT1|≧500K, more particularly |CCT2−CCT1|≧1000K. In certain embodiments, |CCT2−CCT1|≧1500K, |CCT2−CCT1|≧1800K, or more particularly |CCT2−CCT1|≧2000K. In particular, in embodiments, |CCT2−CCT1|≧3000K, such as when the correlated color temperature may be selected from the range of 7000 to 10000K. In embodiments, the CRI across the range of 7000 to 10000K may be at least 70, more particularly at least 80, at least 85, etc. In still further embodiments, the CRI across the range of 7000 to 10000K may be at least 90.

[0092] As mentioned above, a system may include a control system or may be functionally coupled to a control system. The term "controlling" and similar terms particularly refer to at least determining the behavior of an element or managing the operation of an element. Thus, in this specification, "controlling" and similar terms may refer, for example, to imposing a behavior on an element (determining the behavior of an element or managing the operation of an element), such as measuring, indicating, activating, opening, transitioning, changing temperature, etc. Alternatively, the term "controlling" and similar terms may also include monitoring. Thus, the term "controlling" and similar terms may include imposing a behavior on an element, as well as imposing a behavior on an element and monitoring the element. Controlling an element can be performed by a control system, which may also be referred to as a "controller." Thus, the control system and the element may be functionally coupled, at least temporarily or permanently. An element may include a control system. In embodiments, the control system and the element may not be physically coupled. Control can be performed via wired control and / or wireless control. The term "control system" may also refer to a plurality of different control systems, particularly those that are functionally coupled, of which, for example, one control system may be a master control system and one or more other control systems may be slave control systems. A control system may include a user interface or be functionally coupled to a user interface.

[0093] The control system may also be configured to receive and execute instructions from a remote controller. 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. Hence, the device is not necessarily coupled to the lighting system, but may be (temporarily) functionally coupled to the lighting system.

[0094] Therefore, in embodiments, the control system may (also) be configured to be controlled by an app on a remote device. In such embodiments, the control system of the lighting system may be a slave control system or may control in slave mode. For example, the lighting systems may be identifiable by a code, in particular a unique code for each lighting system. The control system of the lighting system may be configured to be controlled by an external control system that has access to the lighting system based on knowledge of the (unique) code (entered by a user interface with an optical sensor (e.g., a QR code reader)). The lighting system may also comprise means for communicating with other systems or devices, such as based on Bluetooth, Thread, WIFI, LiFi, ZigBee, BLE, or WiMAX, or another wireless technology.

[0095] A system, or apparatus, or device may perform an action in a "mode" or "operation mode" or "mode of operation" or "operational mode." The term "operation mode" may also be indicated as a "control mode." Similarly, in a method, an action, or a phase, or a step may be performed in a "mode" or "operation mode" or "mode of operation" or "operational mode." This does not exclude that the system, or apparatus, or device may also be adapted to provide another control mode or multiple other control modes. Likewise, this may not exclude that one or more other modes may be performed before and / or after performing a mode.

[0096] However, in embodiments, a control system adapted to provide at least the control mode may be available. If other modes are available, the selection of such modes may be performed in particular via a user interface, although other options may also be possible, such as executing a mode depending on a sensor signal or a (time) scheme. Operational mode may also refer in embodiments to a system, or apparatus, or device that can only operate in a single operational mode (i.e., "on", without further adjustability).

[0097] Thus, in an embodiment, the control system may be responsive to one or more of a user interface input signal, a sensor signal (of a sensor), and a timer, where the term "timer" may refer to a clock and / or a predetermined time scheme.

[0098] When controlling the CCT, especially at relatively high correlated color temperatures, the color point can stay relatively close to the blackbody locus, such as within 10 SDCM, more particularly within 5 SDCM, or even within about 3 SDCM of the BBL.

[0099] For the first light-generating device, the first luminescent material may be configured in a reflective or transmissive mode.

[0100] The system may further comprise a first optical element configured to focus the first device light onto at least a portion of the first luminescent material. Such a first optical element may be a lens. In an embodiment, the first optical element may be one or two lenses for focusing the first device light onto at least a portion of the first luminescent material. When multiple first light-generating devices are used, a lens array may be used, for example. However, in (other) embodiments, the first optical element may also be a collimator. In such an embodiment, when multiple first light-generating devices are used, a collimator array may be used, for example. Such an array may be contained by a body (such as a (micro)lens plate). Embodiments are also described, for example, in U.S. Patent Application Publication No. 2005 / 0270775, which is incorporated herein by reference.

[0101] Thus, in an embodiment, the first luminescent material is configured in a reflective mode and the light generation system comprises a first optical element configured to focus the first device light onto at least a portion of the first luminescent material. In an alternative embodiment, the first luminescent material may be configured in a transmissive mode and the light generation system comprises a first optical element configured to focus the first device light onto at least a portion of the first luminescent material.

[0102] As described above, the (first) luminescent material may be configured in a reflection mode or a transmission mode. In the transmission mode, it may be relatively easy to mix the source light into the luminescent material light, which may be useful for generating a desired spectral power distribution. In the reflection mode, thermal management may be easier because a significant portion of the luminescent material may be in thermal contact with a thermally conductive element such as a heat sink or heat spreader. In the reflection mode, a portion of the source light may be reflected by the luminescent material and / or a reflector, in embodiments, and mixed into the luminescent material light. (In the reflection mode), the reflector may be configured downstream of the luminescent material. In the reflection mode, a dichroic reflector may be used to enhance the luminescent material light relative to the device light. The former may be transmitted with a higher transmittance than the latter, and the latter may be reflected with a higher reflectance than the former.

[0103] When the pump light can have a spectral power distribution that can be used both to pump the luminescent material and to mix it into the system light, several options can be selected. In embodiments, multiple first light-generating devices can be applied, with one or more being used to pump the luminescent material and one or more other first light-generating devices configured to provide first device light that bypasses the luminescent material. Alternatively, or in addition, one or more first light-generating devices can be used to generate first device light, a portion of which can be directed to the luminescent element and another portion of which can be configured to bypass the luminescent element. This can be done, for example, via a beam splitter. The light can bypass the luminescent element when it is not irradiating the luminescent element (in transmission mode or reflection mode).

[0104] Therefore, it may be useful for some of the first device light to also end up as system light. This may be achieved by one or more of: (i) only partial absorption (and therefore partial reflection and / or transmission); and (ii) bypassing the first luminescent material by some of the first device light. Light that bypasses the (first) luminescent material after reaching it or that is not converted by the (first) luminescent material may be referred to as "unconverted first device light" and similar terms.

[0105] Thus, in embodiments, the first light-generating device and the first luminescent material may be configured such that a portion of the first device light is converted to luminescent material light. Thus, in certain embodiments, the system light may include (i) at least a portion of the unconverted first device light and (ii) the first luminescent material light. More particularly, in embodiments, the system light may include (i) at least a portion of the unconverted first device light, (ii) the second device light, and (iii) the first luminescent material light.

[0106] Thus, in (other) embodiments, a system may include one or more first light-generating devices configured to generate first device light, where the one or more first light-generating devices and optional optics are configured such that a portion of the first device light bypasses the first luminescent material. Thus, in certain embodiments, the system light may include (i) at least a portion of the unconverted first device light and (ii) the first luminescent material light. More particularly, in embodiments, the system light may include (i) at least a portion of the unconverted first device light, (ii) the second device light, and (iii) the first luminescent material light.

[0107] The diversion may be achieved by splitting a beam of first device light into two or more beams, one that propagates to the first luminescent material and another that bypasses the first luminescent material, and / or by using two or more first light-generating devices, where the first device light of one first light-generating device propagates to the first luminescent material and the first device light of another first light-generating device bypasses the first luminescent material. The system comprises a plurality of first light-generating devices, the plurality of first light-generating devices comprising a primary first light-generating device and a secondary first light-generating device, wherein the first luminescent material is configured in light-receiving relationship with one of the primary first light-generating device and the secondary first light-generating device, and the first luminescent material is not configured in light-receiving relationship with the other of the primary first light-generating device and the secondary first light-generating device.

[0108] In embodiments, the first luminescent material may be configured to be in thermal contact with the thermal conductor. Further, in embodiments, the first luminescent material may be contained by the luminescent body. In certain embodiments, the luminescent body may be configured to be in thermal contact with the thermal conductor.

[0109] The thermal conductor may comprise a thermally conductive material. The thermally conductive element may particularly comprise a thermally conductive material. The thermally conductive material may particularly have a thermal conductivity of at least about 20 W / (m * K), for example at least about 30 W / (m * K), at least about 100 W / (m * K), in particular at least about 200 W / (m * In yet more particular embodiments, the thermally conductive material may have a thermal conductivity of at least about 10 W / (m *In embodiments, the thermally conductive material may include one or more of copper, aluminum, silver, gold, silicon carbide, aluminum nitride, boron nitride, aluminum silicon carbide, beryllium oxide, silicon carbide composite, aluminum silicon carbide, copper tungsten alloy, copper molybdenum carbide, carbon, diamond, and graphite. Alternatively, or in addition, the thermally conductive material may include or consist of aluminum oxide.

[0110] The thermal conductor may be a heat sink or a heat spreader. The thermal conductor may be a two-phase cooling device. Heat sinks are known in the art. The term "heat sink" (or heat sink) may particularly refer to a passive heat exchanger that transfers heat generated by a device, such as an electronic or mechanical device, to a fluid (cooling) medium, often air or a coolant. The heat is thereby (at least partially) dissipated from the device. Heat sinks are particularly designed to maximize the surface area of ​​the heat sink that is in contact with the fluid cooling medium surrounding the heat sink. Therefore, a heat sink may particularly comprise multiple fins. For example, a heat sink may be a body from which multiple fins extend. A heat sink particularly includes (more particularly consists of) a thermally conductive material. The term "heat sink" may also refer to multiple (different) heat sinks. A heat spreader may be configured to transfer energy as heat from a first element to a second element. The second element may be, among other things, a heat sink or a heat exchanger. The heat spreader may be passive or active. A passive heat spreader embodiment may comprise a plate or block of a material with high thermal conductivity, such as copper, aluminum, or diamond. An active heat spreader may be configured to consume energy as work provided by an external source to accelerate heat transfer. Herein, the heat spreader may be, among other things, a passive heat spreader. Alternatively, or in addition, the heat spreader may be an active heat spreader selected from the group consisting of a heat pipe and a vapor chamber. The heat spreader may, among other things, comprise a thermally conductive material (more particularly, consist of a thermally conductive material). The term "heat spreader" may also refer to multiple (different) heat spreaders. A two-phase cooling device may be a device that transfers heat between two locations based on both thermal conduction and phase transition. In particular, a liquid such as water (e.g., for a copper device) or acetone (e.g., for an aluminum device) may be added to the two-phase cooling device, and the two-phase cooling device may be vacuum-sealed.When heat is applied to one region of a two-phase cooling device, the liquid may become a vapor and migrate to a lower-pressure region, where it cools back down to a liquid state and migrates back to the heat source. In embodiments, the two-phase cooling device may comprise a heat pipe or vapor chamber element, particularly a heat pipe or vapor chamber element. Vapor chamber elements and heat pipes are known in the art and may be based on essentially the same principles. The difference between a heat pipe and a vapor chamber element may be that a heat pipe typically has an essentially rod shape, while a vapor chamber element generally has a planar shape. In particular, a vapor chamber element may include two essentially planar plates separated by a relatively short distance (e.g., up to 5 mm). Furthermore, while the hot spot can be selected relatively freely in the case of a vapor chamber element, a heat pipe typically has a hot side and a cold side on either side of the rod, such as the base of a cylindrical heat pipe.

[0111] An element may be considered to be in thermal contact with another element if the elements can exchange energy through a thermal process. Therefore, the elements may be thermally coupled. In embodiments, thermal contact may be achieved by physical contact. In embodiments, thermal contact may be achieved through a thermally conductive material, such as a thermally conductive adhesive (or a thermally conductive pressure-sensitive adhesive). Thermal contact may also be achieved between two elements when they are positioned at a distance of about 10 μm or less from each other, although larger distances, such as up to 100 μm, may be possible. The shorter the distance, the better the thermal contact. In particular, the distance is 10 μm or less, e.g., 5 μm or less, e.g., 1 μm or less. The distance may be the distance between two respective surfaces of each element. The distance may also be an average distance. For example, two elements may be in physical contact at one or more locations, such as multiple locations, but not at one or more other locations, particularly multiple other locations. For example, this may be the case when one or both elements have rough surfaces. Thus, in embodiments, the distance between two elements may be 10 μm or less on average (although larger average distances, such as up to 100 μm, may be possible). In embodiments, the two surfaces of the two elements may be kept apart by one or more distance holders. When two elements are in thermal contact, they may be in physical contact or may be configured at a short distance from each other, such as up to 1 mm, such as up to 10 μm. When two elements are configured at a distance from each other, an intermediate material may be configured between them, although in other embodiments, the distance between the two elements may be filled with a gas, liquid, or vacuum. If an intermediate material is available, the greater the distance, the higher the thermal conductivity that may be useful for thermal contact between the two elements. However, the smaller the distance, the lower the thermal conductivity of the intermediate material (although, of course, materials with higher thermal conductivity may also be used).

[0112] The luminescent body may be a layer, such as a self-supporting layer. The luminescent body may also be a coating. The luminescent body may also include a luminescent coating on a support (particularly a light-transmitting support in a transmission mode or a reflective support in a reflection mode). In particular, the luminescent body may be essentially self-supporting. In embodiments, the luminescent material may be provided as a luminescent body, such as a luminescent single crystal, a luminescent glass, or a luminescent ceramic body. Such a body may be referred to as a "converter body" or a "luminescent body." In embodiments, the luminescent body may be a luminescent single crystal or a luminescent ceramic body. For example, in embodiments, a cerium-containing garnet luminescent material may be provided as a luminescent single crystal or a luminescent ceramic body. In other embodiments, the luminescent body may be a light-transmitting body in which the luminescent material is embedded. For example, the luminescent body may be a glass body in which the luminescent material is embedded. Alternatively, the glass itself may be luminescent. In other embodiments, the luminescent body may be a polymer body with a luminescent material embedded therein. The luminescent body may have any shape. However, in general, the luminescent body may have two essentially parallel faces that define the height (of the luminescent body). Furthermore, the luminescent body may have end faces bridging the two essentially parallel faces. The end faces may be curved in one or two dimensions. The end faces may be planar. The luminescent body may have a rectangular or circular cross-section, although other cross-sections, such as hexagonal, octagonal, etc., are also possible. Thus, the luminescent body may have a circular cross-section, an elliptical cross-section, a square cross-section, or a non-square rectangular cross-section. In embodiments, the luminescent body may have an n-gonal cross-section, where n is at least 3, such as 4 (square or rectangular cross-section), 5 (pentagonal cross-section), 6 (hexagonal cross-section), 8 (octagonal cross-section), or more.Two essentially parallel faces may also be referred to as "main faces", in particular as they may provide the largest external area of ​​the luminescent body. There may be another cross section perpendicular to the cross section mentioned above, which may be rectangular in some embodiments. Thus, the luminescent body may have, for example, a cubic shape, a (non-cubic) rectangular parallelepiped shape, an n-gonal prism shape (pentagonal prism, hexagonal prism, etc.) where n is at least 5, and a cylindrical shape. However, other shapes may also be possible. In particular, the luminescent body may have a rectangular parallelepiped shape, a cylindrical shape, or an n-gonal prism shape where n is 6 or 8.

[0113] In embodiments, the luminescent body (or "body") has lateral dimensions of width or length (W1 or L1) or diameter (D), and thickness or height (H1). In embodiments, (i) D≧H1 or (ii) and W1≧H1 and / or L1≧H1. The luminescent body may be transparent or light-scattering. In embodiments, the luminescent body may comprise a ceramic luminescent material. In particular embodiments, L1≦10 mm, particularly L1≦5 mm, more particularly L1≦3 mm, and most particularly L1≦2 mm. In particular embodiments, W1≦10 mm, particularly W1≦5 mm, more particularly W1≦3 mm, and most particularly W1≦2 mm. In particular embodiments, H1≦10 mm, particularly H1≦5 mm, more particularly H1≦3 mm, and most particularly H1≦2 mm. In particular embodiments, D≦10 mm, such as D≦5 mm, more particularly D≦3 mm, and most particularly D≦2 mm. In particular embodiments, the body may have a thickness in the range of 50 μm to 1 mm, in embodiments. Furthermore, the body may have lateral dimensions (width / diameter) in the range of 100 μm to 10 mm. In even more particular embodiments, (i) D>H1 or (ii) W1>H1 and L1>H1. In particular, lateral dimensions such as length, width, and diameter are at least two times greater than the height, such as at least five times. In particular embodiments, the luminescent body has a first length L1, a first height H1, and a first width W1, where H1≦0.5 * L1 and H1≦0.5 *W1. In an embodiment, the luminescent body may be a (small) tile. In an embodiment, the luminescent body may have a first surface, a second surface, and a side surface bridging the first surface and the second surface. The first surface and the second surface may also be referred to as main surfaces. In the case of a cylindrical shape, the side surface may be a single side surface. In the case of a rectangular parallelepiped, the side surface may have four small planes. In the case of a hexagonal prism, the side surface may have six small planes.

[0114] Thus, in an embodiment, the system may comprise (i) a luminescent body including a first luminescent material, and (ii) a first thermal conductor configured to be in thermal contact with the first luminescent material (more particularly, in an embodiment, the first thermal conductor may be configured to be in thermal contact with the luminescent body).

[0115] The thermal conductor may be used to cool the (first) luminescent material, which may be exposed to relatively intense laser light. Alternatively, or in addition, (other) thermal conductors may be used to cool the first light-generating device and / or the second light-generating device. In embodiments, the system may include a laser bank including a plurality of first laser light sources. Alternatively, or in addition, the system may include a laser bank including a plurality of second laser light sources. The laser bank may be configured to be in thermal contact with one or more thermal conductors. In certain embodiments, the system may (further) include (i) a laser bank including a first laser light source, a second laser light source, and (ii) a second thermal conductor configured to be in thermal contact with the first laser light source and the second laser light source. The phrase "laser bank including laser light sources" and similar phrases may also be interpreted as a laser bank hosting laser light sources. Laser banks are known in the art and may also be referred to as "laser array banks."

[0116] The preferred (first) luminescent material may be a cerium-doped garnet-type luminescent material. Such materials are known in the art. In a particular embodiment, the first luminescent material is ABO. 12 The system may comprise a luminescent material of the :Ce type, where A comprises one or more of Y, La, Gd, Tb, and Lu, and B comprises one or more of Al, Ga, In, and Sc. As mentioned above, the system may comprise a luminescent body comprising the first luminescent material. In particular, in an embodiment, the luminescent body is (particularly ABO 12 :Ce 3+ The body may be a ceramic body (containing a luminescent material of this type).

[0117] In order to increase the color rendering index and / or increase the CCT range and / or increase the color gamut of the system light, one or more of a second luminescent material and a third light-generating device may be applied, which may be configured to generate (luminescent material) light in the yellow and / or orange and / or red wavelength range, in particular in the orange-red wavelength range. In particular, such second luminescent material may be configured to (also) convert part of the first device light, although other solutions may also be possible. Thus, in an embodiment, the system (a) converts at least part of the first device light to a second centroid wavelength (λ ), in particular in the yellow-red wavelength range. c,2The optical fiber may further comprise one or more of: (a) a second luminescent material configured to convert the first luminescent material light having a wavelength (λ) of 1000 nm to a second luminescent material light having a wavelength (λ) of 1000 nm; and (b) a third light-generating device comprising a third laser light source and configured to generate third device light having a third device light peak wavelength (λ) and having a third spectral power distribution different from the first spectral power distribution and different from the second spectral power distribution, wherein the third device light peak wavelength (λ) may be selected from a yellow-red wavelength range, particularly an orange-red wavelength range, and more particularly a wavelength range of 600-650 nm. The term "yellow-red wavelength range" may particularly refer to a wavelength range of 560-780 nm. The term "orange-red wavelength range" may particularly refer to a wavelength range of 590-780 nm. In certain embodiments, λ c,1 <λ c,2 For example, in an embodiment, λ c,2 -λ c,1 ≥ 15 nm, λ c,2 -λ c,1 ≧20 nm, more specifically λ c,2 -λ c,1 ≧30 nm.

[0118] It should be noted that the term "third light-generating device" may also refer to multiple (different) third light-generating devices. Similarly, this may apply to the terms "first light-generating device" and "second light-generating device," respectively. Furthermore, the term "second luminescent material" may also refer to multiple different second luminescent materials.

[0119] As noted above, in embodiments, the system may comprise a luminescent body that includes a first luminescent material. In certain embodiments in which the system also comprises a second luminescent material, the luminescent body may (also) comprise the second luminescent material.

[0120] As noted above, in embodiments, the second device light is not (essentially) converted by the first luminescent material (because the second device light may bypass the first luminescent material). Further, in embodiments, the second device light is not (essentially) converted by the second luminescent material (because the second device light may bypass the second luminescent material).

[0121] As mentioned above, the first luminescent material does not have to be configured downstream of the second light-generating device. Because the second device light and the first luminescent material light may be included in the system light (in one or more operating modes of the system), the two types of light may have to be combined. Therefore, in embodiments, the system may further include a beam combiner configured to combine at least a portion of the first device light and at least a portion of the second device light into a beam of device light. In particular, in embodiments, the beam combiner may be selected from the group of dichroic beam combiners and polarizing beam combiners. In embodiments, the light mixing optics may be applied to combine light from different light sources and / or light propagating via different optical paths. In embodiments, the light mixing optics may be one or more of a diffuser (a surface or volume scattering diffuser or an engineered holographic optical element), a light pipe, a light guide, a Kohler integrator optic, etc. Alternatively, or in addition, the light mixing optics may be a collimator or other collimating optics. Alternatively, or in addition, the light mixing optic may be a dichroic beam combiner, such as a dichroic cube in certain embodiments. In embodiments, the light mixing optic may be a dichroic beam splitter.

[0122] It may be desirable to generate a beam of system light that can be relatively collimated. For this purpose, for example, a second optical system may be applied. Such a second optical system may be one or more of a collimator and a lens. Such a second optical system may be configured downstream of the first luminescent material, the first light-generating device, the second light-generating device, the optional second luminescent material, and the optional third light-generating device. In an embodiment, the second optical element may be one or more lenses for collimating the system light. When multiple first light-generating devices are applied, for example, a lens array may be applied. Alternatively, a collimator or an array of collimators may be applied, respectively. Embodiments are also described, for example, in U.S. Patent Application Publication No. 2005 / 0270775, which is incorporated herein by reference.

[0123] Therefore, in an embodiment, the system may further comprise a second optical system configured to beam-shape the system light into a beam (of the system light) having a full width at half maximum of at most 5°, more particularly at most 3°, and even more particularly at most 2°, at most about 1.5°, etc.

[0124] As discussed above, it may be desirable to control the correlated color temperature of the system light. In certain embodiments, the control system may be configured to control the first and second light-generating devices (and optional third light-generating device) in a (third) mode of operation of the light-generating system such that the system light has a correlated color temperature selected from a range of at least 6000 K, such as at least 6500 K, such as selected from a range of 7000-10000 K. In certain embodiments, the system light may have a correlated color temperature selected from a range of at least 7500 K, such as at least about 7800 K. Also, in certain embodiments, the system light may have a correlated color temperature selected from a range of at least 8000 K. In embodiments, such a (third) mode of operation may comprise a second mode of operation as described herein, although in other embodiments it may also comprise the first mode of operation. Notably, the first mode of operation and the second mode of operation do not overlap in time.

[0125] In an embodiment, in one of the operating modes of the light-generating system, the system light may have a spectral power distribution in the visible wavelength range, with at least 5% of the spectral power provided by the second device light, at least 25% of the spectral power distribution provided by the first device light, and at least 30% of the spectral power distribution provided by the first luminescent material light. Alternatively, or in addition, in (another) one of the operating modes of the light-generating system, the system light may have a spectral power distribution in the visible wavelength range, with less than 1% of the spectral power provided by the second device light, at least 25% of the spectral power distribution provided by the first device light, and at least 30% of the spectral power distribution provided by the first luminescent material light.

[0126] In an embodiment, in one mode of operation, the control system may control the system light such that the radiant flux of the system light is increased when the correlated color temperature is increased and decreased when the correlated color temperature is decreased, which may also be referred to as "BBL dimming."

[0127] The light-generating system may be part of or applied to, for example, an office lighting system, a home application system, a store lighting system, a domestic lighting system, an accent lighting system, a spot lighting system, a theatrical lighting system, a fiber optic application system, a projection system, a self-illuminated display system, a pixelated display system, a segmented display system, a warning sign system, a medical lighting application system, an indicator sign system, a decorative lighting system, a portable system, an automotive application, an (outdoor) road lighting system, an urban lighting system, a greenhouse lighting system, horticultural lighting, digital projection, or LCD backlighting. The light-generating system (or luminaire) may be part of or applied to, for example, an optical communication system or a disinfection system.

[0128] In a still further aspect, the present invention also provides a lamp or luminaire comprising a light-generation system as defined herein. The luminaire may further comprise a housing, optical elements, louvers, etc. The lamp or luminaire may further comprise a housing enclosing the light-generation system. The lamp or luminaire may comprise an optical window in the housing or a housing opening through which the system light may escape the housing. In a still further aspect, the present invention also provides a projection device comprising a light-generation 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-generation systems as described herein. Thus, in one aspect, the present invention also provides a light-generation device selected from the group consisting of a lamp, a luminaire, a projector device, a disinfection device, a photochemical reactor, and an optical wireless communication device, comprising a light-generation system as defined herein. The light-generation device may comprise a housing or support configured to accommodate or support one or more elements of the light-generation system. For example, in an embodiment, the light-generating device may comprise a housing or support configured to contain or support the first light-generating device, the second light-generating device, the first luminescent material, and optionally one or more of the other components as described above.

[0129] In particular, the lamp or luminaire may be configured for stage lighting. Thus, in one aspect, the present invention also provides a method for providing light to a stage, the method comprising generating system light using a light generation system as described herein in a space including the stage. The stage may be indoors, such as a theatre, but may also be outdoors, such as a stadium or festival stage, or TV studio lighting. [Brief explanation of the drawings]

[0130] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts and in which: [Figure 1] 1 illustrates several embodiments in a schematic manner. [Figure 2a] 1 illustrates several embodiments in a schematic manner. [Figure 2b] 1 illustrates several embodiments in a schematic manner. [Figure 3] Some application embodiments are illustrated schematically. The schematic drawings are not necessarily to scale. DETAILED DESCRIPTION OF THE INVENTION

[0131] 1 shows six possible embodiments, with reference to which a light-generating system 1000 is shown, comprising a first light-generating device 110, a second light-generating device 120, and a first luminescent material 210. Additionally, a control system 300 may be available, although it is not depicted in all embodiments.

[0132] The first light-generating device 110 may comprise a first laser light source 10 and may be configured to generate a first device light 111 (see also FIG. 2a) having a first device light peak wavelength λ1 and a first spectral power distribution. The first device light peak wavelength λ1 may be selected from a wavelength range of 425-465 nm. The second light-generating device 120 may comprise a second laser light source 20 and may be configured to generate a second device light 121 (see also FIG. 2a) having a second device light peak wavelength λ2 and a second spectral power distribution different from the first spectral power distribution. The second device light peak wavelength (λ2) may be selected from a range of 470-490 nm. The first luminescent material 210 may be configured in a light-receiving relationship with the first light-generating device 110 and may transmit at least a portion of the first device light 111 to a luminescent material emission centroid wavelength λ2 in the green-yellow wavelength range. c,lThe first luminescent material 210 may be configured to convert the first device light 111, the second device light 121, and the first luminescent material light 211 (see also FIG. 2a) having a color temperature that is controllable. The first luminescent material 210 may not be configured to be in a light-receiving relationship with the second light-generating device 120. In particular, the light-generating system 1000 may be configured to generate a system light 1001 that includes one or more of the first device light 111, the second device light 121, and the first luminescent material light 211. The system light 1001 has a controllable correlated color temperature. A control system indicated by reference numeral 300 (see, for example, embodiments V to VI, although such a control system 300 may of course also be usable in the schematically illustrated embodiments I to IV) may be configured to control the first light-generating device 110 and the second light-generating device 120 so that one or more of the following may be applied: (a) in a first operating mode of the light-generating system 1000, the system light 1001 has a first correlated color temperature CCT1, where CCT1≧4000K; (b) in a second operating mode of the light-generating system 1000, the system light 1001 has a second correlated color temperature (CCT2), where CCT2−CCT1≧1000K; (c) in at least one of the operating modes, the system light 1001 has a correlated color temperature selected from a range of at least 7000K; and (d) in both operating modes, the system light 1001 has a color rendering index of at least 70.

[0133] In an embodiment, the first light-generating device 110 and the first luminescent material 210 may be configured such that a portion of the first device light 111 may be converted to luminescent material light 211. In an embodiment, the system light 1001 may include (i) at least a portion of the unconverted first device light 111, (ii) the second device light 121, and (iii) the first luminescent material light 211.

[0134] In embodiments (see, for example, embodiments II-VI), the light-generation system 1000 may comprise one or more first light-generating devices 110 configured to generate a first device light 111. The one or more first light-generating devices 110 and the optional optical system 400 may be configured such that a portion of the first device light 111 bypasses the first luminescent material 210. In embodiments, the system light 1001 may include (i) at least a portion of the first device light 111 that bypasses the first luminescent material 210, (ii) the second device light 121, and (iii) the first luminescent material light 211. Thus, in embodiments, the light-generation system 1000 may comprise a plurality of first light-generating devices 110. The plurality of first light-generating systems 110 may comprise a primary first light-generating device 1110 and a secondary second light-generating device 2110. The first luminescent material 210 may be configured to be in a light-receiving relationship with one of the primary first light-generating device 1110 and the secondary first light-generating device 2110, and the first luminescent material may not be configured to be in a light-receiving relationship with the other of the primary first light-generating device 1110 and the secondary first light-generating device 2110.

[0135] In embodiments, the light-generation system 1000 may comprise a luminescent body 1200 comprising a first luminescent material 210. Alternatively, or in addition, in embodiments, the light-generation system 1000 may comprise a first thermal conductor 505 configured to be in thermal contact with the first luminescent material 210. In particular, in embodiments, the first thermal conductor 505 may be configured to be in thermal contact with the luminescent body 1200. Furthermore, in embodiments, the light-generation system 1000 may comprise a laser bank 550 comprising a first laser light source 10, a second laser light source 20, and a second thermal conductor 555 configured to be in thermal contact with the first laser light source 10 and the second laser light source 20. (See schematically illustrated embodiments V-VI).

[0136] In certain embodiments, first luminescent material 210 may be configured in a transmissive mode (see, e.g., Embodiments I-II). In certain (other) embodiments, first luminescent material 210 may be configured in a reflective mode (see, e.g., Embodiments III-VI).

[0137] The light-generating system 1000 may comprise a first optical element 420 configured to focus the first device light 111 onto at least a portion of the first luminescent material 210. In an embodiment, the luminescent material 210 is ABO 12 :Ce type luminescent material, where 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 an embodiment, a luminescent body 1200, such as a ceramic body, may include a first luminescent material 210.

[0138] In certain embodiments, the light-producing system 1000 condenses at least a portion of the first device light 111 into a second centroid wavelength (λ ) of the yellow-red wavelength range. c,2 ) into a second luminescent material light 221 having a wavelength λ c,1 <λ c,2 may be applied. Several configurations of the second luminescent material 220 may be possible. This is shown schematically in FIG. 2b in relation to an embodiment in which the first luminescent material 210 and the second luminescent material 220 are combined, for example, in a luminescent body. Thus, in an embodiment, the luminescent body 1200 may comprise the second luminescent material 220. As mentioned above, in an embodiment, the luminescent body 1200 may be a ceramic body.

[0139] Alternatively, or in addition, in certain embodiments, the light-generating system 1000 may further comprise a third light-generating device 130 comprising a third laser light source 30 and configured to generate third device light 131 having a third device light peak wavelength (λ3) and having a third spectral power distribution different from the first spectral power distribution and different from the second spectral power distribution. This is shown schematically in embodiment VI of Figure 1. The third device light peak wavelength λ3 may be selected from the range of 600-650 nm (see also Figure 2a).

[0140] In certain embodiments, the light-generation system 1000 may further comprise a beam combiner 410 configured to combine at least a portion of the first device light 111 and at least a portion of the second device light 121 into a beam of device light 111, 121. The term "beam combiner" may also refer to multiple beam combiners. One or more additional beam combiners 410 may be applied if additional beams of light, for example from an optional third light-generation device, are available. The beam combiner 410 may be selected from the group of a dichroic beam combiner and a polarization beam combiner.

[0141] In an embodiment, the light-generation system 1000 may further comprise a second optical system 430 configured to beam-shape the system light 1001 into a beam having a full width at half maximum of at most 2°, although other beam angles α are not excluded herein. The second optical system may, for example, be a collimator. With reference to embodiments I and II, in which these second optical systems 430 are shown schematically, reference symbol O refers to the optical axis. When the radiant flux is plotted perpendicular to this optical axis, the full width at half maximum may result in a beam angle α of, for example, 2°.

[0142] As mentioned above, the light-generating system 1000 may include a control system. In an embodiment, the control system 300 may be configured to control the first light-generating device 110 and the second light-generating device 120 (and the optional third light-generating device 130) in a particular embodiment, in an operating mode of the light-generating system 1000, such that the system light 1001 has a correlated color temperature selected from the range of 7000 to 10000 K.

[0143] In an embodiment, in one of the operating modes of the light generation system 1000, the system light 1001 has a spectral power distribution in the visible wavelength range, and at least 5% of the spectral power may be provided by the second device light 121, at least 25% of the spectral power distribution may be provided by the first device light 111, and at least 30% of the spectral power distribution may be provided by the first luminescent material light 201.

[0144] In an embodiment, in one of the operating modes of the light generation system 1000, the system light 1001 has a spectral power distribution in the visible wavelength range, and less than 1% of the spectral power may be provided by the second device light 121, at least 25% of the spectral power distribution may be provided by the first device light 111, and at least 30% of the spectral power distribution may be provided by the first luminescent material light 201.

[0145] In an embodiment, in an operating mode, the control system 300 controls the system light 1001 so that the radiant flux of the system light 1001 can be increased when the correlated color temperature is increased and the radiant flux of the system light 1001 can be decreased when the correlated color temperature is decreased.

[0146] Referring also to FIG. 2a, one or more of the following may be applied: (i) the first device optical peak wavelength λ1 may be selected from the wavelength range of 430 to 460 nm; and (ii) the second device optical peak wavelength λ2 may be selected from the wavelength range of 475 to 485 nm. As shown schematically, the spectral overlap is essentially 0%. Furthermore, there may be no third peak between the first device optical peak wavelength λ1 and the second device optical peak wavelength λ2.

[0147] 2b, there is shown schematically an embodiment of a luminescent body 1200 comprising a first luminescent material 210 and an optional second luminescent material 220. Reference number 200 generally refers to the luminescent materials. Furthermore, there is shown schematically an embodiment in which the second device light 121 bypasses the first luminescent material 210 (and the second luminescent material 220). Furthermore, there is shown schematically an embodiment in which the first device light 111 is partially transmitted by the first luminescent material 210 (and the second luminescent material 220) (more particularly by the luminescent body 1200) and partially converted by the first luminescent material 210 (and the second luminescent material 220) to first luminescent material light 211 (and second luminescent material light 221).

[0148] FIG. 3 schematically illustrates an embodiment of a lighting fixture 2 comprising a light-generating system 1000 as described above. Reference number 301 indicates a user interface, which may be functionally coupled to a control system 300 included by or functionally coupled to the light-generating system 1000. FIG. 3 also schematically illustrates an embodiment of a lamp 1 comprising the light-generating system 1000. Reference number 3 indicates a projector device or projector system, which may be used to project images onto a wall or the like, and which may also comprise the light-generating system 1000. Thus, FIG. 3 schematically illustrates an embodiment of a lighting device 1200 selected from the group of a lamp 1, a lighting fixture 2, a projector device 3, a disinfection device, a photochemical reactor, and an optical wireless communication device, comprising the light-generating system 1000 as described herein. In an embodiment, such a lighting device may be a lamp 1, a lighting fixture 2, a projector device 3, a disinfection device, or an optical wireless communication device. Light escaping from the lighting device 1200 is indicated by reference number 1201. The lighting device light 1201 may consist essentially of, and therefore in certain embodiments may be, the system light 1001. Reference numeral 1300 refers to a space such as a room. Reference numeral 1305 refers to the floor, reference numeral 1310 refers to the ceiling, and reference numeral 1307 refers to the walls.

[0149] The term "plurality" refers to two or more.

[0150] The terms "substantially" or "essentially" and similar terms used herein will be understood by those skilled in the art. The terms "substantially" or "essentially" can also include embodiments with "entirely," "completely," "all," etc. Thus, in embodiments, the adjectives substantially or essentially may also be omitted. Where applicable, the terms "substantially" or "essentially" can also relate to 90% or more, including 100%, such as 95% or more, particularly 99% or more, and even more particularly 99.5% or more.

[0151] The term "comprises" also includes embodiments in which the term "comprises" means "consists of."

[0152] The term "and / or" specifically relates to one or more of the items mentioned before and after "and / or." For example, the phrase "item 1 and / or item 2" and similar phrases may relate to one or more of items 1 and 2. The term "comprising" may, in some embodiments, refer to "consisting of," but in other embodiments may also refer to "including at least the defined species, and optionally one or more other species."

[0153] Furthermore, terms such as first, second, third, etc., used in the specification and claims are used to distinguish between similar elements and not necessarily to describe a sequential or chronological order. The terms so used are interchangeable under appropriate circumstances, with the understanding that the embodiments of the invention described herein are capable of operating in other sequences than those described or illustrated herein.

[0154] As used herein, a device, apparatus, or system may be described, among other things, in operation. As will be apparent to those skilled in the art, the present invention is not limited to methods of operation or to devices, apparatus, or systems in operation.

[0155] It should be noted that the above-described embodiments are illustrative rather than limiting of 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.

[0156] In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

[0157] Use of the verb "to comprise" and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. Unless the context clearly requires otherwise, throughout the specification and claims, the words "comprise", "comprising", and the like are to be interpreted in an inclusive sense, i.e., "including but not limited to", rather than an exclusive or exhaustive sense.

[0158] The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

[0159] 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, apparatus claim or system claim enumerating several means, several of these means may be embodied by one and the same item of hardware. The mere fact that certain means are recited in mutually different dependent claims does not indicate that a combination of these means cannot be used to advantage. In a still further aspect, the invention therefore provides a software product which, when executed on a computer, is capable of causing (one or more embodiments of) the method as described herein.

[0160] The present invention also provides a control system that may control a device, apparatus, or system or that may perform the methods or processes described herein. Still further, the present invention also provides a computer program operatively coupled to or contained by a device, apparatus, or system, which, when executed on a computer, controls one or more controllable elements of such a device, apparatus, or system.

[0161] The present invention further applies to a device, apparatus or system comprising one or more of the characterizing features described in the present description and / or shown in the accompanying drawings. The present invention further relates to a method or process comprising one or more of the characterizing features described in the present description and / or shown in the accompanying drawings.

[0162] The various aspects discussed in this patent may be combined to provide additional advantages. Moreover, those skilled in the art will appreciate that embodiments may be combined, and that three or more embodiments may be combined. Furthermore, some of the features may form the basis for one or more divisional applications.

Claims

1. 1. A light-generating system comprising a plurality of first light-generating devices, a second light-generating device, a first luminescent material, and a control system, the plurality of first light-generating devices comprise a first laser light source and are configured to generate first device light having a first device light peak wavelength and a first spectral power distribution, the first device light peak wavelength being selected from a wavelength range of 425 to 465 nm; the second light-generating device comprises a second laser light source and is configured to generate second device light having a second device light peak wavelength and a second spectral power distribution different from the first spectral power distribution, the second device light peak wavelength being selected from a range of 470 to 490 nm; The first luminescent material is configured in light receiving relationship with the first light generating device and emits at least a portion of the first device light at a luminescent material emission centroid wavelength λ in the green-yellow wavelength range. ｃ，ｌ a first luminescent material configured to convert light having a wavelength of about 100 nm into light having a wavelength of about 100 nm, the first luminescent material being configured to be out of light receiving relationship with the second light generating device; the plurality of first light-generating devices comprises a primary first light-generating device and a secondary first light-generating device, the first luminescent material is configured to be in light-receiving relationship with one of the primary first light-generating device and the secondary first light-generating device, and the first luminescent material is configured to be out of light-receiving relationship with the other of the primary first light-generating device and the secondary first light-generating device; the light-producing system is configured to produce system light including one or more of the first device light, the second device light, and the first luminescent material light, the system light having a controllable correlated color temperature; 1. A light-generating system, comprising: a) a control system configured to control the first light-generating device and the second light-generating device such that: (a) in a first operating mode of the light-generating system, the system light has a first correlated color temperature CCT1, where CCT1≧4000K; (b) in a second operating mode of the light-generating system, the system light has a second correlated color temperature CCT2, where CCT2−CCT1≧1000K; (c) in at least one of these operating modes, the system light has a correlated color temperature selected from a range of at least 7000K; and (d) the system light in both operating modes has a color rendering index of at least 70.

2. 2. The light-generating system of claim 1, wherein the first light-generating device and the first luminescent material are configured such that a portion of the first device light is converted to the luminescent material light, and the system light comprises (i) at least a portion of the unconverted first device light, (ii) the second device light, and (iii) the first luminescent material light.

3. 3. The light generation system of claim 1, wherein the system light comprises: (i) at least a portion of the first device light that bypasses the first luminescent material; (ii) the second device light; and (iii) the first luminescent material light.

4. 4. The light-generation system of claim 1, comprising: (i) a luminescent body comprising the first luminescent material; (ii) a first thermal conductor configured to be in thermal contact with the first luminescent material; and (iii) a laser bank comprising the first laser light source, the second laser light source, and a second thermal conductor configured to be in thermal contact with the first laser light source and the second laser light source.

5. The light-generating system of claim 4 , wherein the luminescent body comprises a ceramic body.

6. 6. The light generation system of claim 1, wherein the first luminescent material is configured in a reflective mode, and the light generation system comprises a first optical element configured to focus the first device light onto at least a portion of the first luminescent material.

7. 6. The light generation system of claim 1, wherein the first luminescent material is configured in a transmission mode, and the light generation system comprises a first optical element configured to focus the first device light onto at least a portion of the first luminescent material.

8. The first luminescent material is A ３ B ５ O １２ 8. The light-generating system of claim 1 , comprising a luminescent material of the :Ce type, wherein A comprises one or more of Y, La, Gd, Tb, and Lu, and B comprises one or more of Al, Ga, In, and Sc.

9. and at least a portion of the first device light is focused at a second centroid wavelength λ in the yellow-red wavelength range. ｃ，２ a second luminescent material configured to convert light having a wavelength of λ ｃ，１ <λ ｃ，２ a second luminescent material, a third light-generating device comprising a third laser light source and configured to generate third device light having a third device light peak wavelength and a third spectral power distribution different from the first spectral power distribution and different from the second spectral power distribution, wherein the third device light peak wavelength is selected from the range of 600 to 650 nm; 9. The light-generating system of claim 1, further comprising one or more of:

10. 10. The light-generation system of claim 1, further comprising a beam combiner configured to combine at least a portion of the first device light and at least a portion of the second device light into a beam of device light, the beam combiner being selected from the group of a dichroic beam combiner and a polarization beam combiner.

11. 11. The light-generating system of any one of claims 1 to 10, further comprising a second optical system configured to beam-shape the system light into a beam having a full width at half maximum of up to 2°, wherein the first device optical peak wavelength is selected from a wavelength range of 430 to 460 nm and / or the second device optical peak wavelength is selected from a wavelength range of 475 to 485 nm.

12. 12. The light-generating system of claim 1, wherein the control system is configured to control the first light-generating device and the second light-generating device such that, in an operational mode of the light-generating system, the system light has a correlated color temperature selected from the range of 7000 to 10000 K.

13. in one of the operating modes of the light-generating system, the system light has a spectral power distribution in the visible wavelength range, at least 5% of the spectral power distribution is provided by the second device light, at least 25% of the spectral power distribution is provided by the first device light, and at least 30% of the spectral power distribution is provided by the first luminescent material light; and / or In one of the operating modes of the light generation system, the system light has a spectral power distribution in the visible wavelength range, less than 1% of the spectral power distribution is provided by the second device light, at least 25% of the spectral power distribution is provided by the first device light, and at least 30% of the spectral power distribution is provided by the first luminescent material light.

13. A light production system according to any one of claims 1 to 12.

14. 14. The light generating system of claim 1, wherein in an operational mode, the control system controls the system light such that the radiant flux of the system light is increased when the correlated color temperature is increased and the radiant flux of the system light is decreased when the correlated color temperature is decreased.

15. 15. A lighting device selected from the group of a lamp, a luminaire and a projector device, comprising a light production system according to any one of claims 1 to 14.

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