Laser illumination system with optical fiber

Abstract

The present invention provides a light-generating system comprising a light-generating device, an optical fiber, and a light-generating unit. In particular, the light-generating device may be configured to generate a device light having a first wavelength, and the light-generating device includes a solid-state light source. In particular, the optical fiber may include an elongated body of a light-transmitting material that is transparent to the device light having the first wavelength. Furthermore, the optical fiber may include a light entrance portion. In particular, the optical fiber may have a length L1 and an elongated outer surface over at least a portion of the length L1. In particular, the optical fiber may be configured such that when the device light having the first wavelength is irradiated to the light entrance portion, a second light exits the optical fiber through the elongated outer surface over at least a portion of the length L1. Furthermore, the light-generating unit may include a light chamber. In particular, the light chamber may have a reflective inner surface that is reflective to the second light, and a chamber exit window that is transparent to the second light. Moreover, at least a portion of the optical fiber having the chamber fiber length L2 may be configured to have n1 bends in a plane parallel to the length axis A of the optical fiber 500 within the light chamber, where n1≧1. In particular, the light generation system may be configured to generate a system light that includes at least a portion of the second light that exits the light chamber through the chamber exit window.

Description

[Technical field]

[0001] The present invention relates to a light-producing system comprising an optical fiber.The present invention further relates to a lighting device comprising a light-producing system. [Background technology]

[0002] Optical fiber-based illumination systems are known in the art. For example, WO2021040623(A1) describes an optical fiber including a core region having a scattering structure defined therein, the scattering structure being twisted about a longitudinal axis of the core region, the scattering structure being configured to scatter light propagating in the optical fiber out of the optical fiber. An illumination device having an optical fiber and a method for forming an optical fiber are also described in WO2021040623(A1).

[0003] US Patent Application Publication No. 2010 / 238374(A) discloses a backlight having a fiber lamp. The fiber lamp has a side-emitting fiber having a core layer for guiding light and a cladding layer disposed around the core layer. The cladding layer allows light to be extracted from a surface of the cladding layer. A light source is disposed on one or both of a pair of end faces of the side-emitting fiber and emits monochromatic light. A phosphor layer is disposed on the surface of the cladding layer.

[0004] DE 10 2006 061 164 A1 discloses a light-emitting device comprising a radiation source for emitting radiation of at least a first wavelength and an elongated curved light guide into which the radiation emitted by the radiation source is coupled and which separates light at an angle to its longitudinal axis due to the coupled-in radiation of the first wavelength. Summary of the Invention [Problem to be solved by the invention]

[0005] The use of optical fibers to transmit light is known in the art. However, light generating systems that utilize the transmission of light from the surface of an optical fiber are still being actively developed. Light generating systems known in the art may require additional light sources to be configured within the system. This may be disadvantageous since the light source may have to be housed within such a light generating system. This may result in (i) undesirable heating of the system, (ii) a requirement to route power to the system, and (iii) cumbersome maintenance in case of malfunction.

[0006] The use of laser light sources is known in the art, however, providing distributed lighting over a spatial area (e.g., in an office, a room, a car) using a single laser light source remains a challenge. Providing lighting systems in building materials such as concrete walls or between glass panels is difficult, especially if light sources and power supply units must (also) be constructed in these locations.

[0007] Mixing light from different sources to provide multiple lights of different colors, wavelengths, and spectral power distributions may require the use of multiple light sources, which may increase the complexity of the system (due to the large number of elements that must be configured in the system). The use of multiple light sources may make the light-generating system bulky and difficult to maintain. This may be disadvantageous, especially when the light-generating system is configured in less than ideal locations, such as, for example, in building materials, in the interior lining of a car, etc. [Means for solving the problem]

[0008] It is therefore an aspect of the present invention to provide an alternative light generating system, which preferably also at least partially obviates one or more of the above-mentioned disadvantages. The present invention may have as an object to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative.

[0009] According to a first aspect, the present invention provides a light-generating system ("system"). In an embodiment, the light-generating system may comprise a light-generating device ("device"). In particular, the light-generating system may comprise an optical fiber. The light-generating system may comprise, in an embodiment, a light-generating unit. Hence, in an embodiment, the light-generating system may comprise a light-generating device, an optical fiber, and a light-generating unit. Furthermore, in an embodiment, the light-generating device may be configured to generate device light. In particular, in an embodiment, the device light may have a first wavelength. In an embodiment, the light-generating device may comprise a solid-state light source. In an embodiment, the optical fiber may comprise an elongated body of optically transparent material. Furthermore, the elongated body of optically transparent material may be transparent to the device light having the first wavelength. Furthermore, the optical fiber may comprise a light input portion. In an embodiment, the optical fiber may have a length L1 (or a total fiber length). Furthermore, in an embodiment, the optical fiber may have an elongated outer surface over at least a portion of its length L1. The light input portion of the optical fiber may be illuminated with the device light. In particular, the optical fiber may be configured such that, upon irradiation of the light input with device light (having a first wavelength), the second light exits the optical fiber through the elongated outer surface over at least a portion of its length L1. In an embodiment, the light generating unit may include a light chamber ("chamber"). Furthermore, the light chamber may have a reflective inner surface. Furthermore, the light chamber may be reflective to the second light. In an embodiment, the light chamber may have a chamber exit window. The chamber exit window may be transparent to the second light. Thus, the light chamber may have a reflective inner surface (reflective to the second light) and a chamber exit window (transmissive to the second light). In an embodiment, at least a portion of the optical fiber may have a chamber fiber length L2. In particular, at least a portion of the optical fiber (having the chamber fiber length L2) may be configured in the optical chamber. At least a portion of the optical fiber (having the chamber fiber length L2) may have n1 bends in a plane parallel to the length axis (A) of the optical fiber.Furthermore, in an embodiment, at least a portion of the optical fiber configured in the light chamber may have n1 bends, where n1≧1. In an embodiment, the light-generating system may be configured to generate a system light. In particular, the system light may include at least a portion of the second light. Furthermore, the system light (including at least a portion of the second light) may at least exit the light chamber through a chamber exit window. Therefore, in a particular embodiment, the present invention provides a light-generating system comprising a light-generating device, an optical fiber, and a light-generating unit. In particular, the light-generating device may be configured to generate a device light having a first wavelength, the light-generating device including a solid-state light source. Furthermore, the optical fiber may include an elongated body of an optically transparent material that is transparent to the device light having the first wavelength. Furthermore, the optical fiber may include a light entrance portion. In particular, the optical fiber may have a length L1 and an elongated outer surface over at least a portion of the length L1. The optical fiber may be configured such that, when the device light having the first wavelength is irradiated to the light input, the second light exits the optical fiber through the elongated outer surface over at least a portion of its length L1. Furthermore, the light generating unit may include a light chamber. In particular, the light chamber may have a reflective inner surface that is reflective to the second light and a chamber exit window that is transparent to the second light. Furthermore, at least a portion of the optical fiber having the chamber fiber length L2 may be configured to have n1 bends in a plane parallel to the length axis (A) of the optical fiber in the light chamber, where n1≧1. In particular, the light generating system may be configured to generate a system light including at least a portion of the second light (exiting the light chamber through the chamber exit window).

[0010] In such a system, an optical fiber may be used to transmit light along the optical fiber and (also) to provide light from at least a portion of the surface of the optical fiber. The system may provide the advantage of providing a light-generating unit that utilizes this light (provided by the optical fiber). The system may provide the advantage of controlling the intensity, spectral power distribution, and color of the light outcoupled from the light-generating unit. The system may provide the advantage of controlling the aforementioned parameters through a number of configuration choices, such as (i) the spatial orientation of the optical fiber within the light-generating system, (ii) the number of bends the optical fiber has, (iii) the use of luminescent materials on the surface of the optical fiber, and (iv) the degree of scattering of the light outcoupled from the light-generating system. The system may further provide the advantage of using a single optical fiber to illuminate a space (e.g., a car, or an apartment, or an office) by configuring a number of light-generating units, all of which use a single optical fiber. The system may also be used to provide a high-brightness light source that may be used in applications such as projection, stage lighting, spot lighting, and automotive lighting. The (sole) use of optical fibers to provide illumination is advantageous, especially when the illumination system is installed in building materials such as in concrete or between window panes. Furthermore, the light generating system may use a single diode laser to illuminate a large space by means of optical fibers. For example, a flat lamp may be provided using optical fibers.

[0011] In an embodiment, the light generating system comprises an optical fiber. The optical fiber (or "fiber") may be a flexible transparent fiber made by drawing glass (silica), or plastic, or polymer (e.g., Polymethyl Methacrylate (PMMA)). In an embodiment, the optical fiber may include a core, and further includes a core material, such as glass (silica), an optically transparent polymer, or other optically transparent material.

[0012] Total internal reflection (TIR) ​​in this context is known to those skilled in the art as the reflection of light traveling in the core of an optical fiber when it meets and is reflected by the boundary of the core at a steep angle (greater than a certain critical angle). Moreover, it is clear to those skilled in the art that this critical angle can be determined as the arc sine of the ratio of the refractive index of the core material to the refractive index of the material at the boundary of the optical fiber core. It is (further) known to those skilled in the art that the refractive index of a material is defined as a function of the wavelength of the light. In an embodiment, total internal reflection may be used in optical fibers to confine light within the core of the optical fiber. Since the light must hit the boundary (of the core) at an angle greater than the critical angle, only light entering the optical fiber within a certain range of angles can travel down the fiber without escaping. Therefore, optical fibers may have light guiding properties.

[0013] In an embodiment, the optical fiber may also be configured to allow light to escape (or leak) from the outer surface of the optical fiber. The choice of core material may determine the critical angle for total internal reflection. Therefore, in an embodiment, the optical fiber may also be configured to transmit at least a portion of the light traveling in the core to the outside of the optical fiber by hitting a boundary of the optical fiber at an angle smaller than the critical angle. Therefore, light traveling in the optical fiber may be incident on the boundary at an angle smaller than the critical angle, such as when the optical fiber is bent at the point of incidence. This may also result in light outcoupling from the optical fiber. In an embodiment, the optical fiber may be flexible and therefore may be bent or twisted or placed in a myriad of other orientations. Therefore, the optical fiber may also provide illumination. At the bend, light propagating through the optical fiber may escape (see also further below).

[0014] In an embodiment, the optical fiber may be configured to allow light to escape from the optical fiber due to scattering. Scattering structures (for use in (or on) optical fibers) are known in the art, and it will be apparent to one skilled in the art that these structures may be used to configure the optical fiber to outcouple light. In particular, the core of the optical fiber may cause emission through the core boundary or outer surface by scattering elements configured in the core of the optical fiber. Furthermore, the light scattering elements may include linear or thread-like structures along the axis of the optical fiber. Still further, the light scattering elements may include bubbles or particles. Furthermore, in an embodiment, linear light scattering elements may be disposed in the cross section of the optical fiber, which may provide the advantage of improving the degree of directional outcoupling of the device light. Thus, the optical fiber may be configured to propagate at least a portion of the light along the optical fiber and outcouple at least a portion of the light out of the optical fiber. Outcoupling of light from the optical fiber may provide illumination directly or indirectly. Direct illumination may refer herein to illumination from light outcoupled from the optical fiber. Indirect illumination may refer to providing illumination from another system, or unit, or device, or element that comprises an optical fiber, where the term "outcoupling" may refer to photons escaping from a surface, or element, or system, or material, such as an optical fiber.

[0015] In an embodiment, the light-generating system may comprise a light-generating device. In particular, the light-generating device may be a device configured to generate device light, and the device light may have a first wavelength. The term "first wavelength" may also refer to a plurality of different (first) wavelengths. In particular, the device light may be selected from one or more of UV radiation, visible light, or infrared radiation. In particular, the device light may include one or more of violet light, blue light, green light, yellow light, orange light, red light, pink light, cyan light, or amber light. The term "violet light" or "violet emission" particularly relates to light having a wavelength in the range of about 380-440 nm. The term "blue light" or "blue emission" particularly relates to light having a wavelength in the range of about 440-495 nm (including some violet and cyan hues). The term "green light" or "green emission" particularly relates to light having a wavelength in the range of about 495-570 nm. The term "yellow light" or "yellow emission" particularly relates to light having a wavelength in the range of about 570-590 nm. The term "orange light" or "orange emission" particularly relates to light having a wavelength in the range of about 590-620 nm. The term "red light" or "red emission" particularly relates to light having a wavelength in the range of about 620-780 nm. The term "pink light" or "pink emission" refers to light having a blue component and a red component. The term "cyan" may refer to one or more wavelengths selected from the range of about 490-520 nm. The term "amber" may refer to one or more wavelengths selected from the range of about 585-605 nm, for example, about 590-600 nm. Thus, in particular device light and system light include visible light.

[0016] In an embodiment, the optical fiber may comprise an elongated body of optically transparent material. Optically transparent materials are known to those skilled in the art as materials that allow light to be transmitted. The optically transparent material may be transparent to the device light, and in an embodiment, the transmission of the device light through the optically transparent material in a direction perpendicular to its surface may be at least 50%, such as at least about 75%, such as at least 90% in an embodiment, and even more particularly at least about 100%. Furthermore, in an embodiment, the optically transparent material may be a material such as glass or an optically transparent polymer material, such as PMMA. Furthermore, the elongated body of optically transparent material may be transparent to the device light having a first wavelength, i.e. the optically transparent material may be transparent (only) to light having a first wavelength. This may therefore provide the advantage of filtering certain wavelengths, i.e. providing light of a certain color.

[0017] The length of the optical fiber and the type of optically transparent material may be selected such that less than 50% of the device light propagating along the length axis of the optical fiber may be absorbed. In other words, the transmission of the optical fiber over its length may be at least 50%, such as at least 75%, such as at least 90% in embodiments, and even more particularly at least 95%, for device light propagating along the length axis of the optical fiber. For this definition, it is assumed that there is no scattering. Of course, there may be scattering in the optical fiber, which may mean that, for example, less than 95% of the device light is received at the end of the optical fiber.

[0018] In an embodiment, the optical fiber may include a light inlet. The light inlet may essentially be an entry point for the device light. In particular, the light inlet may be configured to receive light from a light-generating device. Furthermore, the light inlet may be directly coupled to the light-generating device, i.e. physically attached to the light source. In a particular embodiment, the device light may be provided to the light inlet via a lens. This may be particularly advantageous in embodiments where the light source does not provide light as a collimated beam. The lens may therefore serve to align the radiation or light of the light source into a collimated beam.

[0019] In particular, the light input may be arranged outside the light chamber. In other embodiments, the light input may be arranged inside the light chamber. The optical fiber may include a light input and a light output (see also below). In particular, at least one of the light input and the light output may be arranged outside the light chamber (see also further below).

[0020] In particular, the optical fiber may have a length (L1). The length (L1) may be defined in embodiments over the entire length of the optical fiber from the light input (where the light source radiation enters the optical fiber) to the light output (i.e. the point along the axis of the optical fiber where the light finally exits the optical fiber). The length L1 may be the length of the optical fiber when the optical fiber is configured in a straight configuration without any bends. It should be noted that the light output does not refer to the boundaries of the optical fiber (where the light may (also) be outcoupled). In particular, the optical fiber may have a length axis (A), which is an imaginary line along the center of the optical fiber and parallel to the boundaries of the optical fiber. Moreover, the length axis may (hence) be straight, or curved, or looped, or may exhibit other configurations. In embodiments, L1 may be at least 2 meters, in particular at least 3 meters, more particularly 4 meters, and most particularly 5 meters. For example, the length L1 may be selected from the range of 2 to 10 m, although other values ​​may also be possible.

[0021] Instead of a light output, in other embodiments there may be an optical fiber end. Device light reaching the optical fiber end may be reflected back towards the light input.

[0022] In embodiments, the optical fiber may have a circular cross-section, a square cross-section, or a regular polygonal cross-section (pentagon, hexagon, etc.).

[0023] Furthermore, the optical fiber may, in embodiments, have an elongated outer surface over at least a portion of its length L1, for example, at least 80%, for example, more particularly at least 90% of its length (L1). In particular, the elongated outer surface may cover at least a portion of the optical fiber such that device light outcoupled from the core of the optical fiber may interact with the elongated outer surface. Furthermore, in embodiments, the elongated outer surface may include an optically transparent material and therefore outcouple device light outcoupled from the core of the optical fiber. In certain embodiments, the optical fiber may have an elongated outer surface over its entire length L1. In some embodiments, the portion of the optical fiber that is not covered by the elongated outer surface may not be optically transparent and therefore may have an opaque layer portion (different from the elongated outer surface) over the portion of the optical fiber that is opaque to the light. This may help to limit undesired leakage or outcoupling of light in these portions. In certain embodiments, the opaque layer portion may be reflective and therefore may reflect scattered light from the light scattering element back into the optical fiber. In particular, the opaque layer portion may include a light blocking coating along a portion of the optical fiber. The light blocking coating may provide the advantage of controlling the second light outcoupled from the optical fiber by selectively allowing light to emanate from only a portion of the optical fiber. In an embodiment, the optical fiber may be illuminated at a light input with device light. In a further embodiment, the optical fiber may be configured such that illumination of the light input with device light (having a first wavelength) causes the second light to exit the optical fiber via the elongated outer surface over at least a portion of its length L1.

[0024] Since the second light may exit the optical fiber via the elongated outer surface, the elongated outer surface may also be referred to as the light emission surface or light exit surface of the optical fiber. In case the optical fiber comprises only a core and not a cladding, the elongated outer surface may be provided by a portion of the outer surface of the core. In case the optical fiber comprises a core and a cladding, the elongated outer surface may be provided by a portion of the outer surface of the cladding. In particular, in an embodiment, the elongated outer surface may therefore be a radially configured surface.

[0025] Furthermore, in an embodiment, the light-generating system may comprise a light-generating unit. In particular, the light-generating system may provide the system light by, among other things, the light-generating unit. Furthermore, the light-generating unit may include a light chamber. In a further embodiment, the light chamber may have a reflective inner surface. In particular, the light chamber may be reflective to the second light. Furthermore, the light chamber may have a chamber exit window. The chamber exit window may be transparent to the second light in an embodiment.

[0026] In particular, in embodiments, the reflective inner surface may be a material such as a polished metal, a mirror including glass (silica), a reflective polymeric material, such as materials such as BaSO4, Al2O3, and MgO. In yet further embodiments, the light chamber may have a reflective inner surface (reflective to the second light) and a chamber exit window (transmissive to the second light). In embodiments, the chamber exit window may include a portion of the light chamber, such as one side of a rectangular (or polyhedral) box that constitutes the light chamber, or one of two sides of a cylinder.

[0027] The chamber exit window may therefore comprise a light-transmitting material such as polyethylene (PE), polyethylene napthalate (PEN), polycarbonate (PC), polyurethane (PU), polymethylacrylate (PMA), polymethylmethacrylate (PMMA) (Plexiglas® or Perspex®), polymethacrylimide (PMI), polymethylmethacrylimide (PMMI), styrene acrylonitrile resin (SAN), cellulose acetate butyrate (CAB), silicone, polyvinylchloride (PVC), and in one embodiment polyethylene terephthalate (PETG), including glycol modified polyethylene terephthalate (PETG). The insulating layer may include one or more materials selected from the group consisting of transparent organic materials, such as selected from the group consisting of poly(ethylene terephthalate; PET), polydimethylsiloxane (PDMS), and cyclo olefin copolymer (COC).In particular, the light-transmitting material may be, for example, polycarbonate (PC), poly(methyl)methacrylate (P(M)MA), polyglycolide or polyglycolic acid (PGA), polylactic acid (PLA), polycaprolactone (PCL), polyethylene adipate (PEA), polyhydroxy alkanoate (PHA), polyhydroxy butyrate (PHB), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polytrimethylene ... The light-transmitting material may comprise an aromatic polyester, or a copolymer thereof, such as one or more of polyethylene terephthalate (PTT), polyethylene naphthalate (PEN). In particular, the light-transmitting material may comprise polyethylene terephthalate (PET). The light-transmitting material is therefore in particular a polymeric light-transmitting material. However, in another embodiment, the light-transmitting material may comprise an inorganic material. In particular, the inorganic light-transmitting material may be selected from the group consisting of glass, (fused) quartz, a transparent ceramic material, and silicone. Also, hybrid materials comprising both inorganic and organic parts may be applied. In particular, the light-transmitting material comprises one or more of PMMA, transparent PC, or glass.

[0028] It should be noted that the optically transparent material of the optical fiber may also be selected from the materials defined above.

[0029] In an embodiment, at least a portion of the optical fiber may be configured within the optical chamber. In a further embodiment, at least a portion of the optical fiber may have a chamber fiber length L2. The length L2 may be the length of the optical fiber configured within the optical chamber. In an embodiment, the length of the fiber within the chamber may be 10% to 95%, particularly 20% to 90%, more particularly 30% to 85%, and most particularly 40% to 80% of the total fiber length (L1). In particular, since at least a portion of the optical fiber may be configured outside the optical chamber (and thus also the light generation unit), L2 is of a length shorter than L1, i.e., L2 < L1. For example, the portion of the optical fiber configured outside the optical chamber may be selected from the range of 10 to 60%, for example 20 to 40%, of the fiber length L1.

[0030] The fiber length and the chamber fiber length may be defined along the elongation axis of the fiber. These lengths may be determined, for example, when the optical fiber is configured in a straight configuration having no curvature at all.

[0031] When the light generation system includes a plurality of optical chambers sharing the same optical fiber, the chamber fiber length may be the cumulative length in each optical chamber.

[0032] In an embodiment, at least a portion of the optical fiber (having a chamber fiber length L2) may have n1 bends in a plane parallel to the length axis (A) of the optical fiber. However, the length axis (A) may be configured in a non-planar configuration in certain embodiments, for example, the optical fiber may be configured in a 3D orientation in the light chamber. Therefore, bends may (also) be configured along the optical fiber in a 3D configuration (in the light chamber). In an embodiment, at least a portion of the optical fiber may have n1 bends, such that n1≧1. By bending the optical fiber, a longer length of the optical fiber may be accommodated in the light generation unit, and more particularly in the light chamber. Here, a bend may refer to any deviation in a linear trajectory along any portion of the optical fiber. Bending the optical fiber may provide the advantage of outcoupling light (device light or second light) at the bend of the optical fiber. This may further provide the advantage of increasing the amount of light (device light or second light) outcoupled from the optical fiber by increasing the number of bends included by the optical fiber. Furthermore, the n1 bends may be distributed within a light chamber (contained by the light-generating unit) such that the bends are distributed according to a particular arrangement (or pattern), which may provide the advantage of controlling the spatial locations within the light-generating unit from which light may be outcoupled.

[0033] In the case where there is more than one light chamber, the number of n1 bends may refer specifically to the bends in one of the light chambers. Thus, the optical fiber may have n1 bends in each light chamber. It should be noted that the number of bends in different light chambers may be the same or different.

[0034] In an embodiment, the plane parallel to the length axis (A) of the optical fiber may in particular be essentially parallel to the chamber exit window of the light chamber and / or essentially parallel to the bottom of the light chamber.

[0035] In particular, the light-generating system may be configured to generate a system light. In an embodiment, the system light may include at least a portion of the second light.

[0036] The light-generating system may in certain embodiments comprise an additional light source arranged in the light-generating unit. In an embodiment, the additional light source may be arranged in the light chamber.

[0037] The additional light sources may provide additional light source light. Furthermore, in embodiments, light outcoupled from the additional light sources may be outcoupled from the light-generating unit via the chamber exit window. These additional light sources may (also) be arranged external to the light-generating unit in certain embodiments. Thus, the system light may include the second light, or the light from the additional light sources, or both.

[0038] In further embodiments, the system light (including at least a portion of the second light) may exit the light chamber at least through a chamber exit window.

[0039] In certain embodiments, the system light may consist essentially of the secondary light.

[0040] In embodiments, the system light exiting the light chamber may include high intensity light. In embodiments, the light generating system may have an output of at least 10,000 lm / mm 2 The high intensity light generating device may be configured to generate device light having an intensity of

[0041] High intensity light, up to approx. 20,000lm / mm 2 The light may be generated by a solid-state light source, such as a static phosphor-converted laser source, capable of providing intensities of

[0042] In an embodiment, the light-generating device may include a solid-state light source. In particular, a light-generating device including a solid-state light source may be configured to provide the device light. The solid-state light source may, in an embodiment, be a blue light source, such as a blue LED, or a green light source, such as a green LED, or a red light source, such as a red LED. Furthermore, the solid-state light source may include a diode laser. In an embodiment, the device light may include a diode laser light. In a further embodiment, the solid-state light source may include a laser (or a "laser light source" or "laser").

[0043] The term "laser light source" refers in particular to a laser. Such a laser may be configured to generate a device light having one or more wavelengths in the UV, visible, or infrared, in particular having a wavelength selected from the spectral wavelength range of 200-2000 nm, for example 300-1500 nm. The term "laser" refers in particular to a device that emits light via a process of light amplification based on stimulated emission of electromagnetic radiation. In particular, in embodiments, the term "laser" may refer to a solid-state laser. A solid-state light source may in embodiments (also) use an organic light-emitting diode (OLED) or a polymer light-emitting diode (PLED) as a source of illumination, rather than an electric filament, a plasma (as used in arc lamps such as fluorescent lamps), or a gas. In embodiments, the term "laser" or "solid-state laser" or "solid-state material laser" refers to any laser including cesium-doped lithium strontium (or calcium) aluminum fluoride (Ce:LiSAF, Ce:LiCAF), chromium-doped chrysoberyl (alexandrite) lasers, chromium ZnSe (Cr:ZnSe) lasers, divalent samarium-doped calcium fluoride (Sm:CaF) lasers, Er:YAG lasers, erbium-doped glass lasers, and erbium-ytterbi lasers. co-doped glass lasers, F-center lasers, Holmium YAG (Ho:YAG) lasers, Nd:YAG lasers, NdCrYAG lasers, neodymium-doped yttrium calcium oxoborate 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 laser, ruby ​​laser (Al2O3:Cr 3+ ), thulium YAG (Tm:YAG) laser, titanium sapphire (Ti:sapphire; Al2O3:Ti 3+) laser, trivalent uranium doped calcium fluoride (U:CaF2) solid-state laser, ytterbium doped glass laser (rod, plate / chip, and fiber), ytterbium YAG (Yb:YAG) laser, Yb2O3 (glass or ceramic) laser, etc. In still further embodiments, the source light may in particular be (collimated) laser source light. In still further embodiments, the light generating device may be one or more of F-center laser, yttrium orthovanadate (Nd:YVO4) laser, promethium-147 doped phosphate glass (147Pm 3+ :glass), and titanium sapphire (Ti:sapphire; Al2O3:Ti 3+) lasers. For example, taking into account second and third harmonic generation, such a light source may be used to generate blue light. The laser may be combined with an upconverter to reach shorter (laser) wavelengths. For example, the upconversion may be obtained by some (trivalent) rare earth ions or may be obtained by nonlinear crystals. Alternatively, the laser may be combined with a downconverter, such as a dye laser, to reach longer (laser) wavelengths. In certain embodiments, the term "laser" or "laser source" or similar terms refer to a diode laser. In embodiments, the term "laser" or "solid-state laser" or "solid-state material laser" may refer to one or more of semiconductor laser diodes, such as GaN, InGaN, AlGaInP, AlGaAs, InGaAsP, lead salt, vertical cavity surface emitting laser (VCSEL), quantum cascade laser, hybrid silicon laser, etc. In further embodiments, the solid-state light source may be a solid-state LED light source (such as an LED or diode laser). In particular, the solid-state light source may be a superluminescent diode. A superluminescent diode (SLED or SLD) is an edge-emitting semiconductor light source based on superluminescence. A superluminescent diode offers the advantage of combining the high power and brightness of a diode laser with the low coherence of a conventional light-emitting diode. A vertical cavity surface-emitting laser, or VCSEL, is known in the art and may be a type of semiconductor laser diode with a vertical laser beam emission from the top surface, in particular as opposed to an edge-emitting semiconductor laser (also called an in-plane laser), which emits from a surface formed by cleaving individual chips from a wafer. A VCSEL may have a tunable emission wavelength, as known in the art.For example, Dupont et al., Applied Physics Letters 98(16):161105 - 161105-3, DOI:10.1063 / 1.3569591, or Wendi Chang et al., Applied Physics Letters 105(7):073303, DOI:10.1063 / 1.4893758, or Thor Ansbaek, IEEE Journal of Selected Topics in Quantum Electronics 19(4):1702306-1702306, DOI:10.1109 / JSTQE.2013.2257164, or CJChang-Hasnain, IEEE Journal of Selected Topics in Quantum Electronics (Volume:6, Issue:6, Nov.-Dec.2000), DOI:10.1109 / 2944.902146, or Kogel et al., IEEE Sensors Journal, December 2007, volume 7, no.11, pages 1483-1489, or Jayaraman, et al., Electron Lett. 2012 Jul 5;48(14):867-869, doi:10.1049 / el.2012.1552, all of which are incorporated herein by reference, describe tunable VCSELs. In particular, varying the voltage can change the spectral power distribution of the VCSEL. The term "VCSEL" may therefore refer in particular to a tunable VCSEL, as known in the art. Such tunable VCSELs may be based on MEMS technology. Such (tunable) VCSELs may also be denoted as "MEMS VCSELs". Thus, in an embodiment, the diode laser may include a vertical cavity surface emitting laser (VCSEL) with single mode emission and long coherence length. Wavelength sweeping may be performed using a micro-electro-mechanical system (MEMS) to vary the length of the laser cavity, resulting in stable and rapid wavelength sweeping.Therefore, a variety of spectral power distributions may be produced using the VCSEL. In particular, the VCSEL may be configured to produce laser light (during operation of the VCSEL).

[0044] As mentioned above, the light input of the optical fiber may be illuminated with the device light. The light input may therefore be arranged in a receiving relationship with the light-generating device, or in other words, the light input may be arranged specifically downstream of the light-generating device. In this way, the device light may be incoupled into the optical fiber.

[0045] Therefore, light exiting the optical fiber through the elongated outer surface may, in embodiments, consist essentially of incoupled device light.

[0046] In an embodiment, the optical fiber may include a luminescent material configured to convert at least a portion of the device light into a converted device light. The solid-state light source may in an embodiment be configured to provide light at a first wavelength, and a portion of the device light having the first wavelength may be converted into the luminescent material light or the converted device light. In particular, the converted device light may be based on conversion by the luminescent material.

[0047] The term "luminescent material" refers in particular to a material capable of converting a first radiation, in particular one or more of UV radiation and blue radiation, into a second radiation. In general, the first radiation and the second radiation have different spectral power distributions. Therefore, instead of the term "luminescent material", the term "luminescence converter" or "converter" may also be applied. In general, the second radiation has a spectral power distribution at a wavelength greater than that of the first radiation, which is the case of so-called down-conversion. However, in certain embodiments, the second radiation has a spectral power distribution with an intensity at a wavelength smaller than that of the first radiation, which is the case of so-called up-conversion.

[0048] In embodiments, "luminescent material" may refer specifically to a material capable of converting radiation, for example, into visible light and / or infrared light. For example, in embodiments, the luminescent material may be capable of converting one or more of UV radiation and blue radiation into visible light. The luminescent material may also convert radiation into infrared radiation (IR) in certain embodiments. Thus, when excited with radiation, the luminescent material emits radiation. Generally, the luminescent material is a down-converter, i.e., radiation of a smaller wavelength is converted into radiation having a larger wavelength (λ ex <λ em ), in certain embodiments, the luminescent material may include an up-converter luminescent material, i.e., radiation of a larger wavelength is converted to radiation having a smaller wavelength (λ ex >λ em ).

[0049] In embodiments, the term "luminescence" may refer to phosphorescence. In embodiments, the term "luminescence" may also refer to fluorescence. Instead of the term "luminescence", the term "emission" may also be used. Thus, the terms "first radiation" and "second radiation" may refer to excitation radiation and luminescence (radiation), respectively. Similarly, the term "luminescent material" may refer to phosphorescence and / or fluorescence in embodiments.

[0050] The term "luminescent material" may also refer to a number of different luminescent materials. Examples of possible luminescent materials are given below. Thus, the term "luminescent material" may also refer to a luminescent material composition in certain embodiments. Instead of the term "luminescent material", the term "phosphor" may also be applied. These terms are known to those skilled in the art. Luminescent materials are known in the art.

[0051] Thus, the system light may include one or more of the device light and the conversion device light. Thus, in an embodiment, the second light may include the device light, or the conversion device light, or both. In particular, the system light may include the second light (such as one or more device lights and optionally the conversion device light) and optionally light from other light sources configured (in the light generating unit, such as in the light chamber, or outside the light generating unit). Multiple light sources may be used to provide light of different colors. Thus, the system light may have multiple wavelengths, such as multiple different colors, in an embodiment.

[0052] In an embodiment, the optical fiber may include a core comprising an optically transparent material and a cladding radially surrounding the core. In a further embodiment, the optical fiber may further include an optical outcoupling element. In particular, the cladding may radially surround the core. The optical fiber may include a core surrounded by a transparent cladding material having a lower refractive index. Furthermore, the optical fiber may include an elongated outer surface over at least a portion of its length and a cladding over at least a portion of its length, such that the optical fiber includes the elongated outer surface and the cladding along different portions of its length (such as when an opaque layer portion is configured over the cladding). This may be useful in propagating light in the optical fiber (by TIR) while simultaneously preventing any (undesired) outcoupling of light from the portion including the cladding (by the opaque outer layer). In a further embodiment, the elongated outer surface may be configured over the entire cladding. However, in an embodiment, the optical fiber may include a core and an elongated outer surface (only). In some embodiments, the optical fiber may have a core, a cladding, and an elongated outer surface (configured over the cladding). In certain embodiments, the optical fiber may also function as a waveguide.

[0053] In an embodiment, the light scattering elements may be included by the cladding. In particular, the light scattering elements may also be configured at the interface between the core and the cladding.

[0054] Moreover, in embodiments, the cladding may include a luminescent material and therefore may be luminescent in response to device light provided to the optical fiber. The luminescent material may be included by the optical fiber in embodiments such that the core of the optical fiber includes a luminescent material layer or the cladding includes the luminescent material, or a combination thereof. Thus, in certain embodiments, the cladding may include a luminescent material.

[0055] In an embodiment, the device light may include one or more of UV light and blue light. In an embodiment, the second light may be white light.

[0056] In a particular embodiment, the device light may be blue light incident on the phosphor. This may, in an embodiment, result in the emission of the converted device light by realizing an almost complete conversion of the blue light. Therefore, in an embodiment, a garnet phosphor may be used, which has a relatively high stability and thermal conductivity. However, other phosphors may also be applied. High-brightness light sources may be used in applications such as projection, stage lighting, spot lighting, and automotive lighting. For this purpose, laser phosphor technology may be used. Therefore, in an embodiment, the light-generating device may include a laser (see also above).

[0057] In an embodiment, the secondary light may be a combination of white light or may be colored light. In a further embodiment, the system light may be white light or may be colored light.

[0058] The portion of the optical fiber may, in an embodiment, have an elongated outer surface including a luminescent material capable of converting light of a wavelength different from that of the device light, i.e., the conversion device light (which may have a wavelength other than the first wavelength). In yet further embodiments, the light generating unit may include an additional light source capable of providing light of another wavelength, such as a third wavelength. Thus, the system light may include the second light (including the device light, or the conversion device light, or both) and light from the other light source.

[0059] In an embodiment, the system light provided by the light-generating system may depend on the location in the light chamber to which the second light is outcoupled. Furthermore, the system light provided by the light-generating system may depend on the number of locations to which the second light is outcoupled.

[0060] In an embodiment, the light chamber may have an internal chamber length (L3) and an internal chamber width (W3), where L2>(π×sqrt(L3×W3)). In an embodiment where the light chamber does not have a rectangular parallelepiped geometry, the chamber fiber length L2 may be configured such that L2>(2×π×A3), where A3 may be the radius of a sphere having the same volume as the light chamber. In such an embodiment, the chamber fiber length L2 may be long enough such that it may be longer than the circumference of the largest single circular loop of optical fiber that may be configured within the light chamber. A longer length of optical fiber configured within the light chamber may provide the advantage of outcoupling more light from the exit window of the light chamber.

[0061] In an embodiment, the chamber fiber length L2 may be configured such that L2≧3×(π×sqrt(L3×W3)). In an embodiment where the light chamber does not have a rectangular parallelepiped geometry, the chamber fiber length L2 may be configured such that L2>3×(2×π×A3). In such an embodiment, the chamber fiber length L2 may be long enough such that it may be longer than three times the circumference of the largest circular loop of optical fiber that may be configured within the light chamber. Thus, the optical fiber may be configured into multiple loops within the light chamber. Notably, the optical fiber may also be curved or bent at strategic locations along its length such that the chamber fiber length L2 may be accommodated within the light chamber. This may provide the advantage of accommodating a longer length of optical fiber per unit volume of the light chamber. Having more bends or bends along the optical fiber may increase the amount of second light that is outcoupled from the optical fiber.

[0062] In an embodiment, the optical fiber may have a fiber diameter (D1). In a further embodiment, the n1 bends may have a radius of curvature (Rc), where Rc<10×D1, such as Rc<9.5×D1. Furthermore, in an embodiment, D1 may be in the range of 0.1-3 mm, particularly 0.2-2.5 mm, more particularly 0.4-2.2 mm, and most particularly 0.5-2 mm.

[0063] The transmission and reflection of light propagating in an optical fiber may depend on the angle of incidence at the boundaries of the optical fiber's core. An angle of incidence greater than the critical angle for total internal reflection may cause light propagating in the optical fiber to be reflected and therefore propagate further along the optical fiber. Alternatively, light incident at an angle less than the critical angle for total internal reflection may be transmitted or outcoupled from the core of the optical fiber. Thus, device light that enters a bend contained by the optical fiber may be incident at an angle less than the critical angle for total internal reflection. Thus, in an embodiment, device light may be outcoupled from the bend in the optical fiber. The amount of light outcoupled from the optical fiber depends on the radius of curvature R of the optical fiber. c It depends on the radius of curvature of the optical fiber R c In the embodiment, the radius of curvature R c In an embodiment, the radius of curvature R of the optical fiber may be configured to be <10×D1. c may be configured such that at the curved portion 30% of the device light is outcoupled, such as particularly 50% of the device light is outcoupled, such as particularly 80% of the device light is outcoupled, such as particularly 95% of the device light is outcoupled, such as particularly 99% of the device light is outcoupled. Two or more curved portions may have the same radius of curvature or may have different radii of curvature.

[0064] Furthermore, in an embodiment, the number of bends n1 may be at least 4 or more. The bends contained by the optical fiber may therefore (also) be a source of light. The amount of system light outcoupled from the light-generating system may depend on the spatial distribution of the bends in the light chamber. Thus, in an embodiment, the optical fiber may comprise k1 bends per square centimeter, where k1≧10. For example, the optical fiber may comprise 10 bends, such as in particular 15 bends, such as in particular 20 bends, such as in particular 25 bends (where, for example, each bend is in an area of ​​5 mm×5 mm (i.e., 25 mm 2 ), such that k1 may be 40, such as in particular 60, such as in particular 80, such as in particular 100). 2 In particular, k1>2, i.e., the optical fiber may include at least three or more bends per square centimeter.

[0065] In an embodiment, the curvature may be located on a bottom surface of the light chamber (which has a reflective inner surface). In a further embodiment, the curvature may be located on (all) of the reflective inner surfaces of the light chamber. The region may in an embodiment be, for example, a region of a plane parallel to the length axis, the plane being configured within the light chamber.

[0066] In an embodiment, the curvatures may be (uniformly) distributed in the light chamber in a 2D (or 3D; see also below) spatial arrangement. In particular, the curvatures may be arranged such that the area (Ai) of a Voronoi cell from the 2D Voronoi tessellation of a region containing the projection of the curvatures may be selected from the range of 0.7 to 1.3 times, such as in particular 0.8 to 1.2 times, such as in particular 0.9 to 1.1 times the average area of ​​all Voronoi cells in the 2D Voronoi tessellation. Voronoi tessellations (or "Voronoi diagrams") are known in the art. See: Aurenhammer, Franz (1991). "Voronoi Diagrams - A Survey of a Fundamental Geometric Data Structure", ACM Computing Surveys. 23 (3):345-405, doi:10.1145 / 116873.116880. S2CID 4613674, or Skyum, Sven (18 February 1991). "A simple algorithm for computing the smallest enclosing circle", Information Processing Letters, 37 (3):121-125. doi:10.1016 / 0020-0190(91)90030-L. (including an algorithm for computing the farthest-point Voronoi diagram); the documents incorporated herein by reference describe Voronoi tessellations and algorithms for generating them.

[0067] A 2D Voronoi tessellation refers to the division of a planar region into a subset of regions (or Voronoi cells) where each Voronoi cell encloses a single curvature, but in such a way that any location within the Voronoi cell is closer to that curvature than any other curvature. For example, a light chamber that includes clustered or aggregated curvatures in any portion of the light chamber will include a Voronoi cell that has an area smaller than the average area of ​​all Voronoi cells in the 2D Voronoi tessellation. Similarly, curvatures that are spaced apart from one another may constitute a Voronoi cell that is larger than the average area of ​​all Voronoi cells in the tessellation. Therefore, the variance of the Voronoi cells with respect to the average area of ​​all Voronoi cells in the 2D Voronoi tessellation can be an indication of how evenly the curvatures are distributed within a region (such as within a light chamber). Thus, in an embodiment, the curvatures may be uniformly arranged (or uniformly distributed) such that a Voronoi cell comprising the curvature has an area (Ai) selected from the range of 0.7 to 1.3 times, such as in particular 0.8 to 1.2 times, such as in particular 0.9 to 1.1 times, of the average area of ​​all Voronoi cells in the 2D Voronoi tessellation. In an embodiment, the curvatures may be distributed within the volume constituted by the optical chamber such that the area of ​​a Voronoi cell (in a projection (along a particular orientation) of the curvatures) has an area Ai selected from the range of 0.7 to 1.3 times, such as in particular 0.8 to 1.2 times, such as in particular 0.9 to 1.1 times, of the average area of ​​all (projected) Voronoi cells in the 2D Voronoi tessellation.

[0068] In an embodiment, the curvatures may be essentially arranged in a 3D configuration such that they are uniformly distributed. Similar to the 2D Voronoi tessellation, the 3D Voronoi tessellation refers to the division of the volume into a subset of volumes (or Voronoi cells) where each Voronoi cell encloses a single curvature, but in such a way that any location within a Voronoi cell is closer to that curvature than any other curvature. In particular, the curvatures may be distributed in a 3D configuration or arrangement such that the curvatures are uniformly distributed within the light chamber. Thus, in an embodiment, the curvatures may be arranged such that the volume (Vi) of a Voronoi cell from the 3D Voronoi tessellation of a volume containing a curvature may be selected from the range of 0.7 to 1.3 times, such as in particular 0.8 to 1.2 times, such as in particular 0.9 to 1.1 times, of the average volume of all Voronoi cells in the 3D Voronoi tessellation.

[0069] In an embodiment, (a portion of) the optical fiber (within the light chamber) may be configured in a serpentine configuration. In particular, the optical fiber may follow a serpentine path that includes one or more U-shaped turns. A U-shaped turn (also U-shaped bend or U-shaped corner) is a bend in the path that has a very sharp internal angle, such that the propagating light must turn back approximately 180° to continue along the optical fiber. Hence, the bend may exhibit a U-shaped turn.

[0070] In embodiments, the serpentine configuration may have at least 3 folds, particularly at least 6 folds, more particularly at least 8 folds, and even more particularly at least 10 folds. For example, in embodiments, the optical fiber may have between 3 and 100 folds with optical chambers, such as particularly at least about 12 folds, such as at least 20 folds.

[0071] In an embodiment, the optical fiber may be arranged in a stacked configuration (within the optical chamber). Furthermore, the optical fiber may be arranged in a 3D configuration by stacking one or more 2D configurations. That is, in an embodiment, the optical fiber may be arranged in a 2D configuration and several such configurations may be stacked to arrive at a 3D stacked configuration using a single optical fiber. In a further embodiment, these stacks may be stacked such that each 2D planar configuration within the stack is rotated by an angle of 30°, for example 60°, for example 90°, for example 120°, for example 180°, compared to the previous stack.

[0072] In embodiments, the optical fiber may be arranged (within the light chamber) in a spiral configuration. In particular, the optical fiber may take a winding path that describes a series of gradually expanding (or contracting) curves about a center point on a flat surface (such as a reflective inner surface of the light chamber) or about an axis to form a cone. Furthermore, in embodiments, the optical fiber may be arranged in a helix shape. Furthermore, the optical fiber may be arranged (within the light chamber) in an arrangement such as a corkscrew or a spiral staircase.

[0073] In an embodiment, the spiral configuration may have at least 3 turns, in particular at least 6 turns, more particularly at least 8 turns, more particularly at least 10 turns. In an embodiment, a single light chamber may include 50 turns or less, for example 25 turns or less. However, other values ​​may also be possible.

[0074] Further, in embodiments, the optical fibers may be arranged (within the light chamber) in an interleaved configuration. In particular, the optical fibers may be arranged in alternating layers. In embodiments, the optical fibers may be arranged within the light chamber such that the optical fibers may be curved on themselves. Further, the optical fibers may be arranged in one or more 2D configurations in which the planar arrangements of the optical fibers are interleaved, in embodiments, where interleaving may refer to alternating portions of the optical fibers being arranged on top of each other.

[0075] In an embodiment, a portion of the optical fiber may (also) be arranged outside the light chamber. During operation of the light-generating device, at least a portion of the second light may exit the optical fiber outside the light chamber. In particular, at least a portion of the optical fiber may be arranged outside the light-generating unit. In an embodiment, the optical fiber may have an elongated outer surface on at least a portion of the optical fiber that is arranged outside the light chamber.

[0076] In further embodiments, the optical fiber may include a cladding on at least a portion of the optical fiber that is configured outside the light chamber. In particular, the optical fiber may be configured to outcouple the second light from at least a portion of the optical fiber that is configured outside the light chamber.

[0077] In an embodiment, the light-generating system may comprise a plurality of light-generating units. In a further embodiment, at least two light-generating units may share a portion of the same optical fiber. In particular, the light-generating system may comprise a single optical fiber that can enter and exit a first light-generating unit, and the same optical fiber may enter and exit a second light-generating unit. Each light-generating unit may comprise a light chamber. Within each light chamber, the optical fiber may comprise a plurality of bends (see also above).

[0078] Similarly, in an embodiment, the same optical fiber may be routed through multiple light-generating units. Thus, the multiple light-generating units may be configured to provide the system light. In an embodiment, the light-generating system may comprise N light-generating units, where N may be at least 3, particularly at least 4, more particularly at least 5, and most particularly at least 6. Furthermore, the optical fiber may include at least a portion configured outside the first light-generating unit and the second light-generating unit, and the optical fiber may be configured to outcouple the second light from at least a portion of the optical fiber configured outside the first light-generating unit and the second light-generating unit. In an embodiment, the optical fiber may outcouple the second light in at least a portion of the optical fiber configured outside the multiple light-generating units.

[0079] The light-generating system comprises two or more optical fibers and two or more light-generating devices, each of which is composed of two or more sets of optical fibers and one or more light-generating devices, and the light entrance is arranged downstream of the one or more light-generating devices. Thus, the light entrance of the optical fiber entering the subsequent light-generating unit may be arranged downstream of the light-generating device (which supplies the optical fiber with device light). Furthermore, in an embodiment, the light-generating system may comprise multiple sets of optical fibers and one or more light-generating devices, each of which is composed of two or more sets of optical fibers and one or more light-generating devices.

[0080] Thus, a single light chamber may house at least a portion of two (or more) different optical fibers that may receive the device light of two (or more) different light-generating devices. In this manner, more secondary light may be generated and / or secondary light having different spectral power distributions may be generated.

[0081] The spectral power distribution of the second light of two or more optical fibers is different. In an embodiment, the spectral power distribution of the system light outcoupled from each set (comprising one or more light-generating devices) may depend on the spectral power distribution of the second light outcoupled from the optical fibers included by that set. Thus, each set may have a different spectral power distribution of the outcoupled system light or the second light outcoupled from at least a portion of the optical fibers configured external to the light-generating unit, or a combination thereof. In an embodiment, the light-generating system may be configured such that the spectral power distribution of the system light can be changed by changing the spectral power of the second light outcoupled from two or more of the optical fibers.

[0082] In an embodiment, the light-producing system may comprise one or more solid-state light sources for supplying device light to one or more optical fibers, such that the spectral power distribution of one or more optical fibers may be varied by varying the spectral power distribution of the corresponding one or more solid-state light sources.

[0083] Furthermore, the color of the system light (including at least a portion of the second light) may be changed by varying the wavelength and intensity of the device light provided to one or more optical fibers.

[0084] The light-generating system further comprises a control system configured to control the spectral power distribution of the system light, for example by controlling the wavelength and intensity of the light provided by the light-generating device.

[0085] In further embodiments, the system light may include at least a portion of a second light of one or more optical fibers that exits the one or more light chambers through one or more chamber exit windows.

[0086] In certain embodiments, the control system may be configured to control one or more of the color rendering index (CRI), correlated color temperature (CCT), and color point of the system light.

[0087] In an embodiment, the light chamber may have a cross-sectional shape selected from the group of circular, elliptical, rectangular, and n-sided, where n is at least 5. Here, n-sided may refer to a regular polygon (i.e., a polygon with sides of equal length) having n sides, such as at least 5. In a further embodiment, the light chamber may have a 3D geometric shape, such as a sphere, or a dome, or a polyhedron. In particular, the light chamber may have a geometric shape that is a combination of one or more of the aforementioned geometric shapes. In an alternative embodiment, the light chamber may have an oblate or prolate spheroid geometric shape.

[0088] In an embodiment, the chamber exit window may include a diffuser for the second light. The diffuser may be a semi-transparent or semi-transparent cover that diffuses or scatters the light. Thus, the brightness of the system light provided may be controlled by the diffuser. The diffuser may further provide the advantage of providing soft light, i.e., scattered light as opposed to a light beam. Furthermore, in an embodiment, the chamber exit window may include a luminescent material or a color filter. In an embodiment, the reflective inner surface of the light chamber may be diffusely reflective. Here, diffuse reflectivity refers to the reflection of light from a surface such that a ray of light incident on the surface is scattered at many angles, rather than a single angle as in the case of specular reflection. Thus, in an embodiment, the light generating system may provide diffuse system light. In a further embodiment, the light generating system may include an optical fiber including a diffuser configured radially around the optical fiber, or a light chamber having a reflective inner surface that is diffusely reflective, or both.

[0089] The light generating system may be part of or applied to, for example, an office lighting system, a home application system, a store lighting system, a household lighting system, an accent lighting system, a spot lighting system, a theater lighting system, a fiber optic application system, a projection system, a self-illuminated display system, a pixelated display system, a segmented display system, a warning sign system, a medical lighting application system, an indicator sign system, a decorative lighting system, a portable system, an automotive application, an (outdoor) road lighting system, an urban lighting system, a greenhouse lighting system, a horticultural lighting, a digital projection, or an LCD backlight. The light generating system (or luminaire) may be part of or applied to, for example, an optical communication system or a disinfection system. As mentioned above, the lighting unit may be used as a backlight unit in an LCD display device. Therefore, the present invention also provides an LCD display device comprising a lighting generating system as defined herein configured as a backlight unit. The present invention also provides, in a further aspect, a liquid crystal display device comprising a backlight unit, the backlight unit comprising one or more light generating systems as defined herein.

[0090] In yet a further aspect, the present invention may also provide a lamp or luminaire comprising a light-generating system as defined herein. The luminaire may further comprise a housing, optical elements, louvers, etc. The lamp or luminaire may further comprise a housing enclosing the light-generating system. The lamp or luminaire may comprise an optical window in the housing, or a housing opening through which the system light may escape the housing. In yet a further aspect, the present invention also provides a projection device comprising a light-generating system as defined herein. In particular, a projection device or "projector" or "image projector" may be an optical device that projects an image (or a moving image) onto a surface, such as a projection screen. The projection device may include one or more light-generating systems as described herein. Thus, in one aspect, the present invention also provides a light-generating device selected from the group of a lamp, a luminaire, a projector device, a disinfection device, a photochemical reactor, and an optical wireless communication device, comprising a light-generating system as defined herein. The light-generating device may comprise a housing or support configured to accommodate or support one or more elements of the light-generating system. For example, in embodiments the light-generating devices may comprise a housing or support configured to house or support one or more of the light-generating devices.

[0091] The phrase "light having one or more wavelengths in a wavelength range" and similar phrases may specifically indicate that the light (or radiation) has a spectral power distribution that has at least an intensity at one or more of the wavelengths in the wavelength range indicated. For example, a blue-emitting solid-state light source will have a spectral power distribution that has an intensity at one or more wavelengths in the wavelength range of 440-495 nm.

[0092] The phrases 2D or "2-D" or "two-dimensional", in embodiments, may refer to an object (or structure or solid) that has only two dimensions, such as length and width, and no thickness or height. The phrases 3D or "3-D" or "three-dimensional", in embodiments, may refer to an object (or structure or solid) that has three dimensions, including length, depth, and width.

[0093] The phrases "different light sources" or "multiple different light sources" and similar phrases may, in embodiments, refer to multiple solid-state light sources selected from at least two different bins. Similarly, the phrases "same light source" or "multiple identical light sources" and similar phrases may, in embodiments, refer to multiple solid-state light sources selected from the same bin.

[0094] The terms "upstream" and "downstream" refer to the positioning of an article or feature relative to the propagation of light from a light generating means (here specifically a light generating device), where relative to a first position in the light beam from the light generating means, a second position in the light beam that is closer to the light generating means is "upstream" and a third position in the light beam that is farther away from the light generating means is "downstream".

[0095] The term "visible light" particularly relates to light having a wavelength selected from the range of 380-780 nm. UV (ultraviolet light) may in this specification refer in particular to a wavelength selected from the range of 190-380 nm, although in certain embodiments other wavelengths may also be possible. IR (infrared light) may in this specification refer in particular to radiation having a wavelength selected from the range of 780-3000 nm, for example 780-2000 nm, for example up to about 1500 nm, such as a wavelength of at least 900 nm, although in certain embodiments other wavelengths may also be possible. Thus, the term IR may in this specification refer to one or more of near infrared (NIR (or IR-A)) and short wavelength infrared (SWIR (or IR-B)), in particular NIR. The term "white light" and similar terms in this specification are known to those skilled in the art. White light may in particular relate to light having a correlated color temperature (CCT) in the range of approximately 1800K to 20000K, for example 2000 to 20000K, in particular 2700 to 20000K, and for general lighting in particular in the range of approximately 2000 to 7000K, for example 2700K to 6500K.

[0096] In embodiments, for example, for backlighting purposes or for other purposes, the correlated color temperature (CCT) may be in particular in the range of about 7000K to 20000K. Still further, in embodiments, the correlated color temperature (CCT) may be in particular within about 15 SDCM (standard deviation of color matching) from the BBL (black body locus), in particular within about 10 SDCM from the BBL, and even more particularly within about 5 SDCM from the BBL. In particular embodiments, the correlated color temperature (CCT) may be selected from the range of 6000 to 12000K, such as from the range of 7000 to 12000K, for example at least 8000K. Still further, in embodiments, the correlated color temperature (CCT) may be selected from the range of 6000 to 12000K, such as from the range of 7000 to 12000K, in combination with a CRI of at least 70. In one embodiment, the light source may also provide source light with a correlated color temperature (CCT) of about 5000-20000K, for example a direct phosphor converted LED (e.g. a blue light emitting diode with a thin layer of phosphor to obtain 10000K). Thus, in a particular embodiment, the solid state light source may be configured to provide light with a correlated color temperature in the range of 5000-20000K, even more particularly in the range of 6000-20000K, for example 8000-20000K. An advantage of a relatively high color temperature may be that there may be a relatively high blue content in the source light.

[0097] The term "controlling" and similar terms in particular refer to at least determining the behavior of an element or managing the operation of an element. Thus, in this specification, "controlling" and similar terms may refer to, for example, imposing a behavior on an element (determining the behavior of an element or managing the operation of an element), such as, for example, measuring, indicating, activating, opening, transitioning, changing temperature, etc. Alternatively, the term "controlling" and similar terms may further include monitoring. Thus, the term "controlling" and similar terms may include imposing a behavior on an element, as well as imposing a behavior on an element and monitoring the element. Controlling an element can be performed by a control system, which may also be denoted as a "controller". Thus, the control system and the element may be functionally coupled, at least temporarily, or permanently. The element may include the control system. In an embodiment, the control system and the element may not be physically coupled.

[0098] The control can be via wired control and / or wireless control. The term "control system" may also refer to a number of different control systems, in particular functionally coupled, of which for example one control system may be a master control system and one or more other control systems may be slave control systems. The control system may include a user interface or be functionally coupled to a user interface. The control system may also be configured to receive and execute instructions from a remote controller. In an embodiment, the control system may be controlled via an app on a device, such as a portable device, such as a smartphone or an I-phone, a tablet, etc. Thus, the device may not necessarily be coupled to the lighting system, but may be functionally coupled (temporarily) to the lighting system. Thus, in an embodiment, the control system may (also) be configured to be controlled by an app on a remote device. In such an embodiment, the control system of the lighting system may be a slave control system or may control in a slave mode. For example, the lighting system may be identifiable by a code, in particular a unique code related to the corresponding lighting system. The control system of the lighting system may be configured to be controlled by an external control system, which has access to the lighting system based on knowledge of the (unique) code (entered by a user interface of an optical sensor (e.g. a QR code reader)).

[0099] The lighting system may also comprise means for communicating with other systems or devices, such as based on Bluetooth, WIFI, LiFi, ZigBee, BLE, or WiMAX, or another wireless technology. The system, or the apparatus, or the device may perform an action in a "mode" or "operation mode". The term "operation mode" may also be indicated as a "control mode". Similarly, in a method, an action, or a phase, or a step may be performed in a "mode" or "operation mode". This does not exclude that the system, or the apparatus, or the device may also be adapted to provide another control mode, or multiple other control modes. Similarly, this may not exclude that one or more other modes may be performed before and / or after performing a mode. However, in an embodiment, a control system adapted to provide at least a control mode may be available. If other modes are available, the selection of such modes may in particular be performed via a user interface, although other options may also be possible, such as executing the mode in response to a sensor signal or a (time) scheme. An operational mode may also refer in embodiments to a system, or an apparatus, or a device that can only operate in a single operational mode (i.e., "on", without further adjustability). Thus, in embodiments, the control system may control in response to one or more of a user interface input signal, a (sensor) sensor signal, and a timer. The term "timer" may refer to a clock and / or a predefined time scheme. [Brief description of the drawings]

[0100] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, and in which: [Figure 1A] 1 illustrates a schematic representation of an embodiment of a light-generating system 1000 in which an optical fiber 500 is arranged within a light-generating unit 1400 . [Figure 1B] 1 illustrates a schematic representation of an embodiment of a light-generating system 1000 in which an optical fiber 500 is arranged within a light-generating unit 1400 . [Figure 2A] 1 illustrates generally an embodiment of a light-generating system 1000 comprising a set of one or more optical fibers 500 and one or more light-generating units 1400 arranged along each optical fiber 500 . [Figure 2B] 1 illustrates generally an embodiment of a light-generating system 1000 comprising a set of one or more optical fibers 500 and one or more light-generating units 1400 arranged along each optical fiber 500 . [Figure 2C] 1 illustrates generally an embodiment of a light-generating system 1000 comprising a set of one or more optical fibers 500 and one or more light-generating units 1400 arranged along each optical fiber 500 . [Diagram 3] 12 illustrates a schematic representation of an embodiment of a lighting device 1200.

[0101] The schematic drawings are not necessarily to scale. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0102] FIG. 1A shows a schematic representation of an embodiment of a light-generating system 1000, which may comprise a light-generating device 100, an optical fiber 500, and a light-generating unit 1400. In particular, the light-generating device 100 may be configured to generate a device light 101 having a first wavelength. In an embodiment, the light-generating device 100 may comprise a solid-state light source. Furthermore, the optical fiber 500 may comprise an elongated body of an optically transparent material that is transparent to the device light 101 having the first wavelength. In an embodiment, the optical fiber 500 may comprise a core 502 comprising an optically transparent material and a cladding 503 radially surrounding the core 502, and the optical fiber further comprises an optical outcoupling element 510. In particular, the optical fiber 500 may comprise an optical input portion 511. In an embodiment, the optical fiber 500 may have a length L1 and an elongated outer surface 512 over at least a portion of the length L1. Furthermore, the optical fiber 500 may be configured such that when the device light 101 having the first wavelength is irradiated to the light input 511, the second light 501 exits the optical fiber 500 through the elongated outer surface 512 over at least a portion of its length L1. Specifically, in an embodiment, the optical fiber 500 may include a luminescent material 200 configured to convert at least a portion of the device light 101 into the converted device light 201. In an embodiment, the light generation unit 1400 may include a light chamber 400. Furthermore, the light chamber 400 may have a reflective inner surface 410 and be reflective to the second light 501. In an embodiment, the light generation system 1000 may include n1 bends 550, where n1≧4. Furthermore, in an embodiment, the light generation system 1000 may include k1 bends 550 per square centimeter, where k1≧10. The bends 550 may in certain embodiments be arranged such that the area (Ai) of a Voronoi cell from the 2D Voronoi tessellation of a region including the projection of the bends 550 is selected in the range of 0.7-1.3 times, such as in particular 0.8-1.2 times, such as in particular 0.9-1.1 times the average area of ​​all Voronoi cells in the 2D Voronoi tessellation. The figure further shows two embodiments of a light-generating system including 12 bends (left) and 20 bends (right).The irradiance of the light-generating system can vary depending on the number of bends provided and where they are located within the light-generating unit. The irradiance of two embodiments of a rectangular light-generating unit (viewed from above) is provided: one with 12 bends and one with 20 bends. The coordinate axes represent the physical dimensions of the light-generating unit, i.e. along the length and width, and the colors are in W / mm. 2 The unit of irradiance is expressed as

[0103] FIG. 1B shows a schematic diagram of an embodiment of a light-generating system 1000, which may include a light-generating device 100, an optical fiber 500, and a light-generating unit 1400. In particular, the light-generating device 100 may be configured to generate a device light 101 having a first wavelength, and in an embodiment, the light-generating device 100 may include a solid-state light source. Furthermore, the optical fiber 500 may include an elongated body of a light-transmitting material that is transparent to the device light 101 having the first wavelength. In an embodiment, the optical fiber 500 may include a light entrance 511. Furthermore, in an embodiment, the optical fiber 500 may have a length L1 and an elongated outer surface 512 over at least a portion of the length L1. In particular, the optical fiber 500 may be configured such that, when the device light 101 having the first wavelength is irradiated onto the light entrance 511, the second light 501 exits the optical fiber 500 through the elongated outer surface 512 over at least a portion of the length L1. Furthermore, the light generating unit 1400 may include a light chamber 400. In an embodiment, the light chamber 400 may have a reflective inner surface 410 that is reflective to the second light 501 and a chamber exit window 420 that is transparent to the second light 501. In particular, at least a portion of the optical fiber 500 having a chamber fiber length L2 may be configured to have n1 bends 550 in a plane parallel to the length axis (A) of the optical fiber 500 within the light chamber 400, where n1≧1. In an embodiment, the light generating system 1000 may be configured to generate a system light 1001 that includes at least a portion of the second light 501 that exits the light chamber 400 through the chamber exit window 420. Furthermore, in an embodiment, the solid-state light source may include a laser. In particular, the solid-state light source may include a diode laser. In a particular embodiment, the device light 101 may include a diode laser light. Moreover, the system light 1001 may, in embodiments, include one or more of the device light 101 and the converted device light 201. In particular, the optical fiber 500 may include a luminescent material 200 configured to convert at least a portion of the device light 101 to the converted device light 201. In further embodiments, the cladding may include the luminescent material 200.The device light 101 may specifically include one or more of UV light and blue light, and the system light 1001 is white light. In an embodiment, the light chamber 400 may have an inner chamber length (L3) and an inner chamber width (W3), where L2>(π×sqrt(L3×W3)). In a further embodiment, L2≧2×(π×sqrt(L3×W3)). In an embodiment, the optical fiber 500 may have a fiber diameter (D1), and the n1 bends 550 have a radius of curvature (Rc), where Rc<10×D1. In a further embodiment, the light generation system 1000 may include n1 bends 550, where n1≧4. In an embodiment, the light generation system 1000 may include k1 bends 550 per square centimeter, where k1≧10. In particular, in an embodiment, the curved portion 550 may be positioned such that the area (Ai) of a Voronoi cell from the 2D Voronoi tessellation in a region including the projection of the curved portion 550 is selected from the range of 0.7 to 1.3 times, such as in particular 0.8 to 1.2 times, such as in particular 0.9 to 1.1 times the average area of ​​all Voronoi cells in the 2D Voronoi tessellation.

[0104] FIG. 2A shows a schematic diagram of an embodiment of a light-generating system. In this embodiment, a portion of the optical fiber 500 may be arranged outside the light chamber 400. In particular, during operation of the light-generating device 100, a portion of the second light 501 may exit the optical fiber outside the light chamber 400. In an embodiment, the system light 1001 may include a portion of the second light 501. The figure shows two light-generating units 1400 arranged along a single optical fiber 500. In particular, a portion of the optical fiber 500 between the two light-generating units (i.e., outside the light-generating units) may be arranged to provide the second light 501. In an embodiment, multiple light-generating units 1400 of the light-generating system may share a portion of the same optical fiber 500.

[0105] FIG. 2B shows a schematic diagram of an embodiment of a light-generating system. In an embodiment, the light-generating system 1000 may comprise two or more optical fibers 500 and two or more light-generating devices 100, each configured in two or more sets of optical fibers 500 and one or more light-generating devices 500. The figure shows an embodiment with three optical fibers, with two light-generating units configured on the first optical fiber and the third optical fiber, and three light-generating units configured on the second optical fiber. Thus, in an embodiment, the light entrance 511 may be configured downstream of these one or more light-generating devices 100. In particular, the spectral power distribution of the second light 501 of the two or more optical fibers 500 may be different. In a particular embodiment, the light-generating system 1000 may further comprise a control system 300 configured to control the spectral power distribution of the system light 1001. In particular, the system light 1001 may include at least a portion of the second light 501 of one or more optical fibers 500 that exits the one or more light chambers 400 through one or more chamber exit windows 420 .

[0106] FIG. 2C shows a schematic of an embodiment of a light-generating system. In an embodiment, the optical fiber 500 may be arranged in one or more of a serpentine configuration, a stacked configuration, a spiral configuration, and an interleaved configuration. Furthermore, in an embodiment, the light chamber 400 may have a cross-sectional shape selected from the group of a circle, an ellipse, a rectangle, and an n-sided shape, where n is at least 5. In an embodiment, the chamber exit window 420 may include a diffuser for the second light 501. In particular, the reflective inner surface 410 is diffusely reflective. In the depiction of the embodiment in the figure, one of the light-generating units 1400 has a circular cross-sectional shape in which the optical fiber 500 is arranged in a serpentine configuration. In an embodiment, another light-generating unit 1400 has an elliptical cross-sectional shape in which the optical fiber 500 is arranged in a spiral configuration. In an embodiment, yet another light-generating unit 1400 has a hexagonal cross-sectional shape in which the optical fiber has a stacked configuration.

[0107] Fig. 3 shows a schematic representation of an embodiment of a lighting device 1200. In an embodiment, the lighting device 1200 may be selected from the group of a lamp 1, a luminaire 2, a projector device 3, a disinfection device, a photochemical reactor, and an optical wireless communication device, comprising a light-generating system 1000 as described herein. Reference number 301 indicates a user interface, which may be functionally coupled to a control system 300 included by or functionally coupled to the light-generating system 1000. Fig. 3 also shows a schematic representation of an embodiment of a lamp 1, comprising a light-generating system 1000. Reference number 3 indicates a projector device or projector system, which may be used to project an image on a wall or the like, which may also comprise the light-generating system 1000. In an embodiment, such a lighting device may be a lamp 1, a luminaire 2, a projector device 3, a disinfection device, or an optical wireless communication device. The lighting device light exiting the lighting device 1200 is indicated with reference number 1201. The illumination device light 1201 may consist essentially of the system light 1001, and therefore may be the system light 1001 in certain embodiments.

[0108] The term "plurality" refers to two or more.

[0109] 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", "all", etc. Thus, in embodiments, the adjectives substantially or essentially may also be omitted. Where applicable, the terms "substantially" or "essentially" may also relate to 90% or more, including 100%, such as 95% or more, particularly 99% or more, and even more particularly 99.5% or more.

[0110] The term "comprise" also includes embodiments in which the term "comprises" means "consists of". The term "and / or" specifically relates to one or more of the items mentioned before and after "and / or". For example, the phrase "item 1 and / or item 2" and similar phrases may relate to one or more of items 1 and 2. The term "comprising" may refer to "consisting of" in one embodiment, but may also refer to "including at least the species defined, and optionally one or more other species" in another embodiment. Furthermore, the terms first, second, third, etc. in the specification and claims are used to distinguish between similar elements and are not necessarily used to describe a sequential or chronological order. It is to 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 those described or illustrated herein.

[0111] In this specification, a device, apparatus, or system may be described, inter alia, in operation. As will be apparent to one skilled in the art, the present invention is not limited to methods of operation or to devices, apparatus, or systems in operation. It should be noted that the above-described embodiments are illustrative rather than limiting of the present invention, and that one skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims.

[0112] In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. Use of the verb "to comprise" and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. Unless the context clearly requires otherwise, throughout the specification and claims, the words "comprise", "comprising" and the like are to be interpreted in an inclusive sense, i.e., "including, but not limited to", rather than an exclusive or exhaustive sense.

[0113] The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

[0114] The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In a device claim, or an apparatus claim, or a system claim enumerating several means, several of these means may be embodied by one and the same item of hardware. The mere fact that certain means are recited in mutually different dependent claims does not indicate that a combination of these means cannot be used to advantage. In still a further aspect, the invention therefore provides a software product which, when executed on a computer, is capable of causing (one or more embodiments of) the method as described herein.

[0115] The present invention also provides a control system that may control a device, apparatus or system or that may perform the methods or processes described herein. Still further, the present invention also provides a computer program product that, when executed on a computer operatively coupled to or included by a device, apparatus or system, controls one or more controllable elements of such a device, apparatus or system.

[0116] The invention further applies to a device, an apparatus or a system comprising one or more of the features described in the present specification and / or shown in the accompanying drawings.The invention further relates to a method or process comprising one or more of the features described in the present specification and / or shown in the accompanying drawings.

[0117] The various aspects discussed in this patent may be combined to provide additional advantages. Moreover, those skilled in the art will appreciate that embodiments may be combined, and that three or more embodiments may be combined. Moreover, some of the features may form the basis for one or more divisional applications.

[0118] Among other things, a (laser) illumination system is proposed herein, comprising a laser light source and an optical fiber having a core and a clad. The laser light source emits laser light, which can be incoupled to the light guide at a light incoupling section. The incoupled light can be transported through the optical fiber via total internal reflection. The core and / or the clad may include a light outcoupling means for coupling out the TIR light out of the optical fiber (e.g. using scattering particles in the clad that are in physical contact with the core and extract the light accordingly). A portion of the optical fiber may be arranged in a light mixing chamber, which has one or more light diffusing surfaces. To obtain uniform illumination from one or more light diffusing surfaces, the portion of the optical fiber arranged in the light mixing chamber may be arranged, for example, in a serpentine and / or spiral configuration. At the shaped loops in the spiral and at the bends of the serpentine, additional light may exit the optical fiber and contribute to a higher intensity at the diffusing surface.

[0119] The light mixing chamber may have a meander / spiral shaped groove in which the optical fiber may be placed. In the case of a spiral configuration, the distance between adjacent optical fiber portions may decrease with increasing diameter of the spiral. In the case of a serpentine configuration, adjacent fiber portions in the bend area may be placed at a greater distance than adjacent fiber portions in other areas. Alternatively, or in addition, the bends may be arranged in a distributed manner. The light diffusing surface may have a reflectivity in the range of 20-40% in embodiments. To increase the light intensity at the light diffusing surface, the spiral or meander areas may be stacked, preferably interleaved. The pattern of the optical fiber may be selected to obtain "complementary" illumination patterns that can be used in a stacked configuration. The light mixing chamber may typically have (>80%) light reflective walls to direct the light towards the user.

[0120] Therefore, among other things, the present invention provides a laser illumination system in which portions of optical fibers may be arranged in a serpentine or spiral configuration within one or more light-mixing chambers.

Claims

1. A light-generating system comprising a light-generating device, an optical fiber, and a light-generating unit, the light-generating device is configured to generate device light having a first wavelength, the light-generating device including a solid-state light source; the optical fiber includes an elongated body of a light-transmitting material that is transparent to the device light having the first wavelength, the optical fiber includes a light entrance portion, the optical fiber has a length L1 and an elongated outer surface over at least a portion of the length L1 of the optical fiber, and the optical fiber is configured such that, when the device light having the first wavelength is irradiated onto the light entrance portion, a second light exits the optical fiber via the elongated outer surface over at least a portion of the length L1 of the optical fiber; the light generating unit includes a light chamber having a reflective inner surface reflective to the second light and a chamber exit window transmissive to the second light; at least a portion of the optical fiber having a chamber fiber length L2 is configured to have n1 bends in a plane parallel to a length axis of the optical fiber within the optical chamber, where n1≧1; the light-producing system is configured to produce a system light that includes at least a portion of the second light; the light-generation system comprising two or more optical fibers and two or more light-generating devices, each configured with two or more sets of optical fibers and one or more light-generating devices, the light entrance configured downstream of the one or more light-generating devices, the second light of the two or more optical fibers having different spectral power distributions, the light-generation system further comprising a control system configured to control the spectral power distribution of the system light, the system light comprising at least a portion of the second light of one or more optical fibers.

2. The light production system of claim 1 , wherein the solid-state light source comprises a laser.

3. the solid-state light source comprises a diode laser, the device light comprises a diode laser light, and the system light comprises Device light and and a conversion device light, wherein the optical fiber comprises a luminescent material configured to convert at least a portion of the device light into the conversion device light.

4. 4. The light generating system of claim 3, wherein the optical fiber comprises a core comprising the optically transparent material and a cladding surrounding the core, the optical fiber further comprises a light outcoupling element, the cladding comprising the luminescent material, the device light comprises one or more of UV light and blue light, and the system light is white light.

5. 5. The light generation system of claim 1, wherein the light chamber has an inner chamber length L3 and an inner chamber width W3, where L2>(π×sqrt(L3×W3)).

6. 6. The light-generating system of claim 5, wherein L2 >= 3*(π*sqrt(L3*W3)).

7. 7. The light-generating system of claim 1, wherein the optical fiber has a fiber diameter D1 and the n1 bends have a radius of curvature Rc, where Rc<10*D1.

8. 8. The light production system of claim 7, comprising k1 bends per square centimeter, where k1 > 10.

9. 9. The light generation system of claim 7 or 8, wherein the curvature is arranged such that the area Ai of a Voronoi cell from a 2D Voronoi tessellation in a region containing a projection of the curvature is selected from the range of 0.7 to 1.3 times the average area of ​​all Voronoi cells in the 2D Voronoi tessellation.

10. 10. The light-producing system of any one of the preceding claims, wherein the optical fibers are arranged in one or more of a serpentine configuration, a stacked configuration, a spiral configuration, and an interleaved configuration.

11. 11. The light-generating system of claim 1, wherein a portion of the optical fiber is configured outside the light chamber, and during operation of the light-generating device, at least a portion of the second light exits the optical fiber outside the light chamber.

12. 12. A light-generating system according to any one of the preceding claims, comprising a plurality of light-generating units, at least two of the light-generating units sharing the same optical fibre.

13. 13. The light-generating system of claim 1, comprising two or more optical fibers and two or more light-generating devices, each configured with two or more sets of optical fibers and one light-generating device, the light entrance configured downstream of the one or more light-generating devices, the second light of the two or more optical fibers having different spectral power distributions, the light-generating system further comprising a control system configured to control the spectral power distribution of the system light, the system light comprising at least a portion of the second light of one or more optical fibers.

14. 14. The light generation system of claim 1, wherein the light chamber has a cross-sectional shape selected from the group consisting of circular, elliptical, rectangular, and n-sided, where n is at least 5, the chamber exit window comprises a diffuser for the second light, and the reflective inner surface is diffusely reflective.

15. A lighting device selected from the group of lamps and luminaires, comprising a light production system according to any one of the preceding claims.

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