Laser phosphor based stage lighting engine with efficient polarization maintaining diffuser configuration

Abstract

The invention provides a light generating system (1000) comprising (i) one or more light generating devices (100), (ii) a luminescence conversion arrangement (2000), and (iii) a diffuser arrangement (4000), where the one or more light generating devices (100) are configured to generate device light (101); wherein the one or more light generating devices (100) comprise a solid state light source (10), wherein the solid state light source (10) comprises one or more of a laser diode and a super light emitting diode; wherein the light generating system (1000) is configured such that, in an operating mode of the light generating system (1000), (a) at least a portion of the device light (101) propagates to the luminescence conversion arrangement (2000), and (b) at least a portion of the device light (101) propagates to the diffuser arrangement (4000); wherein at least a portion of the device light (101) propagating to the diffuser arrangement (4000) is polarized light comprising one of a first linear polarization and a second linear polarization; the luminescent conversion arrangement (2000) comprises a luminescent material (200) configured to convert at least a portion of the device light (101) received by the luminescent material (200) into luminescent material light (201); wherein the luminescent material (200) is configured in a reflective mode with respect to the device light (101) illuminating the luminescent material (200); the diffuser arrangement (4000) is configured to generate diffused device light (401) from at least a portion of the device light (101) received by the diffuser arrangement (4000); wherein the diffuser arrangement (4000) comprises a polarization beam splitter (410), a quarter wave plate (420), a polarization maintaining diffuser (430) and a specular mirror (440), wherein the mirror (440) comprises a metal mirror (440); a polarizing beam splitter (410) (i) having transmissivity for one of the light having the first linear polarization and the light having the second linear polarization, and (ii) having reflectivity for the other of the light having the first polarization and the light having the second linear polarization; and the light generating system (1000) is configured to generate system light (1001), the system light (1001) comprising (i) diffused device light (401) and (ii) luminescent material light (201) in an operating mode of the light generating system (1000).

Description

Technical Field

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

[0002] Laser-phosphor-based stage lighting engines are known in the art. For example, WO2022143318 describes a light-emitting device comprising a first light source, a second light source, a dichroic reflector, a wavelength conversion device, a first optical path adjustment device or a second optical path adjustment device, and a first scattering optical system. In the present invention, the use of the first scattering optical system improves the light mixing effect of the emitted light. By independently adjusting the power of the first and second light sources, the color temperature of the light emitted by the light-emitting device can be freely adjusted. The second light source can use a laser that emits light of different dominant wavelengths to improve the color rendering index of the light emitted by the light-emitting device. The light emitted by the first light source in the present invention is used to excite the wavelength conversion device. Compared with existing solutions, the light-emitting device provided by the present invention can achieve higher luminous flux output without increasing the optical etendue. Furthermore, if a polarization-selective element is used in a matching mode in the first light source, the luminous flux output of the light-emitting device can be further increased. Summary of the Invention

[0003] High brightness light sources can be used in a variety of applications including spotlights, stage lighting, headlights, furniture and office lighting, and automotive lighting.For this purpose, laser-phosphor technology can be used, in which a laser provides the laser light and a remote phosphor converts the laser light into converted light.

[0004] A relatively straightforward approach to generating white light using lasers is to combine blue laser light with phosphor-converted light. However, current laser lighting fixtures cannot produce a strong beam safely and with good performance. For example, damage to the optics can lead to the outcoupling of high-intensity light. With the demand for compact, high-power devices, other issues associated with these laser sources may also arise.

[0005] Therefore, one aspect of the present invention is to provide an alternative light generating system which preferably further at least partially obviates one or more of the disadvantages described above. It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art or to provide a useful alternative.

[0006] According to a first aspect, the present invention provides a light generating system ("system") comprising one or more light generating devices, a luminescence conversion arrangement and a diffuser arrangement. The one or more light generating devices may be particularly configured to generate device light. In particular, the one or more light generating devices may comprise a (solid-state) light source. More particularly, the (solid-state) light source may comprise one or more of a laser diode and a superluminescent diode. Further, in various embodiments, the light generating system may be configured such that: (in an operating mode of the light generating system), (a) at least a portion of the device light propagates to the luminescence conversion arrangement, and (b) at least a portion of the device light propagates to the diffuser arrangement. In particular, at least a portion of the device light of the device light that propagates to the diffuser arrangement comprises polarized light, the polarized light comprising one of a first (linear) polarization and a (linear) second polarization. Further, in various embodiments, the luminescence conversion arrangement may comprise a luminescent material configured to convert at least a portion of the device light received by the luminescent material into luminescent material light. In particular, the luminescent material may be configured in a reflective mode relative to the device light illuminating the luminescent material. Still further, in various embodiments, the diffuser arrangement may be configured to generate diffused device light from at least a portion of the device light received by the diffuser arrangement. In particular, the system (more particularly, the diffuser arrangement) may include a polarization beam splitter, a quarter wave plate, a polarization-maintaining diffuser, and a reflector. Herein, the reflector may in particular be a specular reflector. More particularly, the reflector may include a metal reflector. Further, the polarization beam splitter may: (i) be transmissive to one of light having a first polarization and light having a second polarization, and (ii) be reflective to the other of the light having the first polarization and light having the second polarization. Further, in various embodiments, the quarter wave plate may be configured between the beam splitter and the polarization-maintaining diffuser. Further, in various embodiments, the polarization-maintaining diffuser may be configured between the quarter wave plate and the (specular) reflector. In particular, the polarization-maintaining diffuser may be configured as a diffuser for device light having the polarization device light applied to the device light by the quarter wave plate. Furthermore, the one or more secondary optical elements can be configured to collimate the device light. In particular, one of the following may apply: (i) a primary secondary optical element can be configured between at least one of the one or more light-generating devices and the luminescent material, and (ii) a secondary optical element can be configured between the quarter-wave plate and the diffuser. Still further, the light-generating system can be configured to generate system light that (in an operating mode of the light-generating system) includes diffused device light and luminescent material light.Thus, in a particular embodiment, the present invention provides a light generating system comprising (i) one or more light generating devices, (ii) a luminescent conversion arrangement and (iii) a diffuser arrangement, wherein the one or more light generating devices are configured to generate device light, wherein the one or more light generating devices comprise a solid-state light source, wherein the solid-state light source comprises one or more of a laser diode and a superluminescent diode; wherein the light generating system is configured such that: in an operating mode of the light generating system, (a) at least a portion of the device light propagates to the luminescent conversion arrangement, and (b) at least a portion of the device light propagates to the diffuser arrangement; wherein at least a portion of the device light propagating to the diffuser arrangement is polarized light comprising one of a first (linear) polarization and a second (linear) polarization; wherein the luminescent conversion arrangement comprises a luminescent material, which is configured to convert at least a portion of the device light received by the luminescent material into luminescent material light; wherein the luminescent material is configured in a reflective mode relative to the device light irradiating the luminescent material; wherein the diffuser arrangement is configured to: generate diffused device light from at least a portion of the device light received by the diffuser arrangement; wherein the diffuser arrangement The device comprises: a polarization beam splitter, a quarter wave plate, a polarization-maintaining diffuser, and a specular reflector, wherein the reflector comprises a metal reflector; wherein the polarization beam splitter: (i) is transmissive to one of light having a first polarization and light having a second polarization, and (ii) is reflective to the other of the light having the first polarization and the light having the second polarization; wherein the quarter wave plate is disposed between the beam splitter and the polarization-maintaining diffuser; the polarization-maintaining diffuser is disposed between the quarter wave plate and the specular reflector; wherein the polarization-maintaining diffuser is configured as a diffuser for device light, the device light having the polarization applied by the quarter wave plate polarized device light to device light; wherein the one or more second optical elements are configured to collimate the device light, wherein one or more of the following apply: (i) a primary second optical element configured between at least one of the one or more light generating devices and the luminescent material, and (ii) a secondary second optical element configured between the wave plate and the diffuser; and wherein the light generating system is configured to generate system light that, in an operating mode of the light generating system, includes (i) the diffused device light and (ii) the luminescent material light.

[0007] The present invention can provide high-intensity white light. Furthermore, the present invention can enable the generation of high-intensity light with a reduced risk of this light escaping the system if optical components are damaged or destroyed. Thus, the proposed system can improve the safety of laser generation systems. Thus, the present invention can provide a laser phosphor-based stage lighting engine with a highly efficient polarization-maintaining diffuser arrangement.

[0008] As mentioned above, the present invention provides a light generating system, which in various embodiments includes one or more light generating devices, a luminescence conversion arrangement, and a diffuser arrangement. Embodiments of these elements are described in more detail below.

[0009] In various embodiments, one or more light generating devices may comprise a (solid-state) light source, see also below. Each light generating device may comprise one or more (solid-state) light sources. In particular, one or more light generating devices may be configured to generate device light. The device light may in particular have a wavelength selected from the visible wavelength range (i.e., 380 nm to 780 nm). In other embodiments, the device light may also have a wavelength selected from the UV wavelength range. In yet other embodiments, the device light may also have a wavelength selected from the IR wavelength range. However, in particular, the device light has a spectral power of at least 80%, such as at least 90%, in the visible wavelength range.

[0010] In an operating mode of the light generating system, device light can propagate through the system. In particular, in various embodiments, at least a portion of the device light can propagate to a luminescence conversion arrangement, and at least a portion of the device light can propagate to a diffuser arrangement. Note that in various embodiments, the term "luminescence conversion arrangement" can refer to one or more luminescence conversion arrangements. Further, note that the term "diffuser arrangement" can refer to one or more diffuser arrangements.

[0011] At least a portion of the device light that can propagate to the luminescent conversion arrangement can be converted into luminescent material light. Therefore, in various embodiments, the luminescent conversion arrangement may include a luminescent material. In particular, the luminescent material can be configured to convert at least a portion of the device light incident on the luminescent material into luminescent material light. Herein, the luminescent material light can in particular have a wavelength different from the device light, for example, the luminescent material light can have a wavelength in the yellow wavelength range, while the device light can have a wavelength in the blue wavelength range. Furthermore, in various embodiments, the luminescent material can in particular be configured in a reflective mode relative to the device light illuminating the luminescent material. In particular, in various embodiments, the luminescent material can be configured in a reflective mode relative to the device light illuminating the luminescent material. Therefore, in various embodiments, the luminescent conversion arrangement can be configured to provide luminescent material light.

[0012] Herein, when an element is indicated as operating in a transmissive mode, in embodiments this may imply that at one or more wavelengths, the portion of radiation that is transmitted may be greater than the portion of radiation that is reflected or absorbed. Herein, when an element is indicated as operating in a reflective mode, this may imply in embodiments that at one or more wavelengths, the portion of radiation that is reflected may be greater than the portion of radiation that is transmitted or absorbed.

[0013] Note that when the light-emitting material is damaged or worn, the device light still does not escape directly from the system, which may aid safety.

[0014] In various embodiments, at least a portion of the device light that may propagate to the diffuser arrangement may specifically include polarized light having one of a first polarization and a second polarization. This polarization may be present due to the properties of the light source or may be imposed by a polarization optical element. The polarized light may, for example, have p-polarization or s-polarization, as also described below. In various embodiments, the polarization of the device light may be controllable.

[0015] Furthermore, in various embodiments, the diffuser arrangement may be configured to generate diffused device light from at least a portion of the device light received by the diffuser arrangement. Thus, in order to do so, the diffuser arrangement may include at least a quarter wave plate, a polarization-maintaining diffuser, and a specular (metal) reflector.

[0016] Furthermore, a polarizing beam splitter may be applied. In various embodiments, the polarizing beam splitter may be considered to be included by the diffuser arrangement, and in other embodiments, may be considered to be arranged between one or more light generating devices and the diffuser arrangement. In particular, the polarizing beam splitter may be arranged between one or more light generating devices and a quarter wave plate.

[0017] In various embodiments, a polarization beam splitter may be configured downstream of one or more light generating devices. Thus, a polarization beam splitter may be configured in a light receiving device having one or more light generating devices. In particular, the polarization beam splitter may be transmissive to one of light having a first polarization and light having a second polarization. Additionally or alternatively, the polarization beam splitter may be reflective to the other of the light having the first polarization and the light having the second polarization. Thus, for example, in various embodiments, the polarization beam splitter may be transmissive to light having p-polarization and reflective to light having s-polarization. Polarization beam splitters are further discussed below in various embodiments.

[0018] In other embodiments, a quarter-wave plate can be disposed between the polarization beam splitter and the polarization-maintaining diffuser. Thus, the quarter-wave plate can be configured to be in a light-receiving relationship with the polarized light transmitted by the polarization beam splitter. Quarter-wave plates are further discussed below in other embodiments.

[0019] In yet other embodiments, a polarization-maintaining diffuser (or "diffuser") can be configured between a quarter-wave plate and a specular metal reflector. Thus, the polarization-maintaining diffuser can be configured to be in light-receiving relationship with polarized light emitted from the quarter-wave plate. In particular, in various embodiments, the polarization-maintaining diffuser can be configured to diffuse device light, in particular, device light having a polarization imposed on the device light by the quarter-wave plate (see also below). More particularly, the polarization-maintaining diffuser can be configured to (substantially) maintain the polarization of device light incident on the polarization-maintaining diffuser. Thus, in various embodiments, the polarization-maintaining diffuser can generate diffused device light having maintained polarization. In particular, the polarization-maintaining diffuser is transmissive to the device light. Thus, the device light can be transmitted and diffused (in particular, while substantially maintaining polarization).

[0020] In various embodiments, the diffuser light is transmitted through a polarization-maintaining diffuser, such that the diffuser light is substantially perpendicularly incident on the reflector. Consequently, the reflector can specularly reflect at least a portion of the diffuser light, and more particularly, can reflect substantially all of the diffuser light received by the reflector. That is, the reflector can be reflective of the diffuser light. The reflected diffuser light can propagate back to the wave plate. The term "reflector" can also be used instead of the term "reflector."

[0021] In various embodiments, the reflector may in particular comprise a metal reflector. In various embodiments, the metal reflector may comprise a material having at least 80% reflectivity (such as at least 85%, such as at least 90%, including at least 92%, such as at least 95% reflectivity) for the wavelength of light to be reflected (e.g., light in the blue wavelength range or in the red wavelength range). In various embodiments, the reflector may consist essentially of a metal material. In other embodiments, the reflector may comprise a layer comprising a metal material (e.g., evaporated onto a substrate by physical vapor deposition (PVD)). The metal layer may also be protected, for example, by being covered by a transparent layer, such as a metal oxide layer (e.g., aluminum oxide). Thus, in particular, in various embodiments, the reflector may comprise one or more materials selected from the group consisting of aluminum, gold, copper, and silver. Thus, the reflector may comprise a metal reflector configured to reflect diffuser light received by the reflector such that the polarization of the incident diffuser light is reversed.

[0022] In various embodiments, the quarter-wave plate can be configured to convert diffused device light into diffused device light having a second polarization. Further, the polarizing beam splitter can be configured in a light-receiving relationship with the quarter-wave plate such that the diffused device light having the second polarization (imposed by the quarter-wave plate) can be reflected by the polarizing beam splitter.

[0023] Furthermore, in various embodiments, one or more secondary optical elements may be configured to collimate the device light. More particularly, one of the following may apply: (i) a primary secondary optical element may be configured between at least one of the one or more light-generating devices and the luminescent material, and (ii) a secondary optical element may be configured between the quarter-wave plate and the diffuser.

[0024] In various embodiments, the one or more secondary optical elements may be one or more secondary lenses. In particular, the lenses may be configured to collimate, and thus focus, the device light. In various embodiments, a primary secondary optical element, such as a primary secondary lens, may be configured in the luminescence conversion arrangement. In particular, the primary secondary optical element may be configured between at least one of the one or more light-generating devices and the luminescent material. In this configuration, the primary secondary optical element may specifically collimate the device light into a spot on the luminescent material.

[0025] In other embodiments, the primary secondary optical element (e.g., a primary secondary lens) can be configured in a diffuser arrangement. In particular, the secondary optical element can be configured between the wave plate and the diffuser. In this configuration, the secondary optical element can specifically collimate the device light into a spot on the diffuser.

[0026] In yet other embodiments, the light generating system may include a primary second optical element and a secondary second optical element as described above.

[0027] The efficiency of a diffuser arrangement can be improved by using the secondary optical element described herein to focus the device light into a spot on the luminescent material and the diffuser. In short, the secondary optical element can: (i) help promote similarity between the luminescent material beam and the diffused device beam, and (ii) help ensure that the diffused device light is perpendicularly incident on the reflector.

[0028] Therefore, in specific embodiments, the device light spot on the luminescent material and the device light spot on the diffuser can have substantially the same area. In particular, these areas can be small, i.e., the equivalent circular diameter of these areas can be ≤ 2 mm, such as ≤ 1 mm. The equivalent circular diameter can be defined as perpendicular to the optical axis of the device light propagating to the luminaire. In particular, the equivalent circular diameter can be at least 10 μm, such as at least 50 μm, for example, at least 0.1 mm. More particularly, the equivalent circular diameter of the device light spot can be at most 2 mm, such as at most 1 mm, for example, at most 0.5 mm.

[0029] Therefore, in particular, in various embodiments, a non-zero distance may exist between the quarter-wave plate and the polarization-maintaining diffuser. Furthermore, in various embodiments, a non-zero distance may exist between the polarization-maintaining diffuser and the reflector. In particular, the non-zero distance may be at least 0.1 mm, particularly at least 1 mm or at least 5 mm, such as 10 mm. Furthermore, the non-zero distance may be at most 10 cm or at most 15 cm, such as 20 cm.

[0030] A polarization-maintaining diffuser can diffuse at least a portion of the device light. Therefore, the polarization-maintaining diffuser can not only transmit the light but also scatter it. Therefore, the polarization-maintaining diffuser is a diffuser.

[0031] Therefore, in various embodiments, the light generating system may be configured to generate system light. In particular, in an operating mode of the light generating system, the system light may include diffused device light (reflected by the polarization beam splitter) and luminescent material light (generated in the luminescent material).

[0032] Some other embodiments related to light generating devices are described herein below.

[0033] As indicated above, the light generating system includes a light generating device. In particular, the light generating device can be configured to generate device light. In particular, the light generating device can include a light source. In various embodiments, the light generating device can include a solid-state light source. In particular, in various embodiments, the light generating device can include a laser. In particular, in other embodiments, the light generating device can include a superluminescent diode. In particular, the light source can be configured to generate light source light. In various embodiments, the device light can essentially consist of light source light. The term "light generating device" can also refer to a plurality of light generating devices that can provide device light with substantially the same spectral power distribution. In a specific embodiment, the term "light generating device" can also refer to a plurality of light generating devices that can provide device light with different spectral power distributions.

[0034] The term "light source" can, in principle, refer to any light source known in the art. The light source can be a conventional (tungsten) bulb, a low-pressure mercury lamp, a high-pressure mercury lamp, a fluorescent lamp, or an LED (light-emitting diode). In specific embodiments, the light source comprises a solid-state LED light source (such as an LED or a laser diode (or "diode laser")). The term "light source" can also refer 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 a so-called chip-on-board (COB) light source in various embodiments. The term "COB" particularly refers to an LED chip in the form of a semiconductor chip that is neither enclosed nor connected, but is directly mounted on a substrate such as a PCB. Therefore, multiple light-emitting semiconductor light sources can be configured on the same substrate. In various embodiments, a COB is a plurality of LED chips configured together as a single lighting module. The light source can have a light escape surface. With reference to conventional light sources such as light bulbs or fluorescent lamps, the light escape surface can be the outer surface of a glass or quartz envelope. For example, in the case of an LED, the light exit surface can be the LED die, or, when a resin is applied to the LED die, the light exit surface can be the outer surface of the resin. In principle, the light exit surface can also be the terminal end of an optical fiber. The term exit surface particularly relates to the portion of the light source from which light actually leaves or escapes. The light source is configured to provide a light beam. The light beam (therefore) escapes from the light exit surface of the light source.

[0035] Likewise, the light generating device may comprise a light escape surface, such as an end window. Further, likewise, the light generating system may comprise a light escape surface, such as an end window.

[0036] The term "light source" may refer to a semiconductor light emitting device, such as a light emitting diode (LED), a resonant cavity light emitting diode (RCLED), a vertical cavity laser diode (VCSEL), an edge emitting laser, etc. The term "light source" may also refer to an organic light emitting diode (OLED), such as a passive matrix organic light emitting diode (PMOLED) or an active matrix organic light emitting diode (AMOLED). In a specific embodiment, the light source includes a solid-state light source (such as an LED or a laser diode). In one embodiment, the light source includes an LED (light emitting diode). The term "light source" or "solid-state light source" may also refer to a superluminescent diode (SLED).

[0037] The term LED may also refer to a plurality of LEDs.

[0038] The term "light source" may also relate to a plurality of (substantially identical (or different)) light sources, such as 2 to 2000 solid-state light sources. In various embodiments, the light source may comprise one or more micro-optical elements (micro-lens arrays) located downstream of a single solid-state light source (such as an LED) or downstream of a plurality of solid-state light sources (i.e., shared by a plurality of LEDs, for example). In various embodiments, the light source may comprise an LED with on-chip optics. In various embodiments, the light source comprises a single LED (with or without optics) that is pixelated (in various embodiments, on-chip beam steering is provided).

[0039] In various embodiments, the light source can be configured to provide primary radiation that is used as, for example, a blue light source (e.g., a blue LED), or a green light source (e.g., a green LED), and a red light source (e.g., a red LED). Such LEDs, which may not include a luminescent material ("phosphor"), may be indicated as direct color LEDs.

[0040] However, in other embodiments, the light source can be configured to provide primary radiation, and a portion of the primary radiation is converted into secondary radiation. The secondary radiation can be based on a conversion performed by a luminescent material. Therefore, the secondary radiation can also be indicated as luminescent material radiation. In various embodiments, the luminescent material can be included by the light source (such as an LED having a luminescent material layer or a dome including a luminescent material). Such an LED can be indicated as a phosphor-converted LED or a PC LED (phosphor-converted LED). In other embodiments, the luminescent material can be configured at a certain distance ("remote") from the light source (such as an LED having a luminescent material layer that is not in physical contact with the die of the LED). Therefore, in a specific embodiment, the light source can be a light source that emits at least light of a wavelength selected from the range of 380nm to 470nm during operation. However, other wavelengths are also possible. This light can be used in part by the luminescent material.

[0041] In various embodiments, the light generating device may include a luminescent material. In various embodiments, the light generating device may include a PC LED. In other embodiments, the light generating device may include a direct LED (i.e., without a phosphor). In various embodiments, the light generating device may include a laser device, such as a laser diode. In various embodiments, the light generating device may include a superluminescent diode. Thus, in specific embodiments, the light source may be selected from the group consisting of a laser diode and a superluminescent diode. In other embodiments, the light source may include an LED.

[0042] The light source may specifically be configured to generate a source light having an optical axis (O), (beam shape) and a spectral power distribution. In various embodiments, the source light may comprise one or more bands having a bandwidth known to the laser.

[0043] The term "light source" may (thus) refer to a light-generating element (such as, for example, a solid-state light source) or, for example, to a package of a light-generating element (such as a solid-state light source), and one or more of an element containing luminescent material and (other) optical devices (such as lenses, collimators). A light converter element ("converter element" or "converter") may include an element containing luminescent material. For example, a solid-state light source such as a blue LED is a light source. A combination of a solid-state light source (which serves as a light-generating element) and a light converter element (such as a blue LED and a light converter element optically coupled to the solid-state light source) may also be a light source (but may also be indicated as a light-generating device). Thus, a white LED is a light source (but may also be indicated as a (white) light-generating device, for example).

[0044] The term "light source" herein may also refer to light sources including solid state light sources, such as LEDs or laser diodes or super luminescent diodes.

[0045] In various embodiments, the term "light source" may (therefore) also refer to a light source that is (also) based on the conversion of light, such as a light source in combination with a luminescent converter material. Thus, the term "light source" may also refer to a combination of an LED and a luminescent material configured to convert at least a portion of the LED radiation, or to a combination of a (diode) laser and a luminescent material configured to convert at least a portion of the (diode) laser radiation.

[0046] In various embodiments, the term "light source" may also refer to a combination of a light source (e.g., an LED) and a filter that can modify the spectral power distribution of light generated by the light source. In particular, the term "light generating device" may be used to address the light source and other (optical components) such as filters and / or beam shaping elements.

[0047] In various embodiments, the phrases "different light sources" or "plurality of different light sources" and similar phrases may refer to multiple solid-state light sources selected from at least two different bins. Similarly, in various embodiments, the phrases "identical light source" or "plurality of the same light sources" and similar phrases may refer to multiple solid-state light sources selected from the same bin.

[0048] The terms "solid-state light source" or "solid-state material light source" and similar terms may particularly refer to semiconductor light sources, such as light emitting diodes (LEDs), diode lasers or superluminescent diodes.

[0049] The term "laser source" particularly refers to a laser. Such a laser can particularly be configured to generate device light having one or more wavelengths of UV light, visible light, or infrared light (particularly having a wavelength selected from the spectral wavelength range of 200 nm to 2000 nm, such as 300 nm to 1500 nm). The term "laser" particularly refers to a device that emits light through an optical amplification process based on stimulated emission of electromagnetic radiation.

[0050] In particular, in various embodiments, the term "laser" may refer to a solid-state laser. In specific embodiments, the term "laser" or "laser source" or similar terms refers to a laser diode (or diode laser).

[0051] Thus, in various embodiments, the light source comprises a laser source. In various embodiments, the term "laser" or "solid-state laser" or "solid-state material laser" may refer to one or more of the following: cerium-doped lithium strontium (or calcium) aluminum fluoride (Ce:LiSAF, Ce:LiCAF), chromium-doped chrysoberyl (alexandrite) laser, chromium ZnSe (Cr:ZnSe) laser, divalent samarium-doped calcium fluoride (Sm:CaF2) laser, Er:YAG laser, erbium-doped and co-doped Erbium-ytterbium glass lasers, F-center lasers, holmium YAG (Ho:YAG) lasers, Nd:YAG lasers, NdCrYAG lasers, neodymium-doped yttrium calcium oxyborate Nd:Yca4O(BO3)3 or Nd:YCOB, neodymium-doped yttrium orthovanadate (Nd:YVO4) lasers, neodymium glass (Nd:glass) lasers, neodymium YLF (Nd:YLF) solid-state lasers, promethium-147-doped phosphate glass (147Pm 3+ : glass) solid-state lasers, ruby ​​lasers (Al2O3:Cr 3+ ), Thulium YAG (Tm:YAG) laser, Titanium Sapphire (Ti: Sapphire; Al2O3:Ti 3+ ) lasers, calcium fluoride doped with trivalent uranium (U:CaF2) solid-state lasers, ytterbium-doped glass lasers (rods, plates / chips and optical fibers), ytterbium YAG (Yb:YAG) lasers, Yb2O3 (glass or ceramic) lasers, etc.

[0052] For example, including second harmonic and third harmonic generation embodiments, the light source may include one or more of the following: a F-centered laser, a Yttrium orthovanadate (Nd:YVO4) laser, a Promethium-147-doped phosphate glass (147Pm 3+ : glass) and titanium sapphire (Ti: sapphire; Al2O3:Ti 3+ ) lasers. For example, this light source can be used to generate blue light by taking into account second-harmonic and third-harmonic generation.

[0053] In various embodiments, the terms "laser", "solid-state laser" or "solid-state material laser" may refer to one or more 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.

[0054] Lasers can be combined with upconverters to achieve shorter wavelengths. For example, upconversion can be achieved by using some (trivalent) rare earth ions, or by using nonlinear crystals. Alternatively, lasers can be combined with downconverters (such as dye lasers) to achieve longer wavelengths.

[0055] As can be derived below, the term "laser source" may also refer to a plurality of (different or identical) laser sources. In a specific embodiment, the term "laser source" may refer to a plurality of (N) (identical) laser sources. In various embodiments, N=2 or more. In a specific embodiment, N may be at least 5, such as in particular at least 8. In this way, a higher brightness can be obtained. In various embodiments, the laser sources may be arranged in a laser bank (see also above). In various embodiments, the laser bank may include heat dissipation and / or optical devices, for example, lenses for collimating the laser. Therefore, in various embodiments, the lasers in a laser bank (or "laser array group") may share the same optical devices.

[0056] The laser source is configured to generate laser source light (or "laser light"). The source light may essentially consist of laser source light. The source light may also include laser source light from two or more (different or identical) laser sources. For example, the laser source light from two or more (different or identical) laser sources may be coupled into a light guide to provide a single light beam comprising the laser source light from the two or more (different or identical) laser sources. In a specific embodiment, the source light is therefore particularly collimated source light. In a further embodiment, the source light is particularly (collimated) laser source light.

[0057] In various embodiments, the laser source light may include one or more bands having a known bandwidth for the laser. In a specific embodiment, the band(s) may be relatively sharp lines, such as having a full width at half maximum (FWHM) within a range of less than 20 nm (such as equal to or less than 10 nm) at RT. Thus, the source light may have a spectral power distribution (intensity that varies with wavelength on an energy scale) that may include one or more (narrow) bands.

[0058] The beam (of the light source light) may be a focused or collimated beam of the (laser) light source light. The term "focusing" may particularly refer to converging to a small spot. This small spot may be located at the discrete converter region, or (slightly) upstream or (slightly) downstream thereof. In particular, the focusing and / or collimation may be such that the cross-sectional shape (perpendicular to the optical axis) of the beam at (laterally to) the discrete converter region is not substantially larger than the cross-sectional shape (perpendicular to the optical axis) of the discrete converter region (where the light source light illuminates the discrete converter region). Focusing may be performed using one or more optical devices, such as (focusing) lenses. In particular, two lenses may be used to focus the laser light. Collimation may be performed using one or more (other) optical devices, such as collimating elements, such as lenses and / or parabolic mirrors. In various embodiments, the (laser) light source beam may be relatively highly collimated, such as, in various embodiments, ≤2° (FWHM), more particularly ≤1° (FWHM), and most particularly ≤0.5° (FWHM). Hence, ≤ 2° (FWHM) can be considered as (highly) collimated source light. Optics can be used to provide (high) collimation (see also above).

[0059] The term "solid-state material laser" and similar terms may refer to solid-state lasers based on crystals or glasses doped with ions (such as transition metal ions and / or lanthanide ions), fiber lasers, photonic crystal lasers, semiconductor lasers (such as, for example, vertical cavity surface emitting lasers (VCSELs)), etc.

[0060] The term "solid-state light source" and similar terms may particularly refer to semiconductor light sources, such as light-emitting diodes (LEDs), diode lasers, or superluminescent diodes. The term "semiconductor-based light source" may also be used instead of the term "solid-state light source." Thus, the term "semiconductor-based light source" may, for example, refer to one or more of the following: a light-emitting diode (LED), a diode laser, and a superluminescent diode. Thus, a light-generating device may include one or more of the following: a light-emitting diode (LED), a diode laser, and a superluminescent diode.

[0061] Superluminescent diodes are known in the art. A superluminescent diode may be indicated as a semiconductor device that may be capable of emitting a broad spectrum of low-coherence light like an LED, while having a brightness on the order of a laser diode.

[0062] The beam (of the light source) can be a focused or collimated beam of (laser) light source light. The term "focusing" can particularly refer to converging to a small spot. This small spot can be located at the discrete converter region, or (slightly) upstream or (slightly) downstream thereof. In particular, the focusing and / or collimation can be such that the cross-sectional shape (perpendicular to the optical axis) of the beam at (laterally to) the discrete converter region is not substantially larger than the cross-sectional shape (perpendicular to the optical axis) of the discrete converter region (where the light source light illuminates the discrete converter region). Focusing can be performed using one or more optical devices, such as (focusing) lenses. In particular, two lenses can be used to focus the laser light source. Collimation can be performed using one or more (other) optical devices, such as collimating elements, such as lenses and / or parabolic mirrors. In various embodiments, the (laser) light source beam can be relatively highly collimated, such as, in various embodiments, ≤2° (FWHM), more particularly ≤1° (FWHM), and most particularly ≤0.5° (FWHM). Hence, ≤ 2° (FWHM) can be considered as (highly) collimated source light.Optical devices can be used to provide the (high) collimation (see also above).

[0063] The term "solid-state material laser" and similar terms may refer to solid-state lasers based on crystals or glasses doped with ions (such as transition metal ions and / or lanthanide ions), fiber lasers, photonic crystal lasers, semiconductor lasers (such as, for example, vertical cavity surface emitting lasers (VCSELs)), etc.

[0064] The term "solid-state light source" and similar terms may particularly refer to semiconductor light sources, such as light-emitting diodes (LEDs), diode lasers, or superluminescent diodes. The term "semiconductor-based light source" may also be used instead of the term "solid-state light source." Thus, the term "semiconductor-based light source" may, for example, refer to one or more of the following: a light-emitting diode (LED), a diode laser, and a superluminescent diode. Thus, a light-generating device may include one or more of the following: a light-emitting diode (LED), a diode laser, and a superluminescent diode.

[0065] Superluminescent diodes are known in the art. A superluminescent diode may be indicated as a semiconductor device that may be capable of emitting a broad spectrum of low-coherence light like an LED, while having a brightness on the order of a laser diode.

[0066] US2020192017 for example indicates that "with current technology a single SLED can emit with sufficient spectral flatness and sufficient output power in the wavelength range of 800 nm to 900 nm, for example over a bandwidth of at most 50 nm to 70 nm. In the visible range for display applications, i.e., in the wavelength range of 450 nm to 650 nm, a single SLED can emit with current technology over a bandwidth of at most 10 nm to 30 nm. These emission bandwidths are too small for display or projector applications requiring red (640 nm) emission, green (520 nm) emission and blue (450 nm) emission (i.e., RGB emission)". Further, in Chapter 9.3 Superluminescent Diodes by Szymon Stanczyk, Anna Kafar, Dario Schiavon, Stephen Najda, Thomas Slight, Piotr Perlin, (multiple) book editors Fabrizio Roccaforte, Mike Leszczynski https: / / doi.org / 10.1002 / 9783527825264.ch9Superluminescent diodes are described in “Edge Emitting Laser Diodes and Superluminescent Diodes”, first published on August 3, 2020. This book (and in particular, Chapter 9.3) is incorporated herein by reference. Among other things, a superluminescent diode (SLD) is an emitter that combines the features of a laser diode and a light emitting diode. SLD emitters utilize stimulated emission, which means that these devices operate at current densities similar to those of laser diodes. The main difference between LDs and SLDs is that in the latter case the device waveguide can be designed in a special way to prevent the formation of standing waves and lasing. Nevertheless, the presence of the waveguide also ensures the emission of a high-quality beam with high spatial coherence of the light, but the light is characterized by low temporal coherence at the same time" and "Currently, the most successful designs for nitride SLDs are bent, curved or tilted waveguide geometries and tilted facet geometries, while in all cases the front end of the waveguide intersects the device facets in an inclined manner, as shown in Figure 9.10. The tilted waveguide suppresses light reflections from the facets into the waveguide by directing the light outside the lossy, non-pumped region of the device chip. Thus, an SLD can be in particular a semiconductor light source in which the spontaneously emitted light is amplified by stimulated emission in the active region of the device. This emission is known as "superluminescence". Superluminescent diodes combine the high power and brightness of laser diodes with the low coherence of conventional light-emitting diodes. The low (temporal) coherence of the source has the advantage that speckle is significantly reduced or invisible, and the spectral distribution of the emission is much broader than that of laser diodes, which may be more suitable for lighting applications. In particular, the spectral power distribution of a superluminescent diode may vary with varying current. In this way, the spectral power distribution can be controlled, see also, for example, Abdullah A. Alatawi et al. in Optics Express, Vol. 26, No. 20, pp. 26355-26364, https: / / doi.org / 10.1364 / QE.26.026355 .

[0067] Thus, in various embodiments, the present invention can provide a laser phosphor-based stage lighting engine with a highly efficient polarization-maintaining diffuser arrangement (or "configuration").

[0068] As mentioned above, the diffuser arrangement may comprise a (specularly reflective metal) mirror. In various embodiments, the reflector may comprise a plane mirror. In particular, in such an embodiment, the diffuser arrangement may comprise a first optical element, which is arranged between the polarization-maintaining diffuser and the (plane) reflector. More particularly, the first optical element may be configured to collimate at least a portion of the light passing through the diffuser device into a beam perpendicular to the (plane) reflector. In various embodiments, the first optical element may be configured to collimate substantially all of the light passing through the diffuser device into a beam perpendicular to the (plane) reflector. In various embodiments, the first optical element may in particular comprise a lens. In particular, the first optical element may comprise one or more lenses. Therefore, in a specific embodiment, the reflector comprises a plane mirror, wherein the diffuser arrangement comprises the first optical element, wherein the first optical element is arranged between the polarization-maintaining diffuser and the reflector, wherein the first optical element is configured to collimate at least a portion of the light passing through the diffuser device into a beam perpendicular to the reflector, wherein the first optical element comprises a lens.

[0069] In other embodiments, the reflector may comprise a curved reflector. In particular, in various embodiments, the reflector may comprise a concave reflector. In such embodiments, at least a portion of the light passing through the diffuser may in particular be reflected vertically from the curved reflector. Therefore, the curved reflector may have a curved shape that is selected such that the light passing through the diffuser transmitted (and / or scattered) by the diffuser may be incident vertically on the reflector. For example, in various embodiments, the curved reflector may have a semicircular shape or a semi-elliptical shape. Taking into account the size, shape and distance relative to each other, a person skilled in the art will be able to select a combination of the diffuser and the curved reflector such that the light passing through the diffuser is incident vertically on the curved reflector.

[0070] Device light can include different polarizations while propagating through the system. This difference can be particularly exploited because a polarizing beam splitter can be configured to be transmissive to one of light having a first polarization and light having a second polarization, and reflective to the other of the first polarization and light having the second polarization.

[0071] In various embodiments, the first polarization and the second polarization may in particular comprise linear polarization. In particular, in various embodiments, the polarized light comprising the first polarization may in particular comprise one of p-polarization and s-polarization. Further, the polarized light comprising the second polarization may in particular comprise the other of p-polarization and s-polarization. Thus, in such embodiments, the first polarization and the second polarization may be completely opposite. In various embodiments, the first polarization and the second polarization may be (substantially) linear polarizations. For example, in various embodiments, the first polarization may comprise at least 80% p-polarized light, such as at least 90% p-polarized light, in particular 100% p-polarized light. Similarly, for example, the second polarization may comprise at least 80% s-polarized light, such as at least 90% s-polarized light, in particular 100% s-polarized light. In a specific embodiment, the polarized light comprising the first polarization comprises one of p-polarization and s-polarization, and the polarized light comprising the second polarization comprises the other of p-polarization and s-polarization.

[0072] For example, in a specific embodiment, the first polarization is p-polarization, and thus the second polarization is s-polarization. In other specific embodiments, the first polarization is s-polarization, and thus the second polarization is p-polarization.

[0073] Thus, in various embodiments, polarized light comprising a first polarization may have an opposite polarization to polarized light comprising a second polarization.

[0074] The polarization of the device light may be substantially unaffected by the diffuser. Therefore, the diffuser may be a polarization-maintaining diffuser. Therefore, in various embodiments, the polarization-maintaining diffuser may comprise an optically isotropic material. In particular, the polarization-maintaining diffuser may comprise a material selected from the group consisting of: cubic crystals, stress-free glass, and isotropic transparent polymers (such as silicone rubber, PMMA, etc.). Furthermore, the polarization-maintaining diffuser may comprise a surface relief, i.e., the surface of the polarization-maintaining diffuser may comprise a (pseudo-random) microstructure of depressions and protrusions.

[0075] As used herein, the term "optically isotropic material" may refer to a material whose optical properties (i.e., refractive index) are the same in all directions. Thus, in various embodiments, the refractive index of light incident on a polarization-maintaining diffuser may be independent of the polarization of the light, i.e., the polarization-maintaining diffuser may be non-birefringent.

[0076] More specifically, the diffuser can maintain the polarization of light incident on the diffuser. For example, in embodiments where RHC polarized light is incident on the diffuser, the diffuser can emit RHC polarized diffused light. Obviously, in embodiments where the light has another polarization (such as linearly polarized LHC polarization), other polarizations can also be maintained.

[0077] Furthermore, the polarization of the (diffused) device light may be affected by a wave plate included by the diffuser arrangement. In particular, in various embodiments, the wave plate may include a quarter wave plate. More particularly, the wave plate may be configured to convert device light having a first polarization into device light having a (first) circular polarization. Further, the wave plate may be configured to convert diffused device light having a (second) circular polarization into diffused device light having a second polarization. Thus, in specific embodiments, the quarter wave plate is configured to convert device light having a first polarization into device light having a circular polarization, and to convert diffused device light having a circular polarization into diffused device light having a second polarization.

[0078] Wave plates are known in the art. In particular, the wave plates herein may comprise a birefringent material. More particularly, the wave plates may comprise a material selected from the group consisting of (crystalline) quartz, mica, calcite, and plastic.

[0079] As is known in the art, a wave plate or retarder is an optical device that changes the polarization state of a light wave traveling through it. A quarter-wave plate can convert linearly polarized light into circularly polarized light (or vice versa). Thus, a quarter-wave plate can be configured to phase shift the device light, in particular, to produce a λ / 4 phase shift of the device light.

[0080] In a specific embodiment, the wave plate can be configured to convert device light having linear p-polarization into circularly polarized light (i.e., right-handed (RHC) circularly polarized light or left-handed (LHC) circularly polarized light). Further, the wave plate can be configured to convert device light having linear s-polarization into circularly polarized light (i.e., right-handed (RHC) circularly polarized light or left-handed (LHC) circularly polarized light). Still further, the wave plate can be configured to convert diffused device light having LHC polarization into linearly polarized light (i.e., p-polarized light or s-polarized light). Still further, the wave plate can be configured to convert diffused device light having RHC polarization into linearly polarized light (i.e., p-polarized light or s-polarized light). Thus, the light generating system can include a wave plate for manipulating the device light. Still further, the light generating system can (also) include a dichroic reflector for manipulating the device light.

[0081] As described above, the specularly reflective metal mirror can reverse the polarization of light passing through the diffuser. In particular, a first type of circularly polarized light can be converted into a second type of reflected circularly polarized light. The first and second types can be selected from left-handed circularly polarized light and right-handed circularly polarized light. See also below.

[0082] Thus, in each embodiment, one of the following may apply: (i) the polarization beam splitter may be configured to transmit device light having a first linear polarization; the quarter wave plate may be configured to convert the transmitted device light having the first linear polarization into a first circularly polarized light having a first chirality; the specularly reflective metal mirror may be configured to reflect the first circularly polarized light having the first chirality into a second circularly polarized light having a second chirality; the quarter wave plate may be configured to convert the second circularly polarized light having the second chirality into a device light having a second linear polarization, wherein the device light having the second linear polarization is rotated 90° relative to the device light having the first linear polarization; the polarization beam splitter may be configured to reflect the device light having the first linear polarization into a second circularly polarized light having a second chirality; (ii) the polarization beam splitter can be configured to reflect the device light having the first linear polarization; the quarter wave plate can be configured to convert the reflected device light having the first linear polarization into a first circularly polarized light having a first chirality; the mirror-reflecting metal mirror can be configured to reflect the first circularly polarized light having the first chirality into a second circularly polarized light having a second chirality; the quarter wave plate can be configured to convert the second circularly polarized light having the second chirality into a device light having a second linear polarization, wherein the device light having the second linear polarization is rotated 90° relative to the device light having the first linear polarization; and the polarization beam splitter can be configured to transmit the device light having the second linear polarization.

[0083] Furthermore, a dichroic reflector may be applied. In various embodiments, the dichroic reflector may be considered to be included by the luminescence conversion arrangement, and in other embodiments may be considered to be arranged between one or more light generating devices and the luminescence conversion arrangement. In particular, the dichroic reflector may be arranged between one or more light generating devices and the luminescent material. Furthermore, in various embodiments, the primary second optical element (as described above) may be arranged between the dichroic reflector and the luminescent material.

[0084] Thus, in various embodiments, the luminescence conversion arrangement may include a dichroic reflector (or "dichroic component") configured downstream of one or more of the one or more light generating devices. In particular, the dichroic reflector may be configured to transmit (or reflect) device light and reflect (or transmit) luminescent material light. Thus, in specific embodiments, the luminescence conversion arrangement further includes a dichroic reflector configured downstream of one or more of the light generating devices, wherein the dichroic reflector is configured to transmit device light and reflect luminescent material light.

[0085] In particular, the dichroic component can be configured to be in a light receiving relationship with one or more of the one or more light generating devices and the luminescent material, i.e., the dichroic component can be configured to receive at least a portion of the (blue) device light and at least a portion of the luminescent material light. The dichroic component can in particular perform controllable wavelength-related modifications to the light provided to the dichroic component. For example, in various embodiments, the dichroic component can be configured to transmit light in the blue wavelength range and reflect light in the yellow wavelength range. In specific embodiments, the dichroic component can be configured to transmit device light (wavelength in the blue wavelength range) and reflect luminescent material light (wavelength in the yellow-orange wavelength range). However, in other specific embodiments, the dichroic component can be configured to reflect device light (wavelength in the blue wavelength range) and transmit luminescent material light (wavelength in the yellow-orange wavelength range).

[0086] The terms "upstream" and "downstream" relate to the arrangement of items or features relative to the propagation of light from a light generating member (here in particular, a light source), wherein, relative to a first position within a light beam from the light generating member, a second position in the light beam that is closer to the light generating member is "upstream" and a third position within the light beam that is further away from the light generating member is "downstream".

[0087] As mentioned above, the light generating system may comprise one or more light generating devices configured to provide device light to the luminescent conversion arrangement and the diffuser arrangement.Thus, in various embodiments, the light generating system may comprise a plurality of light generating devices.

[0088] In various embodiments, the one or more light generating devices may include a first light generating device and a second light generating device. In particular, the first light generating device may be configured to generate a first device light, and the second light generating device may be configured to generate a second device light. Further, in various embodiments, the luminescent conversion arrangement may be configured in a light receiving arrangement having the first light generating device. Still further, in various embodiments, the diffuser arrangement may be configured in a light receiving arrangement having the second light generating device. Still further, in various embodiments, the light generating system may include a control system configured to control the first light generating device and the second light generating device. Therefore, in a specific embodiment, the one or more light generating devices include a first light generating device and a second light generating device, wherein the first light generating device is configured to generate a first device light, wherein the second light generating device is configured to generate a second device light, wherein the luminescent conversion arrangement is configured to be in a light receiving relationship with the first light generating device, and wherein the diffuser arrangement is configured to be in a light receiving relationship with the second light generating device.

[0089] In such an embodiment, the luminescent material may be specifically configured to convert at least a portion of the first device light received by the luminescent material into luminescent material light. Furthermore, in such an embodiment, the diffuser arrangement may be specifically configured to generate diffused device light from at least a portion of the second device light received by the diffuser arrangement. Therefore, in such an embodiment, the diffused device light may also be indicated as "diffused second device light."

[0090] In various embodiments, the light generating system may include one or more first light generating devices. Thus, the one or more first light generating devices may be configured to generate first device light. In various embodiments, the one or more first light generating devices may specifically include one or more first lasers. More specifically, in various embodiments, the one or more first light generating devices may include one or more first lasers in a laser group. In other embodiments, the one or more first light generating devices may include one or more first superluminescent diodes.

[0091] Furthermore, the one or more first light generating devices may be specifically configured to provide the first device light to the luminescence conversion arrangement. Thus, in various embodiments, the luminescence conversion arrangement may be configured to be in a light-receiving relationship with the one or more first light generating devices. In particular, the dichroic reflector may be configured to be in a light-receiving relationship with the one or more first light generating devices.

[0092] Similarly, in various embodiments, the light generating system may include one or more second light generating devices. In particular, in various embodiments, the one or more second light generating devices may include one or more second lasers in a laser group. Thus, the one or more second light generating devices may be configured to generate second device light. In various embodiments, the one or more second light generating devices may specifically include one or more second lasers. More particularly, in various embodiments, the one or more second light generating devices may include one or more second lasers in a laser group. In other embodiments, the one or more second light generating devices may include one or more second superluminescent diodes.

[0093] Furthermore, the one or more second light generating devices may be specifically configured to provide the second device light to the diffuser arrangement. Thus, in various embodiments, the diffuser arrangement may be configured in a light-receiving arrangement with the one or more second light generating devices. In particular, the polarizing beam splitter may be configured in a light-receiving relationship with the one or more second light generating devices.

[0094] In the embodiments described above, the first device light and the second device light can be light in the blue wavelength range in particular. Such a system (which uses separate (blue) light generating devices to provide light to the luminescent conversion arrangement and to the diffuser arrangement) can be beneficial because it can achieve tunability of light specifically tailored to the target arrangement. In particular, one or more first light generating devices can be configured so that the first device light can have an optimized brightness for improving the luminescent output of the luminescent material light portion of the system light. Additionally or alternatively, one or more second light generating devices can be configured so that the second device light can have an optimized blue point for improving the spectral power distribution of the system light.

[0095] To enable such optimization, a control system may be required. Thus, the system may include a control system or may be functionally coupled to a control system. The control system may be specifically configured to control the light generating system. For example, the control system may control the light generating system based on sensor signals, a time scheme (or timer), or user input (signal).

[0096] The term "control" and similar terms particularly refer to at least determining an action or supervising the operation of an element. Thus, as used herein, "control" and similar terms may, for example, refer to imposing an action on an element (determining an action or supervising the operation of an element), such as, for example, measuring, displaying, actuating, opening, shifting, changing temperature, etc. In addition, the term "control" and similar terms may also include monitoring. Thus, the term "control" and similar terms may include imposing an action on an element as well as imposing an action on an element and monitoring the element. Control of an element may be accomplished using 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. The element may include a control system. In various embodiments, the control system and the element may not be physically coupled. Control may be accomplished via wired and / or wireless control. The term "control system" may also refer to multiple different control systems, which may be functionally coupled, and for example, one control system may be a master control system, while one or more other control systems may be slave control systems. The control system may include or may be functionally coupled to a user interface.

[0097] The control system can also be configured to receive and execute instructions from a remote control. In various embodiments, the control system can be controlled via an application on a device (such as a portable device, such as a smartphone or iPhone, a tablet computer, etc.). Thus, the device does not have to be coupled to the lighting system, but can be (temporarily) functionally coupled to the lighting system.

[0098] Thus, in various embodiments, the control system can (also) be configured to be controlled by an application on a remote device. In such embodiments, the control system of the lighting system can be controlled from a control system or in slave mode. For example, a code (particularly a unique code for each lighting system) can be used to identify the lighting system. The control system of the lighting system can be configured to be controlled by an external control system that accesses the lighting system based on knowledge of the (unique) code (input via a user interface with an optical sensor (e.g., a QR code reader)). The lighting system can also include means for communicating with other systems or devices, such as using Bluetooth, Thread, WiFi, LiFi, ZigBee, BLE, WiMAX, or another wireless technology.

[0099] A system, device or apparatus may perform an action in a "mode" or "operation mode" or "mode of operation" or "operation mode". The term "operation mode" may also be indicated as a "control mode". Similarly, in a method, actions, or phases, or steps may be performed in a "mode" or "operation mode" or "mode of operation" or "operation mode". This does not exclude that the system or device or apparatus may also be applied to provide another control mode or multiple other control modes. Similarly, this may not exclude that: before and / or after the execution of the mode, one or more other modes may be executed.

[0100] However, in various embodiments, a control system may be available that is adapted to provide at least a control mode. If other modes are available, the selection of such a mode may in particular be performed via a user interface, although other options (such as executing a mode according to a sensor signal or a (time) schedule) may also be possible. In various embodiments, an operating mode may also refer to a system or device or apparatus that can only operate in a single operating mode (i.e., "on," without other tunability).

[0101] Therefore, in various embodiments, the control system may be controlled according to one or more of an input signal from a user interface, a sensor signal (of a sensor), and a timer. The term "timer" may refer to a clock and / or a predetermined time scheme.

[0102] In a particular embodiment, the control system may be configured to control the first light generating device and the second light generating device.

[0103] As described above, the light generating system may include a first light generating device and a second light generating device. However, in other embodiments, the light generating system may also include only one (type of) light generating device. In such an embodiment, the light generating system may further include a beam splitter, which is configured downstream of the light generating device, in particular, upstream of both the luminescent conversion arrangement and the diffuser arrangement. In a specific embodiment, the beam splitter may be a polarization beam splitter included by the diffuser arrangement. In other embodiments, the beam splitter may be a semi-silvered mirror. The semi-silvered mirror may be configured to: (i) transmit at least a portion of the device light to the diffuser arrangement, and (ii) reflect at least another portion of the device light to a third optical element. In particular, the third optical element may be configured to reflect the device light so that the device light propagates to the luminescent material contained in the luminescent conversion arrangement. More particularly, the third optical element may be a reflector, such as a reflector or a dichroic reflector.

[0104] Thus, the beam splitter can be configured to direct at least a portion of the device light to the luminescence conversion arrangement and at least another portion of the device light to the diffuser arrangement. In particular, in various embodiments, the beam splitter can: (i) transmit light having a first polarization, and (ii) reflect light having a second polarization. In such embodiments, the beam splitter can direct light having the first polarization to the diffuser arrangement while directing light having the second polarization to the luminescence conversion arrangement.

[0105] Because the light generating system includes a luminescence conversion arrangement containing luminescent material, the light generating system may generate heat. This heat may, for example, negatively impact the performance of the luminescent material. Therefore, in various embodiments, the light generating system may include a rotatable device. In particular, the rotatable device may include one of the group consisting of a phosphor wheel and a phosphor rod. In particular, the rotatable device may be configured to support the luminescent material. More particularly, the rotatable device may be configured to support a ring of luminescent material.

[0106] Furthermore, in various embodiments, the rotatable device may include a thermally conductive material, i.e., may include a heat sink or may be capable of conducting heat to a heat sink. Thus, for example, the luminescent material disposed on the phosphor wheel may be disposed in thermal contact with the thermally conductive material. However, in embodiments without a phosphor wheel, the thermally conductive material may also be disposed in thermal contact with the luminescent material. For example, in various embodiments, the luminescent material may be disposed in physical contact with the thermally conductive material.

[0107] Embodiments of light generating systems that include such a rotatable device as described herein may be beneficial because the luminescent material may be rotated, thereby providing alternating illumination cycles and cooling cycles to various segments of the luminescent material.

[0108] In particular, the luminescent material is contained by a luminophore. The luminophore may be a layer, such as a self-supporting layer. The luminophore may also be a coating. The luminophore may also comprise a luminescent coating on a support, in particular a light-transmitting support in transmission mode or a reflective support in reflection mode. In particular, the luminophore may be substantially self-supporting. In various embodiments, the luminescent material may be provided as a luminophore, such as a luminescent single crystal, a luminescent glass or a luminescent ceramic body. Such a body may be indicated as a "converter body" or a "luminophore". In various embodiments, the luminophore may be a luminescent single crystal or a luminescent ceramic body. For example, in various embodiments, a garnet luminescent material containing cerium may be provided as a luminescent single crystal or as a luminescent ceramic body. In other embodiments, the luminophore may comprise a light-transmitting body in which the luminescent material is embedded. For example, the luminophore may comprise a glass body in which the luminescent material is embedded. Alternatively, the glass itself may be luminescent. In other embodiments, the luminophore may comprise a polymer body in which the luminescent material is embedded.

[0109] In particular, the luminaire can be configured in a reflective mode. In reflective mode, thermal management can be easier because a substantial portion of the luminescent material can be in thermal contact with a heat-conducting element (e.g., a heat sink or diffuser). In various embodiments, the luminaire can be configured on a rotatable device as described above. Thus, the luminaire can be formed from a phosphor wheel or phosphor rod.

[0110] The luminescent material may be provided as a luminophore. Thus, the system may comprise a luminophore comprising the luminescent material.

[0111] The term "luminescent material" particularly refers to a material that can convert a first radiation (in particular, one or more of UV radiation and blue radiation) into a second radiation. Generally speaking, the first radiation and the second radiation have different spectral power distributions. Therefore, the term "luminescent converter" or "converter" can also be used instead of the term "luminescent material". Generally speaking, the second radiation has a spectral power distribution at a larger wavelength than the first radiation, which is the case in so-called down-conversion. However, in specific embodiments, the second radiation has a spectral power distribution at a smaller wavelength than the first radiation, which is the case in so-called up-conversion.

[0112] In various embodiments, a "luminescent material" may particularly refer to a material that can convert radiation into, for example, visible light and / or infrared light. For example, in various embodiments, the luminescent material may be capable of converting one or more of UV radiation and blue radiation into visible light. In particular embodiments, the luminescent material may also be capable of converting radiation into infrared radiation (IR). Thus, upon excitation with radiation, the luminescent material emits radiation. Generally speaking, the luminescent material will be a down-converter, i.e., radiation of a smaller wavelength is converted into radiation with a larger wavelength (λ). ex <λ em), but in a specific embodiment the luminescent material may comprise an upconverter luminescent material, ie radiation of a larger wavelength is converted into radiation with a smaller wavelength (λ ex >λ em ).

[0113] In various embodiments, the term "luminescence" may refer to phosphorescence. In various embodiments, the term "luminescence" may also refer to fluorescence. The term "emission" may also be used instead of the term "luminescence." Thus, the terms "first radiation" and "second radiation" may refer to excitation radiation and emission (radiation), respectively. Similarly, the term "luminescent material" may refer to phosphorescence and / or fluorescence in various embodiments.

[0114] The term "luminescent material" may also refer to a variety of different luminescent materials. Examples of possible luminescent materials are provided below. Therefore, in specific embodiments, the term "luminescent material" may also refer to a luminescent material composition. The term "phosphor" may also be used instead of the term "luminescent material." These terms are known to those skilled in the art.

[0115] In various embodiments, the luminescent material is selected from garnets and nitrides, in particular, doped with trivalent cerium or divalent europium, respectively. The term "nitride" may also refer to nitrogen oxides or nitrogen silicates, etc. Alternatively or additionally, the luminescent material(s) may be selected from silicates, in particular, doped with divalent europium.

[0116] In a specific embodiment, the luminescent material comprises a type A3B5O 12 : Ce, wherein A in various 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 wherein B in various embodiments comprises one or more of Al, Ga, In and Sc. In particular, A may comprise one or more of Y, Gd and Lu, such as in particular, one or more of Y and Lu. In particular, B may comprise one or more of Al and Ga, more in particular, at least Al, such as substantially entirely Al. Thus, in particular, a suitable luminescent material is a garnet material containing cerium. An embodiment of garnet in particular comprises A3B5O 12Garnet, wherein A comprises at least yttrium or lutetium, and wherein B comprises at least aluminum. This garnet may be doped with cerium (Ce), praseodymium (Pr), or a combination of cerium and praseodymium; however, in particular, it is doped with Ce. In particular, B may comprise aluminum (Al); however, in addition to aluminum, B may also partially comprise gallium (Ga) and / or scandium (Sc) and / or indium (In), in particular up to about 20% B, more particularly up to about 10% B (i.e., the B ions essentially consist of 90 mol % or more of Al and 10 mol % or less of one or more of Ga, Sc, and In); B may in particular comprise up to about 10% gallium. In another variant, B and O may be at least partially substituted by Si and N. 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 are present in an amount specifically only up to about 20% of A. In a specific embodiment, the garnet luminescent material comprises (Y 1-x Lu x )3B5O 12 :Ce, wherein x is equal to or greater than 0 and equal to or less than 1. The term ":Ce" indicates that part of the metal ions in the luminescent material (ie, in garnet: part of the "A" ions) are replaced by Ce. For example, in (Y 1-x Lu x )3Al5O 12 In the case of Ce, a portion of Y and / or Lu is replaced by Ce. This is known to those skilled in the art. Ce will generally not replace A by more than 10%; generally, the Ce concentration will be in the range of 0.1% to 4%, particularly 0.1% to 2% (relative to A). Assuming 1% Ce and 10% Y, the completely correct chemical formula may be (Y 0.1 Lu 0.89 Ce 0.01 )3Al5O 12 As known to those skilled in the art, Ce in garnet is essentially or exclusively in a trivalent state. As known to those skilled in the art, Ce in garnet is essentially or exclusively in a trivalent state.

[0117] In various embodiments, the luminescent material (therefore) comprises A3B5O 12 , wherein in a specific embodiment up to 10% of the BO can be replaced by Si—N.

[0118] In a specific embodiment, the luminescent material includes (Y x1-x2-x3 A' x2 Ce x3 )3(Al y1-y2 B' y2 )5O 12, where x1 + x2 + x3 = 1, where x3 > 0, where 0 < x2 + x3 ≤ 0.2, where y1 + y2 = 1, where 0 ≤ y2 ≤ 0.2, where A' includes one or more elements selected from the group consisting of lanthanide elements, and where B' includes one or more elements selected from the group consisting of Ga, In, and Sc. In various embodiments, x3 is selected from the range of 0.001 to 0.1. In the present invention, particularly x1 > 0, such as > 0.2, e.g., at least 0.8. Garnets having Y can provide a suitable spectral power distribution.

[0119] In a specific embodiment, up to 10% of B-O can 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); in a specific embodiment, B-O can refer to Al-O. As indicated above, in a specific embodiment, x3 can be selected from the range of 0.001 to 0.04. Particularly, such a luminescent material can have a suitable spectral distribution (however, see below), have a relatively high efficiency, have a relatively high thermal stability, and allow a high CRI (optionally, in combination with the light of other light sources described herein). Thus, in a specific embodiment, A can be selected from the group consisting of Lu and Gd. Alternatively or additionally, B can include Ga. Thus, in various embodiments, the luminescent material includes (Y x1-x2-x3 (Lu,Gd) x2 Ce x3 )3(Al y1-y2 Ga y2 )5O 12 , where Lu and / or Gd can be available. Even more particularly, x3 is selected from the range of 0.001 to 0.1, where 0 < x2 + x3 ≤ 0.1, and where 0 ≤ y2 ≤ 0.1. Further, in a specific embodiment, up to 1% of B-O can be replaced by Si-N. Here, the percentage refers to the number of moles (as known in the art); also see, for example, EP3149108. In yet other specific embodiments, the luminescent material includes (Y x1-x3 Ce x3 )3Al5O 12 , where x1 + x3 = 1, and where 0 < x3 ≤ 0.2, such as 0.001 to 0.1.

[0120] In a specific embodiment, the light generating device can include only a luminescent material of the type selected from garnets containing cerium. In an even further specific embodiment, the light generating device includes a single type of luminescent material, such as (Y x1-x2-x3 A' x2 Ce x3 )3(Al y1-y2 B' y2 )5O12 Thus, in a specific embodiment, the light generating device includes a luminescent material, wherein at least 85 wt%, and even more particularly, at least about 90 wt%, such as even more particularly, at least about 95 wt% of the luminescent material comprises (Y x1-x2-x3 A' x2 Ce x3 )3(Al y1-y2 B' y2 )5O 12 . Here, A' comprises one or more elements selected from the group consisting of lanthanide elements, and B' comprises one or more elements selected from the group consisting of Ga, In, and Sc, where x1 + x2 + x3 = 1, where x3 > 0, where 0 < x2 + x3 ≤ 0.2, where y1 + y2 = 1, where 0 ≤ y2 ≤ 0.2. In particular, x3 is selected from the range of 0.001 to 0.1. Note that in each embodiment, x2 = 0. Alternatively or additionally, in each embodiment, y2 = 0.

[0121] In a specific embodiment, A may particularly include at least Y, and B may particularly include at least Al.

[0122] Alternatively or additionally, the luminescent material may include a luminescent material of type A3Si6N 11 :Ce 3+ , where A includes one or more of Y, La, Gd, Tb, and Lu, such as one or more of La and Y in each embodiment.

[0123] In each embodiment, the luminescent material may alternatively or additionally include MS:Eu 2+ and / or M2Si5N8:Eu 2+ and / or MalSiN3:Eu 2+ and / or Ca2AlSi3O2N5:Eu 2+etc., wherein M includes one or more of Ba, Sr and Ca, and in particular, in each embodiment includes at least Sr. Thus, in each embodiment, the luminescence 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 divalent or only divalent and replaces one or more of the indicated divalent cations. Generally speaking, Eu is present in an amount not greater than 10% of the cations; it is present in an amount particularly in the range of about 0.5% to 10%, more particularly, in the range of about 0.5% to 5%, relative to the cation(s) it replaces. The term ":Eu" indicates that a portion of the metal ion is replaced by Eu (in these examples, by Eu). 2+ For example, assuming that the Eu content in CaAlSiN3:Eu is 2%, the correct chemical formula may be (Ca 0.98 Eu 0.02 )AlSiN3. Divalent europium will generally replace divalent cations, such as the above divalent alkaline earth metal cations, in particular, Ca, Sr or Ba. The material (Ba,Sr,Ca)S:Eu can also be indicated as MS:Eu, wherein M is one or more elements selected from the group consisting of barium (Ba), strontium (Sr) and calcium (Ca); in particular, M includes calcium or strontium, or calcium and strontium, more in particular, calcium in the compound. Here, Eu is introduced and replaces at least a portion of M (i.e., one or more of Ba, Sr and Ca). Further, the material (Ba,Sr,Ca)2Si5N8:Eu can also be indicated as M2Si5N8:Eu, wherein M is one or more elements selected from the group consisting of barium (Ba), strontium (Sr) and calcium (Ca); in particular, M includes Sr and / or Ba in the compound. In another specific embodiment, M consists of Sr and / or Ba (excluding the presence of Eu), in particular, 50% to 100%, more in particular, 50% to 90% Ba and 50% to 0% (in particular, 50% to 10%) Sr, such as Ba 1.5 Sr 0.5Si5N8:Eu (i.e., 75% Ba; 25% Sr). Here, Eu is introduced and replaces at least a portion of M (i.e., one or more of Ba, Sr and Ca). Similarly, the material (Ba, Sr, Ca)AlSiN3:Eu can also be indicated as MalSiN3:Eu, wherein M is one or more elements selected from the group consisting of barium (Ba), strontium (Sr) and calcium (Ca); in particular, M in the compound includes calcium or strontium, or calcium and strontium, more in particular calcium. Here, Eu is introduced and replaces at least a portion of M (i.e., one or more of Ba, Sr and Ca). As known to those skilled in the art, Eu in the luminescent materials indicated above is substantially in or only in a divalent state.

[0124] In various embodiments, the red light emitting material may include one or more materials selected from the group consisting of (Ba, Sr, Ca) S: Eu, (Ba, Sr, Ca) AlSiN3: Eu, and (Ba, Sr, Ca) 2 Si5N8: Eu. In these compounds, europium (Eu) is substantially divalent or only divalent and replaces one or more of the indicated divalent cations. Typically, Eu is present in an amount not greater than 10% of the cations; its presence is particularly in the range of about 0.5% to 10%, more particularly, in the range of about 0.5% to 5%, relative to the cation(s) it replaces. The term ": Eu" indicates that a portion of the metal ion is replaced by Eu (in these examples, by Eu). 2+ For example, assuming that the Eu content in CaAlSiN3:Eu is 2%, the correct chemical formula may be (Ca 0.98 Eu 0.02 )AlSiN 3. The divalent europium will generally replace a divalent cation, such as the above-mentioned divalent alkaline earth metal cations, in particular, Ca, Sr or Ba.

[0125] The material (Ba, Sr, Ca) S: Eu can also be indicated as 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 in the compound includes calcium or strontium, or calcium and strontium, more particularly calcium. Here, Eu is introduced and replaces at least a portion of M (i.e., one or more of Ba, Sr, and Ca).

[0126] Further, the material (Ba, Sr, Ca) 2 Si 5 N 8 : Eu may also be indicated as M 2 Si 5 N 8 : Eu, wherein M is one or more elements selected from the group consisting of barium (Ba), strontium (Sr) and calcium (Ca); in particular, M includes Sr and / or Ba in the compound. In another specific embodiment, M consists of Sr and / or Ba (excluding the presence of Eu), in particular, 50% to 100%, more particularly, 50% to 90% of Ba and 50% to 0% (in particular, 50% to 10%) of Sr, such as Ba. 1.5 Sr 0.5 Si5N8:Eu (ie, 75% Ba; 25% Sr). Here, Eu is introduced and replaces at least a portion of M (ie, one or more of Ba, Sr, and Ca).

[0127] Similarly, the material (Ba, Sr, Ca) AlSiN3: Eu can also be indicated 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 the compound includes calcium or strontium, or calcium and strontium, more particularly calcium. Here, Eu is introduced and replaces at least a portion of M (i.e., one or more of Ba, Sr, and Ca).

[0128] As known to those skilled in the art, Eu in the above-indicated luminescent materials is predominantly or exclusively in a divalent state.

[0129] The blue light emitting material may include YSO (Y2SiO5:Ce 3+ ) or similar compounds, or BAM (BaMgAl 10 O 17 :Eu 2 + ) or similar compounds.

[0130] (Also) applicable red luminescent materials may include M' doped with tetravalent manganese x M 2-2x AX6, wherein M' comprises an alkaline earth cation, wherein M comprises a cation, and x is in the range of 0 to 1, wherein A comprises a tetravalent cation, and wherein X comprises a monovalent anion, including at least fluorine.

[0131] The term "luminescent material" in this context particularly relates to inorganic phosphors.

[0132] Alternatively or additionally, other luminescent materials may be used, such as quantum dots and / or organic dyes, which may be optionally embedded in a transmissive matrix, such as a polymer (e.g., PMMA or polysiloxane).

[0133] Quantum dots are small crystals of semiconductor material, which typically have a width or diameter of only a few nanometers. When excited by incident light, the quantum dot emits light of a color determined by the size and material of the crystal. Therefore, light of a specific color can be produced by adapting the size of the dots. Most known quantum dots with emission 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 can also be used, such as indium phosphide (InP) and copper indium sulfide (CuInS2) and / or silver indium sulfide (AgInS2). Quantum dots show very narrow emission bands, so they show saturated colors. Furthermore, the emission color can be easily tuned by adapting the size of the quantum dots. Any type of quantum dot known in the art can be used in the present invention. However, for environmental safety and concerns, it may be preferred to use cadmium-free quantum dots, or at least quantum dots with very low cadmium content.

[0134] Instead of or in addition to quantum dots, other quantum confinement structures may also be used. In the context of this application, the term "quantum confinement structure" should be understood as meaning, for example, quantum wells, quantum dots, quantum rods, tripods, tetrapods or nanowires.

[0135] Organic phosphors may also be used. Examples of suitable organic phosphor materials are organic luminescent materials based on perylene derivatives, for example, compounds sold by BASF under the name PHOSPHATE(R). Examples of suitable compounds include, but are not limited to: Red F305, Orange F240, Yellow F083 and F 170.

[0136] Different luminescent materials may have different spectral power distributions of the respective luminescent material light. Alternatively or additionally, such different luminescent materials may in particular have different color points (or dominant wavelengths).

[0137] As indicated above, other luminescent materials may also be possible. Thus, in a specific embodiment, the luminescent material is selected from the group consisting of: a nitride containing divalent europium, an oxynitride containing divalent europium, a silicate containing divalent europium, a garnet containing cerium, and a quantum structure. The quantum structure may, for example, comprise quantum dots or quantum rods (or other quantum-type particles) (see above). The quantum structure may also comprise a quantum well. The quantum structure may also comprise a photonic crystal.

[0138] In various embodiments, the luminescent material may include a first luminescent material configured to generate a first luminescent material light. More particularly, the first luminescent material may be configured to generate a first luminescent material light having a spectral power at one or more wavelengths in the green-yellow wavelength range. Thus, in various embodiments, the device light may include at least blue light, and the luminescent material may be configured to convert the blue device light into a green-yellow luminescent material light, such as yellow luminescent material light. Furthermore, the first luminescent material may be A3B5O 12 :Ce type. In particular, 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. Therefore, in a specific embodiment, the device light includes at least blue light; wherein the luminescent material includes a first luminescent material, the first luminescent material being configured to generate a first luminescent material light having a spectral power at one or more wavelengths in the green-yellow wavelength range; wherein the first luminescent material is A3B5O 12 :Ce, wherein A includes one or more of Y, La, Gd, Tb and Lu, and wherein B includes one or more of Al, Ga, In and Sc.

[0139] Thus, in various embodiments, the first luminescent material may be configured to generate first luminescent material light having a spectral power at one or more wavelengths in the green-yellow wavelength range.

[0140] In other embodiments, the luminescent material may include a second luminescent material. In particular, the second luminescent material may be configured to convert at least a portion of the (blue) device light into a second luminescent material light having a spectral power distribution different from that of the first luminescent material light. More particularly, the second luminescent material light may have a spectral power at one or more wavelengths in the orange-red wavelength range. Therefore, in a specific embodiment, the light generating system includes a second luminescent material, which is configured to convert at least a portion of the device light into a second luminescent material light having a spectral power distribution different from that of the first luminescent material light, wherein the second luminescent material light has a spectral power at one or more wavelengths in the orange-red wavelength range. In particular, in each embodiment, the second luminescent material may (also) be A3B5O 12 :Ce type, wherein A includes one or more of Y, La, Gd, Tb, and Lu, and wherein B includes one or more of Al, Ga, In, and Sc. Therefore, the second luminescent material may include the materials described above. However, the first luminescent material and the second luminescent material may be different. That is, the first luminescent material and the second luminescent material may be selected so that the first luminescent material light and the second luminescent material light may have different spectral power distributions. For example, the first luminescent material light and the second luminescent material light may have different color points.

[0141] In a specific embodiment, the colors or color points of the first type of light and the second type of light may be different when the corresponding color points of the first type of light and the second type of light differ by at least 0.01 for u' and / or at least 0.01 for v' (even more specifically at least 0.02 for u' and / or at least 0.02 for v'). In a still more specific embodiment, the corresponding color points of the first type of light and the second type of light may differ by at least 0.03 for u' and / or at least 0.03 for v'. Here, u' and v' are the color coordinates of the light in the CIE 1976 UCS (Uniform Chromaticity Scale) diagram. The spectral power distributions of different light sources whose centroid wavelengths differ by at least 10 nm, such as at least 20 nm or even at least 30 nm, may be considered to be different spectral power distributions, e.g., different colors. Generally speaking, the difference in centroid wavelength will be no greater than about 400 nm, such as no greater than 350 nm.

[0142] For example, in various embodiments, the light generating system may include a first luminescence conversion arrangement (configured to generate luminescent material light having a wavelength in the green-yellow wavelength range) and a second luminescence conversion arrangement (configured to generate a second luminescent material light having a wavelength in the orange-red wavelength range).

[0143] In other embodiments, the light generating system may include a single luminescence conversion arrangement comprising a first luminescent material and a second luminescent material. In particular, in various embodiments, the luminescence conversion arrangement may include a rotatable device configured to support the luminescent material (e.g., a ring of luminescent material). For example, in various embodiments, the luminescent material may include alternating segments of the first luminescent material and the second luminescent material (including a ring comprising alternating segments of the first luminescent material and the second luminescent material). In other embodiments, the luminescent material may include a first ring of the first luminescent material and a second ring of the second luminescent material, the first ring of the first luminescent material being concentric with the second ring of the second luminescent material. In still other embodiments, the luminescent material may include a mixture of the first luminescent material and the second luminescent material.

[0144] Note that the term "second luminescent material" may refer to a single type of luminescent material, but in specific embodiments, may also refer to two or more different types of (second) luminescent materials.

[0145] Thus, in various embodiments, the luminescence conversion arrangement can include two luminescent materials. Furthermore, the luminescence conversion arrangement can include two or more luminescent materials. In particular, the two or more luminescent materials can be selected from the group consisting of a yellow luminescent material, a red luminescent material, and a green luminescent material. More particularly, in various embodiments, the two or more luminescent materials can be supported by, for example, a phosphor wheel. In such embodiments, the two or more luminescent materials can be in thermal contact with the phosphor wheel.

[0146] Similar to how a light generating system may comprise one or more luminescence conversion arrangements, a light generating system may (also) comprise one or more diffuser arrangements.

[0147] In various embodiments, the light generating system may include a first diffuser arrangement and a second diffuser arrangement. The diffuser arrangement has been described in more detail above. Furthermore, the one or more light generating devices may include a first light generating device, a second light generating device, and a third light generating device. In particular, the first light generating device may be configured to generate first device light. More particularly, the first device light may have a wavelength within a blue wavelength range. Further, the second light generating device may be configured to generate second device light. In particular, the second device light may (also) have a wavelength within a blue wavelength range. Still further, the third light generating device may be configured to generate third device light. In particular, the third device light may have a wavelength within a red wavelength range. In various embodiments, the luminescence conversion arrangement may be configured to be in a light-receiving relationship with the first light generating device (and convert at least a portion of the first device light into luminescent material light) and may be configured to provide (yellow-green) luminescent material light. Further, in various embodiments, the first diffuser arrangement may be configured to be in a light-receiving relationship with the second light generating device (and generate at least a portion of the diffused (second) device light). As described above, the luminescent conversion arrangement and the first diffuser arrangement can be configured to generate luminescent material light and diffused (second) device light. Further still, in various embodiments, the second diffuser arrangement can be configured to be in a light receiving relationship with the third light generating device (and to generate at least a portion of the diffused (third) device light). In particular, the second diffuser arrangement can be configured to generate diffused third device light from at least a portion of the third device light received by the second diffuser arrangement. Therefore, in such an embodiment, the light generating system can be configured to generate system light, which, in the operating mode of the light generating system, includes: (i) diffused device light, (ii) luminescent material light, and (iii) diffused third device light. In such an embodiment, the light generating system may also include a control system (as described above) configured to control the first light generating device, the second light generating device, and the third light generating device.Therefore, in a specific embodiment, the light generating system includes a first diffuser arrangement and a second diffuser arrangement, wherein the one or more light generating devices include a first light generating device, a second light generating device and a third light generating device, wherein the first light generating device is configured to generate first device light, wherein the second light generating device is configured to generate second device light, and wherein the third light generating device is configured to generate third device light; wherein the luminescent conversion arrangement is configured to be in a light receiving relationship with the first light generating device and is configured to provide luminescent material light; wherein the first diffuser arrangement is configured to be in a light receiving relationship with the second light generating device; wherein the second diffuser arrangement is configured to be in a light receiving relationship with the third light generating device; wherein the second diffuser arrangement is configured to: generate diffused third device light from at least a portion of the third device light received by the second diffuser arrangement; wherein the light generating system is configured to generate system light, which, in an operating mode of the light generating system, includes (i) diffused (second) device light, (ii) luminescent material light and (iii) diffused (third) device light.

[0148] Thus, in various embodiments, the first diffuser arrangement can be configured to generate blue diffused (first) device light. Further, in such embodiments, the second diffuser arrangement can be configured to generate red diffused (third) device light. Thus, the light generating system can generate white system light that includes (i) blue diffused (first) device light, (ii) green-yellow luminescent material light, and (iii) red diffused (third) device light.

[0149] Furthermore, white light can be generated using only a diffuser arrangement (i.e., without using a luminescence conversion arrangement). For example, in various embodiments, a light generating system can include a first diffuser arrangement, a second diffuser arrangement, and a third diffuser arrangement configured in an RGB configuration. Such embodiments can be beneficial because heat generation of the luminescent material and the main body of the phosphor wheel can be omitted.

[0150] Thus, in various embodiments, the alternative light generating system may include a first diffuser arrangement, a second diffuser arrangement, and a third diffuser arrangement as described above. In short, in particular, the alternative light generating system may include a first light generating device configured to provide a first device light having a wavelength in the blue wavelength range to the first diffuser arrangement. In various embodiments, the first diffuser arrangement may convert the blue first device light into blue diffused (first) device light.

[0151] Further, the alternative light generating system may include a second light generating device (or one or more second light generating devices) configured to provide second device light having a wavelength in the red wavelength range to the second diffuser arrangement. In various embodiments, the second diffuser arrangement may convert the red second device light into red diffused second device light.

[0152] Still further, the alternative light generating system may include a third light generating device (or one or more third light generating devices) configured to provide third device light having a wavelength in a green wavelength range to the third diffuser arrangement. In various embodiments, the third diffuser arrangement may convert the green third device light into green diffused third device light.

[0153] Thus, in various embodiments, the alternative light generating system may be configured to generate white system light comprising blue first diffused device light, red second diffused device light, and green third diffused device light in an operating mode of the alternative light generating system.

[0154] However, in the present invention, the system light may include at least the luminescent material light and the diffused device light. In various embodiments, in the operating mode of the light generating system, the system light may specifically include white light. In particular, the system light may include white light having a correlated color temperature in the range of 1800K to 10,000K, such as 7,000K to 10,000K, or 2,000K to 10,000K, and a color rendering index of at least 70, more particularly at least 80. Therefore, in various embodiments, in the operating mode of the light generating system, the system light may include white light having a correlated color temperature in the range of 2,000K to 10,000K and a color rendering index of at least 80. In specific embodiments, the CCT may be selected from the range of 2,000K to 6,500K, such as from the range of 2,700K to 6,500K.

[0155] The term "white light" and similar terms herein are known to those skilled in the art. They may particularly relate to light having a correlated color temperature (CCT) between approximately 1800K and 20,000K, such as between 2000K and 20,000K, particularly between 2700K and 20,000K, for general lighting, particularly in the range of approximately 2000K to 7000K, such as between 2700K and 6500K. In various embodiments, for example, for backlighting purposes or other purposes, the correlated color temperature (CCT) may particularly be in the range of approximately 7000K and 20,000K. Still further, in various embodiments, the correlated color temperature (CCT) is particularly within approximately 15 SDCM (standard deviation of color matching) from the BBL (blackbody locus), particularly within approximately 10 SDCM from the BBL, and even more particularly within approximately 5 SDCM from the BBL.

[0156] In a specific embodiment, the correlated color temperature (CCT) can be selected from the range of 6000K to 12000K, such as from the range of 7000K to 12000K, such as at least 8000K. Still further, in various embodiments, the correlated color temperature (CCT) can be selected from the range of 6000K to 12000K, such as from the range of 7000K to 12000K, with a CRI of at least 70. In a specific embodiment, the correlated color temperature (CCT) can be selected from the range of 2000K to 10000K, with a color rendering index (CRI) of at least 70, such as at least 80.

[0157] In another aspect of the invention, the present invention provides a diffuser arrangement (per se), wherein the diffuser arrangement comprises a polarization beam splitter, a quarter wave plate, a polarization maintaining diffuser and a specular reflector, wherein the reflector comprises a metal reflector; and wherein the diffuser arrangement comprises a secondary second optical element, wherein the secondary second optical element is configured between the quarter wave plate and the polarization maintaining diffuser.

[0158] The polarizing beam splitter, quarter wave plate, polarization-maintaining diffuser, and specularly reflective metal mirror have been described in more detail above.

[0159] In a particular embodiment, the reflector comprises a plane reflector, wherein the diffuser arrangement comprises a first optical element, wherein the first optical element is arranged between a polarization-maintaining diffuser and the reflector, wherein the first optical element is configured to collimate at least a portion of the light passing through the diffuser device into a beam perpendicular to the reflector, wherein the first optical element comprises a lens (or even one or more lenses).

[0160] In other specific embodiments, the reflector comprises a curved reflector, wherein at least a portion of the light passing through the diffuser is reflected perpendicularly from the curved reflector. The light generating system can be part of or can be used in, for example, office lighting systems, home application systems, store lighting systems, furniture lighting systems, accent lighting systems, spotlighting systems, theater lighting systems, fiber optic application systems, projection systems, self-illuminating display systems, pixelated display systems, segmented display systems, warning sign systems, medical lighting application systems, indicator sign systems, decorative lighting systems, portable systems, motor vehicle applications, (outdoor) road lighting systems, urban lighting systems, greenhouse lighting systems, horticultural lighting, digital projection, or LCD backlighting. The light generating system (or luminaire) can be part of or can be used in, for example, an optical communication system or a disinfection system.

[0161] 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 nm to 780 nm. In this document, UV may particularly refer to wavelengths selected from the range of 190 nm to 380 nm, such as 200 nm to 380 nm. Unless it is clear from the context that the term "light" refers only to visible light, the terms "light" and "radiation" are used interchangeably herein. Thus, the terms "light" and "radiation" may refer to UV radiation, visible light, and IR radiation. In specific embodiments, particularly for lighting applications, the terms "light" and "radiation" refer to (at least) visible light.

[0162] The terms "violet light" or "violet emission" and similar terms particularly relate to light having a wavelength in the range of approximately 380 nm to 440 nm. In specific embodiments, violet light can have a centroid wavelength in the range of 380 nm to 440 nm. The terms "blue light" or "blue emission" and similar terms particularly relate to light having a wavelength in the range of approximately 440 nm to 490 nm (including some violet and cyan hues). In specific embodiments, blue light can have a centroid wavelength in the range of 440 nm to 490 nm. The terms "green light" or "green emission" and similar terms particularly relate to light having a wavelength in the range of approximately 490 nm to 560 nm. In specific embodiments, green light can have a centroid wavelength in the range of 490 nm to 560 nm. The terms "yellow light" or "yellow emission" and similar terms particularly relate to light having a wavelength in the range of approximately 560 nm to 590 nm. In specific embodiments, yellow light can have a centroid wavelength in the range of 560 nm to 590 nm. The terms "orange light" or "orange emission" and similar terms particularly relate to light having a wavelength in the range of approximately 590 nm to 620 nm. In specific embodiments, the orange light may have a centroid wavelength in the range of 590 nm to 620 nm. The terms "red light" or "red emission" and similar terms particularly relate to light having a wavelength in the range of approximately 620 nm to 750 nm. In specific embodiments, the red light may have a centroid wavelength in the range of 620 nm to 750 nm. The terms "cyan light" or "cyan emission" and similar terms may refer to light having a wavelength in the range of approximately 490 nm to 520 nm. In specific embodiments, the cyan light may have a centroid wavelength in the range of 490 nm to 520 nm. The terms "amber light" or "amber emission" and similar terms may particularly relate to light having a wavelength in the range of approximately 585 nm to 605 nm, such as approximately 590 nm to 600 nm. In specific embodiments, the amber light may have a centroid wavelength in the range of 585 nm to 605 nm. The phrase "light of one or more wavelengths within a wavelength range" and similar phrases may specifically indicate that the indicated light (or radiation) has a spectral power distribution with at least one or more intensities at these one or more wavelengths within the indicated wavelength range. For example, a blue-light 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 nm to 495 nm.

[0163] The term "centroid wavelength" (also indicated as λ C ) is known in the art and refers to the wavelength value (of a band in the wavelength spectrum) at which half of the light energy is at the shorter wavelength and half of the energy is at the longer wavelength; the value is expressed in nanometers (nm). It is the wavelength that divides the integral of the spectral power distribution into two equal parts, as shown in the formula λ C=Σλ*I(λ) / (ΣI(λ)), where the summation is performed over the wavelength range of interest and I(λ) is the spectral energy density (i.e., the integral of the product of wavelength and intensity normalized to the integrated intensity over the emission band). The centroid wavelength can be determined, for example, under operating conditions.

[0164] In yet another aspect, the present invention further provides a lamp or lamp fixture comprising a light generating system as defined herein. The lamp fixture may further comprise a housing, optical elements, shutters, etc. The lamp or lamp fixture may further comprise a housing surrounding the light generating system. The lamp or lamp fixture may comprise a light window or housing opening in the housing through which the system light may escape from the housing. In yet another aspect, the present invention further provides a projection device comprising a light generating system as defined herein. In particular, a projection device or "projector" or "image projector" may be an optical device that projects an image (or moving image) onto a surface (such as, for example, a projection screen). The projection device may comprise one or more light generating systems, such as the light generating systems described herein. Therefore, in one aspect, the present invention further provides a lighting device selected from the group of lamps, lamp fixtures, projector devices, disinfection equipment, photochemical reactors, and optical wireless communication devices, comprising a light generating system as defined herein. The lighting device may comprise a housing or carrier configured to accommodate or support one or more elements of the light generating system. For example, in various embodiments, the lighting device may include a housing or carrier configured to house or support one or more of the one or more light generating devices, the luminescence conversion arrangement and the diffuser arrangement.

[0165] The term "light generating device" or "light generating system" (and similar terms) may also be used instead of the term "illumination device" or "illumination system" and similar terms. A lighting device or lighting system may be configured to generate device light (or "illumination device light") or system light (or "illumination system light"). As indicated above, the terms light and radiation may be used interchangeably.

[0166] The lighting apparatus may include a light source. In various embodiments, the device light may include one or more of light source light and converted light source light (such as luminescent material light).

[0167] The lighting system may include a light source. In various embodiments, the system light may include one or more of light source light and converted light source light (such as luminescent material light).

[0168] The term UV radiation may refer to near-UV radiation (NUV) in specific embodiments. Therefore, the term "(N)UV" is also used herein to refer to UV in general and NUV in specific embodiments. The term IR radiation may refer to near-IR radiation (NIR) in specific embodiments. Therefore, the term "(N)IR" is also used herein to refer to IR in general and NIR in specific embodiments.

[0169] Herein, UV (ultraviolet) may particularly refer to wavelengths selected from the range of 190 nm to 380 nm, but in specific embodiments, other wavelengths are also possible.

[0170] In this context, IR (infrared) may particularly refer to radiation having a wavelength selected from the range of 780 nm to 3000 nm, such as 780 nm to 2000 nm (e.g., a wavelength up to about 1500 nm, such as a wavelength of at least 900 nm), but in specific embodiments, other wavelengths are also possible. BRIEF DESCRIPTION OF THE DRAWINGS

[0171] Embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings, in which corresponding reference numerals indicate corresponding parts, and in which:

[0172] Figure 1a to Figure 3 An embodiment and some general aspects of a light generating system 1000 are schematically depicted.

[0173] 4a-4b schematically depict some additional embodiments applying (only) parts of a light generating system as described herein.

[0174] Figure 5 An embodiment of an application is schematically depicted.

[0175] The schematic diagrams are not necessarily drawn to scale. DETAILED DESCRIPTION

[0176] Figures 1a-ab schematically depict some embodiments of the present invention. In various embodiments, the present invention provides a light generating system ("system") 1000, which includes one or more light generating devices 100, a luminescence conversion arrangement 2000, and a diffuser arrangement 4000. The one or more light generating devices 100 can be specifically configured to generate device light 101. In particular, the one or more light generating devices 100 can include a solid-state light source 10. More particularly, the solid-state light source 10 can include one or more of a laser diode and a superluminescent diode.

[0177] Furthermore, in various embodiments, the light generating system 1000 can be configured such that: in an operating mode of the light generating system 1000, (a) at least a portion of the device light 101 propagates to the luminescence conversion arrangement 2000, and (b) at least a portion of the device light 101 propagates to the diffuser arrangement 4000. In particular, the at least a portion of the device light 101 that propagates to the diffuser arrangement 4000 is polarized light having one of a first polarization and a second polarization. Further, in various embodiments, the luminescence conversion arrangement 2000 can include a luminescent material 200 configured to convert at least a portion of the device light 101 received by the luminescent material 200 into luminescent material light 201. In particular, the luminescent material 200 can be configured in a reflective mode with respect to the device light 101 illuminating the luminescent material 200.

[0178] Still further, the diffuser arrangement 4000 can be configured to generate diffused device light 401 from at least a portion of the device light 101 received by the diffuser arrangement 4000. Thus, the diffuser arrangement 4000 can include a polarization beam splitter 410, a quarter-wave plate 420, a polarization-maintaining diffuser 430, and a reflector 440. Herein, the reflector 440 can particularly be a specularly reflective (metal) mirror 440. Furthermore, the polarization beam splitter 410 can be (i) transmissive to one of light having a first linear polarization and light having a second linear polarization, and (ii) reflective to the other of the light having the first linear polarization and light having the second linear polarization. In various embodiments, the quarter-wave plate 420 can be disposed between the polarization beam splitter 410 and the polarization-maintaining diffuser 430. Furthermore, in various embodiments, the polarization-maintaining diffuser 430 can be disposed between the quarter-wave plate 420 and the specularly reflective metal mirror 440. In particular, polarization-maintaining diffuser 430 may be configured as a diffuser for device light 101 having the polarization applied to device light 101 by quarter-wave plate 420 .

[0179] The light generating system 1000 may in particular be configured to generate system light 1001 comprising the diffused device light 401 and the luminescent material light 201 in an operating mode of the light generating system.

[0180] like Figure 1AAs depicted, in some embodiments, the reflector 440 may include a plane mirror 440. In particular, in such embodiments, the diffuser arrangement 4000 may include a first optical element 450, which is disposed between the polarization-maintaining diffuser 430 and the plane mirror 440. More particularly, the first optical element 450 may be configured to collimate at least a portion of the diffuser light 401 into a beam perpendicular to the plane mirror 440. In various embodiments, the first optical element 450 may particularly include a lens.

[0181] like Figure 1B In some other embodiments, the reflector 440 may include a curved reflector 440. In particular, in various embodiments, the reflector 440 may include a concave reflector 440. In such embodiments, at least a portion of the diffuser light 401 may be reflected vertically from the curved reflector 440.

[0182] Furthermore, the reflector 440 may include a metal reflector 440. In particular, in various embodiments, the reflector 440 may include a material selected from the group consisting of aluminum, gold, copper, and silver.

[0183] The light generating system 1000 may further include one or more second optical elements 460, see Figure 1A 、 Figure 1B 、 Figure 3 4 . In particular, one or more secondary optical elements 460 can be configured to collimate the device light 101. More particularly, one or more of the following can be applied: (i) a primary second optical element 460, 460' can be arranged between at least one of the one or more light generating devices 100 and the luminescent material 200, and (ii) a secondary second optical element 460, 460" can be arranged between the wave plate 420 and the diffuser 430.

[0184] The specular reflector 440 can reverse the polarization of the diffuser light 401. Thus, the diffuser light 101, 401 can include different polarizations while propagating through the system 1000. Because the polarization beam splitter 410 can be configured to be transmissive to one of light having a first polarization and light having a second polarization, and reflective to the other of the first polarization and light having the second polarization, this difference can be particularly exploited. In various embodiments, the first polarization and the second polarization can particularly be linear polarizations. In particular, in various embodiments, the polarized light including the first polarization can particularly include one of p-polarization and s-polarization. Furthermore, the polarized light including the second polarization can particularly include the other of p-polarization and s-polarization. Thus, in such embodiments, the first polarization and the second polarization can be diametrically opposed.

[0185] Furthermore, the polarization-maintaining diffuser 430 may include an optically isotropic material. In particular, the polarization-maintaining diffuser 430 may include a material selected from the group consisting of cubic crystals, stress-free glass, and isotropic transparent polymers (such as silicone rubber, PMMA, etc.). The polarization-maintaining diffuser 430 may also include a surface relief, that is, the surface of the polarization-maintaining diffuser 430 may include a (pseudo-random) microstructure of depressions and protrusions, which is not shown here.

[0186] In various embodiments, the quarter wave plate 420 may be configured to convert device light 101 having a first polarization into device light 101 having a first circular polarization. Further, the wave plate 420 may be configured to convert diffused device light 401 having a (second) circular polarization into diffused device light 401 having a second polarization.

[0187] In other embodiments, the luminescence conversion arrangement 2000 may include a dichroic reflector (or "dichroic component") 240 that is arranged downstream of one or more of the one or more light generating devices 100. In particular, the dichroic reflector 240 may be configured to transmit (or reflect) the device light 101 and reflect (or transmit) the luminescent material light 201. More particularly, in embodiments as depicted herein, the primary second optical element 460, 460' may be arranged between the dichroic reflector 240 and the luminescent material 200.

[0188] In various embodiments, the one or more light generating devices 100 may include a first light generating device 110 and a second light generating device 120. In particular, in various embodiments, the first light generating device 110 may be configured to generate a first device light 111, and the second light generating device 120 may be configured to generate a second device light 121. Furthermore, in various embodiments, the luminescence conversion arrangement 2000 may be configured in a light receiving arrangement having the first light generating device 110. Still further, in various embodiments, the diffuser arrangement 4000 may be configured in a light receiving arrangement having the second light generating device 120.

[0189] In various embodiments, the light generating system 1000 may also include only one (type of) light generating device 100, such as Figure 4B In such an embodiment, the light generating system 1000 may further include a beam splitter 500, which is arranged downstream of the light generating device 100, in particular, upstream of both the luminescence conversion arrangement 2000 and the diffuser arrangement 4000. In a specific embodiment, the beam splitter 500 may be the polarization beam splitter 410 included in the diffuser arrangement 4000.

[0190] In other embodiments not depicted here, the beam splitter 500 can be a half-silvered mirror. The half-silvered mirror can be configured to: (i) transmit at least a portion of the device light 101 to the diffuser arrangement 4000, and (ii) reflect at least another portion of the device light 101 to a third optical element. In particular, the third optical element can be configured to reflect the device light 101 so that the device light 101 propagates to the luminescent material 200 included in the luminescence conversion arrangement 2000. More particularly, the third optical element can be a reflector, such as a mirror or a dichroic reflector.

[0191] Thus, the beam splitter 500 may be configured to direct at least a portion of the device light 101 to the luminescence conversion arrangement 2000 and to direct at least another portion of the device light 101 to the diffuser arrangement 4000 .

[0192] Because the light generating system 1000 includes a luminescence conversion arrangement 2000 that includes luminescent material 200, the light generating system 1000 may generate heat. This heat may negatively impact, for example, the performance of the luminescent material 200. Therefore, in various embodiments, the light generating system 1000 may further include a rotatable device 250. In particular, the rotatable device 250 may include one of the group consisting of: a phosphor wheel and a phosphor rod. In particular, the rotatable device 250 may be configured to support the luminescent material 200. More particularly, the rotatable device 250 may be configured to support a ring of luminescent material 200.

[0193] Furthermore, in various embodiments, the rotatable device 250 may include a thermally conductive material, i.e., may include a heat sink or may conduct heat to a heat sink. Thus, for example, the luminescent material 200 disposed on a phosphor wheel may be configured to be in thermal contact with the thermally conductive material. However, in embodiments without a phosphor wheel, the thermally conductive material may also be configured to be in thermal contact with the luminescent material 2200. For example, in various embodiments, the luminescent material 200 may be configured to be in physical contact with the thermally conductive material.

[0194] In various embodiments, the luminescent material 200 may include a first luminescent material 210 configured to generate a first luminescent material light 201. More particularly, the first luminescent material may be configured to generate the first luminescent material light 201 having a spectral power at one or more wavelengths in the green-yellow wavelength range. Thus, in various embodiments, the device light 101 may include at least blue light, and the luminescent material 200 may be configured to convert the blue device light 101 into a green-yellow luminescent material light 201, such as yellow luminescent material light 201. Furthermore, the first luminescent material 210 may be A3B5O 12In particular, 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.

[0195] In other embodiments, the luminescent material 200 may include a second luminescent material 220. In particular, the second luminescent material 220 may be configured to convert at least a portion of the (blue) device light 101 into a second luminescent material light 201 having a different spectral power distribution than the first luminescent material light 201. More particularly, the second luminescent material light 201 may have a spectral power at one or more wavelengths in the orange-red wavelength range.

[0196] For example, Figure 2 As depicted, the luminescent material 200 may include alternating segments of a first luminescent material 210 and a second luminescent material 220 (including a ring including alternating segments of the first luminescent material 210 and the second luminescent material 220) (ie, Figure 2 In other embodiments, the luminescent material 200 may include a first ring of a first luminescent material 210 and a second ring of a second luminescent material 220 (ie, Figure 2 In the left embodiment in FIG, the first ring of the first luminescent material 210 is concentric with the second ring of the second luminescent material 220. In still other embodiments, the luminescent material 200 may include a mixture of the first luminescent material 210 and the second luminescent material 220 (i.e., Figure 2 (the right side embodiment in FIG. 1 ).

[0197] Therefore, in various embodiments, the luminescence conversion arrangement 2000 may include two (or more) luminescent materials 200. In particular, the two (or more) luminescent materials 200 may be selected from the group consisting of a yellow luminescent material 200, a red luminescent material 200 and a green luminescent material 200.

[0198] Figure 3An embodiment of a light generating system 1000 including a first diffuser arrangement 4100 and a second diffuser arrangement 4200 is schematically depicted. Furthermore, the light generating system 1000 includes a first light generating device 110, a second light generating device 120, and a third light generating device 130. Specifically, the first light generating device 110 can be configured to generate a first device light 111. Specifically, the second light generating device 120 can be configured to generate a second (blue) device light 121. Specifically, the third light generating device 130 can be configured to generate a third (red) device light 131. In various embodiments, the luminescence conversion arrangement 2000 can be configured in a light-receiving relationship with the first light generating device 110 and configured to provide (yellow-green) luminescent material light 201. Further, in various embodiments, the first diffuser arrangement 4100 can be configured in a light-receiving relationship with the second light generating device 120 and configured to provide diffused (first) device light 401. Still further, in various embodiments, the second diffuser arrangement 4200 can be configured to be in a light-receiving relationship with the third light-generating device 130. In particular, the second diffuser arrangement 4200 can be configured to generate diffused (third) device light 401′ from at least a portion of the second device light 121 received by the second diffuser arrangement 4200. Thus, in such embodiments, the light-generating system 1000 can be configured to generate system light 1001 that, in an operating mode of the light-generating system 1000, includes: (i) diffused device light 401, (ii) luminescent material light 201, and (iii) diffused third device light 401′.

[0199] Therefore, the system light 1001 may include at least the luminescent material light 201 and the diffused device light 401. In various embodiments, the system light 1001 may include, in particular, white light in the operating mode of the light generating system 1000. In particular, the system light 10001 may include white light having a correlated color temperature in the range of 2000K to 10000K and a color rendering index of at least 80.

[0200] 4 schematically depicts an embodiment of an alternative light generating system 1000′ including a first diffuser arrangement 4100, a second diffuser arrangement 4200, and a third diffuser arrangement 4300 as described above. Briefly, and in particular, the alternative light generating system 1000 may include a first light generating device 110 configured to provide a first device light 111 having a wavelength in a blue wavelength range to the first diffuser arrangement 4100. In various embodiments, the first diffuser arrangement 4100 may convert the blue first device light 111 into a blue first diffused device light 401.

[0201] Further, the alternative light generating system 1000 may include a second light generating device 120 configured to provide second device light 121 having a wavelength in a red wavelength range to a second diffuser arrangement 4200. In various embodiments, the second diffuser arrangement 4200 may convert the red second device light 121 into red diffused second device light 401'.

[0202] Still further, the alternative light generating system 1000 may include a third light generating device 130 configured to provide third device light 131 having a wavelength in the green wavelength range to a third diffuser arrangement 4300. In various embodiments, the third diffuser arrangement 4300 may convert the green third device light 131 into green diffused third device light 401″.

[0203] Thus, in various embodiments, the alternative light generating system 1000 may be configured to generate white system light 1001 that includes blue first diffused device light 401 , red second diffused device light 401 ′, and green third diffused device light 401 ″ in an operating mode of the alternative light generating system 1000 .

[0204] Referring to Figures 1a and 1b, Figure 3 4a to 4b, the first diffuser arrangement may include a polarization-maintaining diffuser that is transmissive to the device light directed thereto. Thus, the device light received by the polarization-maintaining diffuser may be transmitted and diffused (particularly, while substantially maintaining polarization). Similarly, the second diffuser arrangement may include a polarization-maintaining diffuser that is transmissive to the device light directed thereto. Thus, the device light received by the polarization-maintaining diffuser may be transmitted and diffused (particularly, while substantially maintaining polarization). Similarly, the third diffuser arrangement may include a polarization-maintaining diffuser that is transmissive to the device light directed thereto. Thus, the device light received by the polarization-maintaining diffuser may be transmitted and diffused (particularly, while substantially maintaining polarization). Further, with reference to these figures, for example, two alternative embodiments may apply:

[0205] (i) The polarization beam splitter (410) is configured to transmit device light having a first linear polarization. Subsequently, the wave plate is configured to convert the transmitted device light having the first linear polarization (e.g., p-polarized light) into a first circularly polarized light having a first chirality (e.g., left-handedness). Subsequently, the metal reflector is configured to reflect the first circularly polarized light having the first chirality into a second circularly polarized light having a second chirality (e.g., right-handedness). Subsequently, the wave plate is configured to convert the second circularly polarized light having the second chirality into a device light having a second linear polarization (e.g., s-polarized light). The device light having the second linear polarization is rotated 90 degrees relative to the device light having the first linear polarization. Subsequently, the polarization beam splitter (410) reflects the device light having the second linear polarization; or

[0206] (ii) The polarization beam splitter (410) is configured to reflect device light having a first linear polarization. Subsequently, the wave plate is configured to convert the reflected device light having the first linear polarization (e.g., p-polarized light) into a first circularly polarized light having a first chirality (e.g., left-handedness). Subsequently, the metal reflector is configured to reflect the first circularly polarized light having the first chirality into a second circularly polarized light having a second chirality (e.g., right-handedness). Subsequently, the wave plate is configured to convert the second circularly polarized light having the second chirality into a device light having a second linear polarization (e.g., s-polarized light). The device light having the second linear polarization is rotated 90 degrees relative to the device light having the first linear polarization. Subsequently, the polarization beam splitter (410) transmits the device light having the second linear polarization.

[0207] Figure 5 An embodiment of a luminaire 2 comprising a light generating system 1000 as described above is schematically depicted. Reference numeral 301 denotes a user interface, which may be functionally coupled to a control system 300 comprised by or functionally coupled to the light generating system 1000. The control system 300 may be configured to control one or more light generating devices 100, in particular, the first light generating device 110 and the second light generating device 120 (and the third light generating device 130). Figure 5 Also schematically depicted is an embodiment of a lamp 1 comprising a light generating system 1000. Reference numeral 3 indicates a projector device or projector system, which can be used to project an image, such as on a wall, and which can also comprise the light generating system 1000. Thus, Figure 5An embodiment of a lighting device 1200 is schematically depicted. The lighting device 1200 is selected from the group consisting of a lamp 1, a luminaire 2, a projector device 3, a disinfection device, a photochemical reactor, and an optical wireless communication device, and includes a light generating system 1000 as described herein. In various embodiments, such a lighting device can be a lamp 1, a luminaire 2, a projector device 3, a disinfection device, or an optical wireless communication device. Lighting device light escaping from the lighting device 1200 is indicated using reference numeral 1201. Lighting device light 1201 can essentially consist of system light 1001 and, therefore, in specific embodiments, can be 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 a wall.

[0208] The term "plurality" means two or more.

[0209] The terms "substantially" or "essentially" and similar terms herein will be understood by those skilled in the art. The terms "substantially" or "essentially" may also include embodiments with "entirely," "completely," "entirely," etc. Therefore, in various embodiments, the adjectives "substantially" or "essentially" may also be removed. Where applicable, the terms "substantially" or "essentially" may also relate to 90% or higher, such as 95% or higher, in particular 99% or higher, even more particularly 99.5% or higher, including 100%.

[0210] The term "comprise" also includes embodiments wherein the term "comprises" means "consisting of.

[0211] The term "and / or" specifically refers 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 can refer to one or more of item 1 and item 2. The term "comprising" can mean "consisting of" in various embodiments, but can also mean "comprising at least the defined species and optionally one or more other species" in another embodiment.

[0212] Furthermore, the terms first, second, third, etc. in the description and claims are used to distinguish between similar elements and not necessarily to describe a sequential or chronological order. It will be understood that the terms so used are interchangeable under appropriate circumstances, and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein.

[0213] An apparatus, device or system may be described herein as being in operation. As will be apparent to one skilled in the art, the present invention is not limited to methods of operation or apparatus, devices or systems in operation.

[0214] It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims.

[0215] In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

[0216] The use of the verb "comprise" and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. Unless the context clearly requires otherwise, throughout the description and claims, the words "comprise," "comprising," etc. should be interpreted in an inclusive sense rather than an exclusive or exhaustive sense; that is, in the sense of "including but not limited to."

[0217] The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

[0218] The invention can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In a device claim or an apparatus claim or a system claim enumerating several components, several of these components may be implemented by one and the same item of hardware. The fact that certain measures are listed in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. In a further aspect, the invention (therefore) provides a software product which, when run on a computer, is capable of implementing (one or more embodiments of) the mode of operation as described herein.

[0219] The present invention also provides a control system that can control a device, apparatus, or system, or can perform the methods or processes described herein. Furthermore, the present invention also provides a computer program product that, when functionally coupled to or on a computer included in a device, apparatus, or system, controls one or more controllable elements of such a device, apparatus, or system.

[0220] The present invention also applies to an apparatus, device 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 also 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.

[0221] The various aspects discussed in this patent may be combined to provide additional advantages. Further, those skilled in the art will appreciate that embodiments may be combined, and more than two embodiments may be combined. Still further, some of the features may form the basis for one or more divisional applications.

Claims

1. A light generating system (1000) comprising (i) one or more light generating devices (100), (ii) a luminescence conversion arrangement (2000), and (iii) a diffuser arrangement (4000), wherein: - the one or more light generating devices (100) are configured to generate device light (101); wherein the one or more light generating devices (100) include a solid-state light source (10), wherein the solid-state light source (10) includes one or more of a laser diode and a superluminescent diode; wherein the light generating system (1000) is configured such that: in an operating mode of the light generating system (1000), (a) at least a portion of the device light (101) propagates to the luminescence conversion arrangement (2000), and (b) at least a portion of the device light (101) propagates to the diffuser arrangement (4000); wherein the at least a portion of the device light (101) that propagates to the diffuser arrangement (4000) is polarized light including one of a first linear polarization and a second linear polarization; - the luminescence conversion arrangement (2000) comprises a luminescent material (200), the luminescent material (200) being configured to convert at least a portion of the device light (101) received by the luminescent material (200) into luminescent material light (201); wherein the luminescent material (200) is configured in a reflective mode with respect to the device light (101) illuminating the luminescent material (200); - the diffuser arrangement (4000) is configured to generate diffused device light (401) from at least a portion of the device light (101) received by the diffuser arrangement (4000); wherein the diffuser arrangement (4000) comprises a polarization beam splitter (410), a quarter wave plate (420), a polarization maintaining diffuser (430) and a specular reflector (440), the reflector (440) comprising a metal reflector (440); The polarization beam splitter (410) is (i) transmissive to one of the light having the first linear polarization and the light having the second linear polarization, and (ii) reflective to the other of the light having the first polarization and the light having the second linear polarization; - the quarter-wave plate (420) is arranged between the polarization beam splitter (410) and the polarization-maintaining diffuser (430); the polarization-maintaining diffuser (430) is arranged between the quarter-wave plate (420) and the specularly reflecting metal mirror (440); wherein the polarization-maintaining diffuser (430) is configured as a diffuser for the device light (101) having the polarization applied to the device light (101) by the quarter-wave plate (420); - one or more secondary optical elements (460) configured to collimate the device light (101), wherein one or more of the following applies: (i) a primary second optical element (460) is arranged between the one or more light generating devices (100) and the luminescent material (200), and (ii) a secondary second optical element (460) is arranged between the wave plate (420) and the diffuser (430); as well as - the light generating system (1000) is configured to generate system light (1001), the system light (1001) comprising (i) the diffused device light (401) and (ii) the luminescent material light (201) in the operating mode of the light generating system (1000).

2. The light generating system (1000) of claim 1, wherein the reflector (440) comprises a plane reflector, wherein the diffuser arrangement (4000) comprises a first optical element (450), wherein the first optical element (450) is arranged between the polarization-maintaining diffuser (430) and the reflector (440), wherein the first optical element (450) is configured to collimate at least a portion of the diffused device light (401) into a beam perpendicular to the reflector (440), wherein the first optical element (450) comprises a lens.

3. The light generating system (1000) of claim 1, wherein the reflector (440) comprises a curved reflector (440), wherein at least a portion of the diffuser device light (401) is reflected perpendicularly from the curved reflector (440).

4. A light generating system (1000) according to any one of the preceding claims, wherein the polarized light including the first polarization is linearly polarized light, wherein the polarized light including the first polarization includes one of p-polarization and s-polarization, and wherein the polarized light including the second polarization is linearly polarized light, wherein the polarized light including the second polarization includes the other of p-polarization and s-polarization.

5. The light generating system (1000) of any one of the preceding claims, wherein the polarization-maintaining diffuser (430) comprises an optically isotropic material.

6. The light generating system (1000) according to any of the preceding claims, wherein one of the following applies: (i) the polarization beam splitter (410) is configured to transmit the device light (101) having the first linear polarization; the quarter wave plate (420) is configured to convert the transmitted device light having the first linear polarization into a first circularly polarized light having a first chirality; the specularly reflecting metal mirror (440) is configured to reflect the first circularly polarized light having the first chirality into a second circularly polarized light having a second chirality; the quarter wave plate (420) is configured to convert the second circularly polarized light having the second chirality into a device light having a second linear polarization, wherein the device light having the second linear polarization is rotated 90° relative to the device light having the first linear polarization; the polarization beam splitter (410) is configured to reflect the device light having the second linear polarization; (ii) the polarization beam splitter (410) is configured to reflect the device light having the first linear polarization; the quarter wave plate (420) is configured to convert the reflected device light having the first linear polarization into a first circularly polarized light having a first chirality; the specularly reflecting metal mirror (440) is configured to reflect the first circularly polarized light having the first chirality into a second circularly polarized light having a second chirality; the quarter wave plate (420) is configured to convert the second circularly polarized light having the second chirality into a device light having the second linear polarization, wherein the device light having the second linear polarization is rotated 90° relative to the device light having the first linear polarization; and the polarization beam splitter (410) is configured to transmit the device light having the second linear polarization.

7. A light generating system (1000) according to any of the preceding claims, wherein the luminescent conversion arrangement (2000) further comprises a dichroic reflector (240), the dichroic reflector (240) being arranged downstream of one or more light generating devices in the light generating devices (100), wherein the dichroic reflector (240) is arranged to transmit device light (101) and reflect luminescent material light (201), and wherein the primary second optical element (460) is arranged between the dichroic reflector (240) and the luminescent material (200).

8. A light generating system (1000) according to any one of the preceding claims, wherein the one or more light generating devices (100) include a first light generating device (110) and a second light generating device (120), wherein the first light generating device (110) is configured to generate a first device light (111), wherein the second light generating device (120) is configured to generate a second device light (121), wherein the luminescent conversion arrangement (2000) is configured to be in a light receiving relationship with the first light generating device (110), and wherein the diffuser arrangement (4000) is configured to be in a light receiving relationship with the second light generating device (120).

9. The light generating system (1000) according to any one of the preceding claims, wherein the light generating system (1000) further comprises a rotatable device (250), wherein the rotatable device (250) is configured to support the luminescent material (200); wherein the rotatable device (250) comprises a thermally conductive material.

10. The light generating system (1000) of any preceding claim, wherein the device light (101) comprises at least blue light; wherein the luminescent material (200) comprises a first luminescent material (210) configured to generate a first luminescent material light (211) having a spectral power at one or more wavelengths in a green-yellow wavelength range; wherein the first luminescent material (210) is A3B5O 12 :Ce type, wherein A includes one or more of Y, La, Gd, Tb and Lu, and wherein B includes one or more of Al, Ga, In and Sc.

11. The light generating system (1000) of claim 10, wherein the light generating system (1000) comprises a second luminescent material (220) configured to convert at least a portion of the device light (101) into a second luminescent material (221) having a spectral power distribution different from that of the first luminescent material light (211); wherein the second luminescent material light (221) has a spectral power at one or more wavelengths in the orange-red wavelength range.

12. A light generating system (1000) according to any of the preceding claims, wherein the luminescence conversion arrangement (2000) comprises two or more luminescent materials (210, 220, ...), wherein the two or more luminescent materials (210, 220, ...) are selected from the group comprising a yellow luminescent material, a red luminescent material and a green luminescent material.

13. The light generating system (1000) according to any one of the preceding claims, wherein the light generating system (1000) comprises a first diffuser arrangement (4100) and a second diffuser arrangement (4200), wherein: - the one or more light generating devices (100) include a first light generating device (110), a second light generating device (120), and a third light generating device (130), wherein the first light generating device (110) is configured to generate a first device light (111), wherein the second light generating device (120) is configured to generate a second device light (121), and wherein the third light generating device is configured to generate a third device light (131); - the luminescence conversion arrangement (2000) is arranged in a light receiving relationship with the first light generating device (110) and is arranged to provide the luminescent material light (201); - said first diffuser arrangement (4100) being arranged in a light receiving relationship with said second light generating device (120) and being arranged to provide said diffused device light (401); - the second diffuser arrangement (4200) is configured in a light receiving relationship with the third light generating device (130); wherein the second diffuser arrangement (4200) is configured to generate diffused third device light (401') from at least a portion of the second device light (121) received by the second diffuser arrangement (4200); - the light generating system (1000) is configured to generate system light (1001), the system light (1001) comprising, in the operating mode of the light generating system (1000), (i) the diffused device light (401), (ii) the luminescent material light (201) and (iii) the diffused third device light (401').

14. The light generating system (1000) of any preceding claim, wherein the system light (1001) comprises white light having a correlated color temperature in the range of 2000 K to 10000 K and a color rendering index of at least 80 in the operating mode of the light generating system (1000); and wherein the solid-state light source (10) comprises a laser diode.

15. A lighting device (1200) selected from the group of a lamp (1), a luminaire (2), a projector device (3) and a stage lighting device, comprising a light generating system (1000) according to any one of the preceding claims.

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