Cloud for artificial sunroofs and windows

Abstract

The invention provides a light generating system (1000) comprising a housing unit (400), a first light generating device (110) and one or more objects (440) wherein: the first light generating device (110) is configured to generate first device light (111) comprising visible light wherein the visible light comprises at least blue light; the shell unit (400) comprises a shell wall (420) and a shell window (430) which are used for sealing the shell space (410); wherein the housing wall (420) is configured to absorb at least a portion of the first device light (111) reaching the housing wall (420); and wherein the housing window (420) is translucent to the first device light (111) and scatters at least a portion of the blue light; the first light generating device (110) and the housing unit (400) are configured such that (i) the first device light (111) is provided in the housing space (410) and (ii) a portion of the first device light (111) escapes from the housing space (410) via the housing window (430); one or more objects (440) disposed in the housing space (410) and configured to reflect at least a portion of the first device light (111) reaching the one or more objects (440); the housing unit (400), the first light generating device (110) and the one or more objects (440) are configured such that at least a portion of the first device light (111) reaching the one or more objects (440) reaches the one or more objects only via reflection at the housing window (430).

Description

Technical Field

[0001] The invention relates to a light generating system, for example for providing artificial daylight. The invention also relates to a space comprising a light generating system, for example for providing artificial daylight. Background Art

[0002] Systems for generating artificial daylight are known in the art. For example, WO2014076656A1 describes a lighting system for illuminating an environment using lighting that simulates natural lighting, comprising: a first light source that emits a visible light beam; a diffuse light generator defined by an inner surface that receives the light beam and an outer surface, the diffuse light generator being at least partially transparent to the light beam. The diffuse light generator transmits at least part of the light beam and emits visible diffuse light through the outer surface, and the correlated color temperature (CCT) of the transmitted light is lower than the CCT of the visible diffuse light. The lighting system includes a dark structure that is optically coupled to the environment via the diffuse light generator and provides a substantially uniform background to the first light source.

[0003] US2014 / 133125A1 discloses an illumination system for illuminating an environment with illumination simulating natural illumination. The system comprises: a first light source emitting a visible light beam; a diffuse light generator defined by an inner surface receiving the light beam and an outer surface. The diffuse light generator is at least partially transparent to the light beam. The diffuse light generator transmits at least a portion of the light beam and emits visible diffuse light through the outer surface. The correlated color temperature of the transmitted light is lower than the correlated color temperature of the visible diffuse light. The illumination system comprises a dark box accommodating the first light source, and the dark box is optically coupled to the environment via the diffuse light generator. Summary of the invention

[0004] In today's day and age, people may have to spend a lot of time indoors, especially in situations where one may have to work or go to school in a home environment. Therefore, being close to or exposed to natural daylight in such an environment is very beneficial. Natural daylight has a positive impact on personal health, especially in the production of Vitamin D. Furthermore, natural light may become increasingly important in the future, where the current trend seems to be to promote indoor working. One solution may be to use artificial skylights, which can provide the illusion of sunlight. However, such existing artificial skylights may not resemble the real sky, as objects such as clouds may be missing.

[0005] Therefore, one aspect of the present invention is to provide an alternative light generating system for providing artificial daylight, which preferably further at least partially obviates one or more of the above disadvantages.An object of the present invention may be to overcome or ameliorate at least one disadvantage of the prior art, or to provide a useful alternative.

[0006] According to a first aspect, the present invention provides a light generating system, comprising a housing unit, a first light generating device and one or more objects. In an embodiment, the first light generating device may be configured to generate a first device light. The first device light may particularly include visible light. In a specific embodiment, the visible light may include at least blue light. In an embodiment, the housing unit may include a housing wall and a housing window that encloses the housing space. In an embodiment, the housing wall may be configured to absorb at least a portion of the first device light that reaches the housing wall. In a specific embodiment, the housing window may be translucent for the first device light. Additionally or alternatively, the housing window may scatter at least a portion of the blue light. In an embodiment, the first light generating device and the housing unit may be configured so that the first device light may be provided in the housing space. Additionally or alternatively, a portion of the first device light may escape from the housing space via the housing window. In an embodiment, one or more objects may be configured in the housing space. In particular, one or more objects may be configured to reflect at least a portion of the first device light that reaches one or more objects. In an embodiment, the housing unit, the first light generating device and the one or more objects may be configured so that at least a portion of the first device light that reaches one or more objects reaches the one or more objects only via reflection at the housing window. Therefore, in a specific embodiment, the present invention provides a light generating system, which includes a housing unit, a first light generating device and one or more objects, wherein: the first light generating device is configured to generate a first device light including visible light, wherein the visible light includes at least blue light; the housing unit includes a housing wall and a housing window that encloses a housing space; wherein the housing wall is configured to absorb at least a portion of the first device light reaching the housing wall; and wherein the housing window is translucent to the first device light and scatters at least a portion of the blue light; the first light generating device and the housing unit are configured so that (i) the first device light is provided in the housing space, and (ii) a portion of the first device light escapes from the housing space via the housing window; the one or more objects are configured in the housing space and are configured to reflect at least a portion of the first device light reaching the one or more objects; the housing unit, the first light generating device and the one or more objects are configured so that at least a portion of the first device light reaching the one or more objects reaches the one or more objects only via reflection at the housing window.

[0007] Using the system, a connection with the outside world can be created - among other things - by more realistically imitating natural daylight from (simulated) artificial skylights, as the artificial skylights can include objects such as cloud-like objects (also further indicated herein as "clouds"). In addition, the illusion of different kinds of weather conditions can be provided. The present invention can be used in spaces where access to daylight is limited or absent, such as office spaces, reception areas, and in particular in spaces where access to natural light is not possible, such as underground spaces and control rooms. The present invention can be used to help people maintain a connection with the dynamic natural world outside, thereby making indoor environments with little or no daylight entering more attractive by creating a realistic illusion of skylights (or "roof lights") or windows.

[0008] As described above, the present invention provides a light generating system. Here, the term "light generating system" may particularly refer to a single integrated system, or to a plurality of (modular) housing units that together form a single system. Modular housing units are discussed further below. Therefore, a plurality of (modular) housing units will be applied, and in particular these can be configured adjacently, such as at a distance equal to or less than 10 cm. In this way, a plurality of (modular) housing units can form a single system. A plurality of (modular) housing units can be physically connected to each other. In a specific embodiment, the present invention provides a single integrated system comprising a shared housing and / or a shared exit window. Therefore, the system can be regarded as a single system, which allows the system to provide a window-like experience. The light generating system of the present invention may particularly be an artificial skylight or an artificial window. Therefore, the light generating system can provide the illusion of daylight in an indoor space.

[0009] The light generating system may comprise a first light generating device. The first light generating device may be particularly configured to generate a first device light. The first device light may particularly comprise visible light. In a specific embodiment, the visible light may comprise white light. In a specific embodiment, the visible light may comprise at least blue light. In an embodiment, the first device light may further comprise light having other wavelengths. The first device light is particularly used to simulate daylight, in particular daylight from an artificial window in a wall, a sloping wall, a room divider, a roof, a sloping roof or a ceiling, and even more particularly daylight from an artificial window in a ceiling.

[0010] The light generating system may further include a housing unit. The housing unit may include any shape, such as a cuboid, a parallelepiped, a prism or a cylinder in an embodiment. However, in an alternative embodiment, the housing unit may include an irregular shape. In an embodiment, the housing unit may have a length and a width independently selected from the range of 20-200 cm (such as 40-100 cm). In an embodiment, the housing unit may have a height selected from the range of 4-50 cm (such as 5-30 cm). In an embodiment, the housing unit may enclose the housing space. See also further below for embodiments regarding the housing volume.

[0011] The housing unit may in particular comprise a housing wall and a housing window.In an embodiment, the housing space may be substantially defined by the housing wall and the housing window.

[0012] In an embodiment, the housing wall may be configured to absorb at least a portion of the first device light that reaches the housing wall.

[0013] In particular, the light absorbing material has an absorbance in the range of 50-100%, in particular in the range of 70-100%, for light having a wavelength selected from the visible wavelength range. This may apply to a wavelength range of at least 100 nm, in particular to a wavelength range of at least 250 nm, such as a wavelength range of at least 300 nm (in the range of 380-780 nm). Thus, in a specific embodiment, the housing wall may absorb at least 50%, such as at least 70%, such as at least 85%, of the first device light (or second device light; see also below) that arrives perpendicularly to the housing wall. In a more specific embodiment, the housing wall may absorb at least 90%, such as at least 95%, such as at least 97% of the first (or second) device light that arrives perpendicularly to the housing wall.

[0014] In an embodiment, the absorbance of the housing wall may be substantially uniform. In particular, relative to the average absorbance of the housing wall, at least 5 cm of the housing wall may have a substantially uniform absorbance. 2 The change in the absorptivity of the area may be less than 20%, such as less than 15%, such as less than 10%. In an embodiment, the shell wall may include a first shell wall portion and a second shell wall portion. In particular, the first shell wall portion and the second shell wall portion may be arranged at an angle of 90° in one embodiment, but may be configured at an angle not equal to 90° (such as an angle selected from the range of 45-95°) in other embodiments. In other embodiments, the change in the absorptivity of the first shell wall portion may differ from the absorptivity of the second shell wall portion by less than 20%, such as less than 15%, such as less than 10%.

[0015] In an embodiment, the housing wall may reflect less than 50%, such as less than 30%, such as less than 20% of the first device light (or second device light; see also below) that arrives perpendicularly to the housing wall. In a more specific embodiment, the housing wall may reflect less than 10%, such as less than 5%, such as less than 3% of the first (or second) device light that arrives perpendicularly to the housing wall.

[0016] Additionally or alternatively, the reflectivity of the housing wall may be substantially uniform. In particular, the reflectivity of the housing wall may vary by less than 20%, such as less than 15%, such as less than 10% relative to an average reflectivity of the housing wall (assuming vertical illumination).

[0017] Additionally or alternatively, the surface roughness of the housing wall may be substantially uniform. The surface roughness may be defined by a root mean square (RMS) roughness parameter. The root mean square roughness may be obtained by squaring each height value in the data set and then taking the square root of the average. In particular, the variation in the surface roughness of the housing wall relative to the average RMS of the housing wall may be less than 20%, such as less than 15%, such as less than 10%. In further embodiments, the RMS variation of the first housing wall may differ from the RMS of the second housing wall by less than 20%, such as less than 15%, such as less than 10%.

[0018] In a particular embodiment, the housing wall may be black. The housing wall may be particularly rough, for example comprising matte black corner cubes, a layered structure, or comprising a matte black metal plate comprising a surface pattern (such as a fine mesh of a honeycomb). Such a surface pattern may be embossed or recessed in the metal surface. Alternatively, the housing wall may comprise other black materials, such as fabric, plastic or carbon. In an embodiment, the housing wall may comprise a black coating. In a particular embodiment, the housing wall may comprise carbon nanotubes, in particular carbon nanotubes comprising a coating. Such a material may absorb (far) more than 99% of incident visible light.

[0019] In an embodiment, the housing window may be translucent to the first device light. In particular, in an embodiment, the housing window may scatter at least a portion of the first device light, in particular, the housing window may scatter at least a portion of the blue light. In a specific embodiment, the housing window may scatter all wavelengths in the visible light wavelength range.

[0020] In a specific embodiment, the housing wall and the housing window can enclose the housing space. Therefore, in an embodiment, the housing wall can be used as a light absorbing optical cavity, and the housing window can be used as a light exit window. Further embodiments of the housing window will be discussed below.

[0021] As described above, the first light generating device and the housing unit may be configured such that the first device light is provided in the housing space. The housing space may have a width selected from 1 dm3 -2000dm 3 , such as 5dm 3 -1000dm 3 , such as 10dm 3 -500dm 3 The shell space volume of the range.

[0022] In particular, a portion of the first device light may escape from the housing space via the housing window. In this way, the first device light may be absorbed by the housing wall or may leave the housing space (and thus the housing unit) via the housing window. Thus, in an embodiment, the first device light observable by an observer (outside the housing unit) may in particular be scattered first device light.

[0023] The light generating system may further include one or more objects. In an embodiment, one or more objects may be configured in the housing space and may be configured to reflect at least a portion of the first device light reaching the one or more objects. In this way, in an embodiment, (a portion of) the first device light may be absorbed and / or reflected by one or more objects. In particular, the first device light reflected by one or more objects may then be absorbed by the housing wall, or may leave the housing space (and therefore the housing unit) via the housing window. One or more objects may provide a more realistic skylight and / or the possibility of simulating different weather conditions. One or more objects may simulate one or more of clouds, airplanes, plants and animals, or any other objects. In an embodiment, one or more objects may include two-dimensional (2D) elements. Additionally or alternatively, one or more objects may include three-dimensional (3D) elements.

[0024] As described above, in a specific embodiment, the housing unit, the first light generating device, and the one or more objects can be configured so that at least a portion of the first device light that reaches the one or more objects reaches the one or more objects only via reflection at the housing window. This indirect illumination of the one or more objects will be discussed further below. In an alternative embodiment, at least a portion of the first device light that reaches a portion of the one or more objects can include direct illumination. This direct illumination can result in an optical effect, such as providing a layer of silver edge to the object.

[0025] Here, the phrases "a wavelength in the visible wavelength range", "the wavelength" or "one or more wavelengths" and similar phrases may particularly indicate one wavelength or multiple wavelengths. Thus, the term "wavelength" or "the wavelength" in phrases such as "transparent to a wavelength" or "transmissive to the wavelength" or "reflective to the wavelength" and similar phrases may particularly refer to multiple wavelengths, such as a wavelength in a wavelength range of at least 100 nm, in particular a wavelength in a wavelength range of at least 250 nm, such as a wavelength in a wavelength range of at least 300 nm.

[0026] The phrase "light reaching an object" and similar phrases may be defined in embodiments as a portion of the light that actually reaches an object, and may therefore be reflected, absorbed or transmitted (one or more) by the object. Thus, "first device light reaching one or more objects" may be defined in embodiments as a portion of the first device light that actually reaches an object, and may therefore be reflected, absorbed or transmitted (one or more) by the object. Thus, "first device light reaching a housing wall" may be defined as a portion of the first device light that actually reaches a housing wall, and may be reflected, absorbed or transmitted (one or more) by the housing wall. Thus, substantially the first device light may reach an object, in particular due to reflection via a housing window, transmission or scattering by a housing window, or absorption by a housing wall.

[0027] The transmittance T (or light transmittance) can be determined by providing light with a first intensity I1 at a specific wavelength to a light-transmitting material under vertical irradiation, and correlating the intensity I2 of the light at the wavelength measured after transmission through the material with the first intensity of the light provided to the material at the specific wavelength, so T=I2 / I1. Similarly, the reflectance R can be determined by correlating the intensity I3 of the light at the wavelength measured after reflection by the material with the first intensity I1 of the light provided to the material at the specific wavelength. So R=I3 / I1. In an embodiment, the absorptivity A can be defined as A=1-(T+R) (see also E-208 and E-406 of CRC Handbook of Chemistry and Physics, 69th Edition, 1088-1989).

[0028] In an embodiment, the housing window may include nanoparticles having one or more sizes selected from the range of 20-240nm, more particularly the range of 40-180nm, such as the range of 60-150nm, particularly the range of 90-120nm. In a specific embodiment, the housing window may include a Rayleigh diffuser. In this way, the window can provide Rayleigh scattering from the first device light. In an embodiment, the first device light may include white type light. In particular, all wavelengths may be scattered, but blue light may be scattered more than red light. The process of Rayleigh scattering and its wavelength dependence have been described in WO2014076656A1, which is incorporated herein by reference. Therefore, in a specific embodiment, the housing window includes nanoparticles having one or more sizes selected from the range of 40-180nm, and wherein the first device light includes white type light. Therefore, the housing window can be a Rayleigh scatterer for the first device light, and transmits a portion of the first device light and reflects (in particular at least via scattering) a portion of the first device light.

[0029] In an embodiment, the particle may have a particle size defined by the smallest rectangular prism defining the corresponding particle, wherein such rectangular prism has a length D1, a width D2 and a height D3. In an embodiment, one or more of D1, D2 and D3 may be selected from the range of 20-240 nm, more particularly the range of 40-180 nm, such as the range of 60-150 nm, particularly the range of 90-120 nm.

[0030] In an embodiment, the particles may have an equivalent spherical diameter D selected from the range of 20-240 nm, more particularly the range of 40-180 nm, such as the range of 60-150 nm, particularly the range of 90-120 nm.

[0031] The equivalent spherical diameter (ESD) of an (irregular) shaped object is the diameter of a sphere of equivalent volume. Thus, the equivalent spherical diameter (ESD) of a cube with side length a is In the xyz coordinate system, a sphere of diameter d can be deformed into any other shape (in the xyz plane) without changing volume, and the equivalent spherical diameter of that shape will be d.

[0032] The particle size can be determined by methods known in the art (such as one or more of optical microscopy, SEM and TEM). As known in the art, the size can be number average. In addition, the above aspect ratio can refer to a plurality of particles with different aspect ratios. Therefore, the particles can be substantially the same, but the particles can also be different from each other, such as two or more subsets of particles, wherein the particles are substantially the same within the subset. The particles can have a unimodal particle size distribution or a multimodal particle size distribution.

[0033] Therefore, the particles may be different from each other. For example, the particles may have a size distribution of one or more of a particle length, a particle height, and an intermediate length. Therefore, in an embodiment, on average, the particles will have a size as described herein. For example, at least 50% by weight of the particles may conform to the size (including ratios) indicated herein, such as at least 75% by weight, such as at least 85% by weight. In an alternative embodiment, at least 50% of the total number of particles may conform to the size (including ratios) indicated herein, such as at least 75%, such as at least 85%.

[0034] As described above, in an embodiment, at least a portion of the first device light reaching one or more objects may reach the one or more objects only via reflection at the housing window. In order to reduce the amount of direct irradiation of one or more objects, the housing unit further includes a first blocking element, which is configured between the first light generating device and the one or more objects and is configured to prevent direct irradiation of the one or more objects with at least a portion of the first device light. The first blocking element can increase the possibility of arranging the first light generating device in the housing space while still preventing direct irradiation of one or more objects by the first light generating device. The blocking element may, for example, include a matte black corner cube, a layered structure, or include a matte black metal plate including a surface pattern (such as a fine mesh of a honeycomb). Such a surface pattern may be embossed or recessed in the metal surface. Alternatively, the blocking element may include other black materials, such as fabric, plastic, or carbon.

[0035] In particular, the first blocking element can absorb at least 50%, such as at least 70%, such as at least 85%, of the first (or second) device light that reaches the first blocking element vertically. In a more specific embodiment, the first blocking element can absorb at least 90%, such as at least 95%, such as at least 97% of the first (or second) device light that reaches the first blocking element vertically. The embodiments described for the housing wall can also be applied to the first blocking element. The materials and coatings described above can also be applied to the blocking element.

[0036] Therefore, the housing unit further comprises a first blocking element, which is arranged between the first light generating device and the one or more objects and is configured to prevent direct illumination of the one or more objects with at least a portion of the first device light.

[0037] In particular, the first light generating device and the first blocking element can be configured in an embodiment so that less than 10%, such as less than 5%, such as less than 2% of the total spectral power in the visible light wavelength range of the first device light reaching one or more objects is direct light. Additionally or alternatively, in an embodiment, at least 90%, such as at least 95%, such as at least 98% of the total spectral power in the visible light wavelength range of the first device light reaching one or more objects can be indirect light. In this way, the object can have a desired brightness level. In particular, the sum of the first device light that reaches one or more objects indirectly and the first device light that reaches one or more objects directly can be 100%. Therefore, in a specific embodiment, the first light generating device and the first blocking element are configured so that less than 5% of the total spectral power of the first device light that reaches one or more objects is direct light, and at least 95% of the total spectral power of the first device light that reaches one or more objects is indirect light.

[0038] In an embodiment, the first device light may have a first optical axis (O1). In particular, the first optical axis (O1) and the housing window have a common first angle (α1). In an embodiment, the first light generating device may be configured such that the first angle (α1) may be selected from a range of 5-85°, such as 10-80°, such as 15-75°. In this way, the relative amounts of reflection and scattering of the first device light may provide improved daylight imitation. Therefore, in a specific embodiment, the first device light has a first optical axis (O1), wherein the first optical axis (O1) and the housing window have a common first angle (α1), wherein the first angle (α1) is selected from a range of 10-80°.

[0039] In a further embodiment, the first light generating device and the housing window may be configured so that at least 10%, such as at least 20%, such as at least 30%, of the spectral power within the visible wavelength range of the first device light reaching the housing window can be transmitted through the housing window. In this way, the light generating device can provide sufficient spectral power to the observer. Additionally or alternatively, the first light generating device and the housing window may be configured so that at least 10%, such as at least 20%, such as at least 30% of the spectral power within the visible wavelength range of the first device light reaching the housing window can be reflected by the housing window. In a further embodiment, the first light generating device and the housing window may be configured so that less than 15%, such as less than 10%, such as less than 5%, of the spectral power within the visible wavelength range of the first device light reaching the housing window can be absorbed by the housing window. In this way, there may be sufficient spectral power to provide indirect illumination of one or more objects configured in the housing space. In particular, the sum of the first device light reaching the housing window reflected by the housing window and the first device light reaching the housing window transmitted by the housing window can be a maximum of 100% (and can be in particular at least about 95%). Therefore, in a specific embodiment, the first light generating device and the housing window are configured such that (i) at least 20% of the spectral power of the first device light reaching the housing window is transmitted through the housing window, and (ii) at least 20% of the spectral power of the first device light reaching the housing window is reflected by the housing window.

[0040] In an embodiment, at least one object may be irregularly shaped. In this way, the object may better mimic natural objects such as clouds or plants, because such natural objects may also be irregularly shaped. Additionally or alternatively, in an embodiment, three or more objects may not be arranged in a regular pattern. For example, in one embodiment, three objects may be arranged in the shape of an isosceles triangle. In an alternative embodiment, three or more objects may be arranged in a row at non-equidistant intervals. However, other arrangements are also possible. Therefore, in a specific embodiment, one or more objects apply one or more of the following: (i) at least one object is irregularly shaped, and (ii) three or more objects are not arranged in a regular pattern. In a more specific embodiment, at least one object may have the shape of a cloud. In such an embodiment, alternating between three or more objects may provide a changing view or scene in the system. Such a shape and / or pattern may improve the illusion of an actual skylight or window.

[0041] In an embodiment, the one or more objects may comprise a combined object volume of 1-25%, such as 2-20%, such as 4-15% of the volume of the housing space.

[0042] In further embodiments, at least one object may include a ball of plush (such as cotton wool), glass wool, metal wool, plastic wool, shredded paper, shredded fabric, shredded metal foil or fiber pad. Additionally or alternatively, at least one object may include (porous) foam, plastic foil, plastic sheet, or paper. Thus, in a specific embodiment, at least one object includes a ball of plush. In an embodiment, at least one object may be white. Additionally or alternatively, at least one object may be gray. In an embodiment, at least one object may be transmissive. Additionally or alternatively, at least one object may be translucent. In an embodiment in which the light generating system includes a plurality of objects, at least one object may have a spectral property different from at least one other object. In an alternative embodiment, one or more objects may include the same spectral property. In a specific embodiment, all objects may be white. In an alternative embodiment, all objects may be gray. Additionally or alternatively, all objects may be transmissive. In a specific embodiment, all objects may be translucent.

[0043] In an embodiment, the first light generating device may have a controllable spectral power distribution of the first device light. In particular, the controllable spectral power distribution of the first device light may include one or more different spectral power distributions of white type light. Therefore, in a specific embodiment, the first light generating device has a controllable spectral power distribution of the first device light, including one or more different spectral power distributions of white type light. In an embodiment, the first light generating device may include a single first light source, such as a single LED. In an alternative embodiment, the first light generating device may include a first array of first light sources. In particular, one or more first light sources may be individually controllable. In this way, changing weather patterns, such as the sun and clouds, can be emulated by illuminating changing parts of one or more objects.

[0044] The term "white light" and similar terms are known to the person skilled in the art in this document. It may particularly relate to light having a correlated color temperature (CCT) between about 1800K and 20000K, such as between 2000 and 20000K, in particular 2700-20000K, for general lighting, in particular in the range of about 2000-7000K, such as in the range of 2700K and 6500K. In an embodiment, for example for the purpose of backlighting, or for other purposes, the correlated color temperature (CCT) may in particular be in the range of about 7000K and 20000K. Still further, in an embodiment, the correlated color temperature (CCT) is in particular within about 15SDCM (standard deviation of color matching) from the BBL (black body locus), in particular within about 10SDCM from the BBL, even more in particular within about 5SDCM from the BBL. In a specific embodiment, the correlated color temperature (CCT) may be selected from the range of 6000-12000 K, such as from the range of 7000-12000 K, such as at least 8000 K. Still further, in an embodiment, the correlated color temperature (CCT) may be selected from the range of 6000-12000 K, such as from the range of 7000-12000 K, in combination with a CRI of at least 70.

[0045] In a specific embodiment, when the correlated color temperatures (CCTs) of the first type of first device light and the second type of first device light differ by at least 500K, such as at least 750K, as in an embodiment at least 1000K, the respective CCTs of the first type of light and the second type of light may be different.

[0046] In order to control the spectral power distribution of the first device light, the light generating system may further comprise a control system. In an embodiment, the control system may be configured to control the first light generating device in particular depending on one or more of an input signal of a user interface, a sensor signal (of a sensor) and a timer. Therefore, in a specific embodiment, the light generating system further comprises a control system, wherein the control system is configured to control the first light generating device in dependence on one or more of an input signal of a user interface, a sensor signal and a timer. In this way, the spectral power distribution of the first device light may be adjusted to better mimic current local weather conditions and / or the circadian appearance of daylight.

[0047] In an embodiment, the light generating system may further include a second light generating device. In particular, the second light generating device may be configured to generate a second device light including visible light. In an embodiment, the second device light may include white light. The embodiments of "white light", CCT and CRI described above for the first device light may also be applied to the second device light. In other embodiments, the second device light may include colored light. In an embodiment, the second light generating device may have a controllable spectral power distribution of the second device light, including one or more spectral power distributions of white light and / or one or more spectral power distributions of colored light.

[0048] In an embodiment, the second light generating device and the housing unit may be configured so that the second device light may be provided in the housing space. Additionally or alternatively, the second light generating device and the housing unit may be configured so that a portion of the second device light may escape from the housing space via the housing window. In an embodiment, the housing unit, the second light generating device, and the one or more objects may be configured so that at least a portion of the second device light reaching the one or more objects only directly reaches the one or more objects. Therefore, in a specific embodiment, the light generating system further comprises a second light generating device, wherein the second light generating device is configured to generate a second device light comprising visible light; the second light generating device and the housing unit are configured so that (i) the second device light is provided in the housing space, and (ii) a portion of the second device light escapes from the housing space via the housing window; and the housing unit, the second light generating device, and the one or more objects are configured so that at least a portion of the second device light reaching the one or more objects only directly reaches the one or more objects. The second light may be particularly useful for providing the illusion of different kinds of weather and circadian appearances by directly illuminating one or more objects. In further embodiments, the second light generating device may comprise a plurality of different light generating devices.

[0049] In an embodiment, during operation, the spectral power distribution of the first device light and the second device light may be different (see also further below).

[0050] More specifically, the second light generating device and one or more objects may be configured in an embodiment so that at least 50%, such as at least 60%, such as 70%, of the total spectral power in the visible light wavelength range of the second device light reaching one or more objects is direct light. Additionally or alternatively, the second light generating device and one or more objects may be configured in an embodiment so that less than 50%, such as less than 40%, such as less than 30%, of the total spectral power in the visible light wavelength range of the second device light reaching one or more objects is indirect light. The percentage mentioned here may specifically refer to the spectral power of the second device light that actually reaches one or more objects. Therefore, the spectral power of the second device light that does not reach one or more objects may not be considered here. In addition, since the housing wall can highly absorb the second device light, not the entire surface area of ​​one or more objects can receive the spectral power of the second device light. Therefore, in a specific embodiment, the second light generating device and one or more objects are configured so that at least 60% of the total spectral power of the second device light reaching one or more objects is direct light, and less than 40% of the total spectral power of the second device light reaching one or more objects is indirect light.

[0051] In a further embodiment, the second light generating device and the housing window may be configured such that at least 15%, such as at least 20%, such as at least 30%, of the spectral power in the visible light wavelength range of the second device light reaching the housing window may be transmitted through the housing window. Additionally or alternatively, the second light generating device and the housing window may be configured such that at least 15%, such as at least 20%, such as at least 30% of the spectral power in the visible light wavelength range of the second device light reaching the housing window is reflected by the housing window. Therefore, in a specific embodiment, the second light generating device and the housing window are configured such that (i) at least 20% of the spectral power of the second device light reaching the housing window is transmitted through the housing window, and (ii) at least 20% of the spectral power of the second device light reaching the housing window is reflected by the housing window.

[0052] As described above, in an embodiment, the light generating system may further include a control system. In particular, the control system may be configured to control one or more of the first light generating device and the second light generating device depending on one or more of an input signal of a user interface, a sensor signal (of a sensor), and a timer. In this way, light generation can better mimic different weather conditions. Therefore, in a specific embodiment, the light generating system further includes a control system, wherein the control system is configured to control the first light generating device and the second light generating device depending on one or more of an input signal of a user interface, a sensor signal, and a timer.

[0053] In an embodiment, the second light generating device may be configured to generate a white second device light. In other embodiments, the second light generating device may be configured to generate a colored second device light. In particular, the first light generating device and the second light generating device each have an operable mode in which the spectral power distribution of the first device light and the spectral power distribution of the second device light are different. For example, they may differ in one or more of a color point and a correlated color temperature.

[0054] In particular, in embodiments, one or more of a user interface, a sensor signal, and a timer may provide an input signal to a control system in embodiments to configure the color of the second device light. The user interface may enable manual changing of the color of the second device light to a circadian appearance. Additionally or alternatively, the sensor signal or the timer may automatically adapt the color of the second device light to a circadian appearance. Furthermore, the user interface and / or the sensor signal may be used to adapt the color of the second device light to current weather conditions.

[0055] In a specific embodiment, the color or color point of the first type of light and the second type of light may be different when the corresponding color points of the first type of light and the second type of light differ by at least 0.01 for u' and / or by at least 0.01 for v', even more particularly by at least 0.02 for u' and / or by at least 0.02 for v'. In a more specific embodiment, the corresponding color points of the first type of light and the second type of light may differ by at least 0.03 for u' and / or by at least 0.03 for v'. Here, u' and v' are the color coordinates of the light in the CIE 1976 UCS (Uniform Chromaticity Scale) diagram.

[0056] Spectral power distributions of different light sources with centroid wavelengths that differ by at least 10 nm, such as at least 20 nm, or even at least 30 nm can be considered to be different spectral power distributions, such as different colors. Typically, the difference in centroid wavelength is no greater than about 400 nm, such as no greater than 350 nm.

[0057] In a particular embodiment, the correlated color temperature (CCT) of the first device light and the second device light may differ by at least 500K, such as at least 750K, such as at least 1000K in an embodiment.

[0058] In an operational mode of the system, the first device light is white light and the second device light is white light. In (other) embodiments, the first device light is white light and the second device light is white light, wherein the first device light and the second device light have different correlated color temperatures. In other operational modes of the system, the first device light is white light and the second device light is colored light. In still other operational modes of the system, the first device light is white light and the second device light is light with a spectral power distribution that varies over time. In specific embodiments, in other operational modes of the system, the first device light is white light and the second device light includes one or more of the colors of a dawn and sunset sky. In specific embodiments, the second device light may be white light to simulate a bright sunny day. In other embodiments, the second device light may be pink to simulate pinkish clouds at night.

[0059] Colored light can be, for example, violet, indigo, blue, cyan, green, yellow, orange, or red. The terms "violet light" or "violet emission" and similar terms may particularly relate to light having a wavelength in the range of about 380-440 nm. In a specific embodiment, violet light may have a centroid wavelength in the range of 380-440 nm. The terms "blue light" or "blue emission" and similar terms may particularly relate to light having a wavelength in the range of about 440-490 nm (including some violet and cyan hues). In a specific embodiment, blue light may have a centroid wavelength in the range of 440-490 nm. The terms "green light" or "green emission" and similar terms may particularly relate to light having a wavelength in the range of about 490-560 nm. In a specific embodiment, green light may have a centroid wavelength in the range of 490-560 nm. The terms "yellow light" or "yellow emission" and similar terms may particularly relate to light having a wavelength in the range of about 560-590 nm. In a specific embodiment, yellow light may have a centroid wavelength in the range of 560-590 nm. The terms "orange light" or "orange emission" and similar terms may particularly relate to light having a wavelength in the range of about 590-620 nm. In a specific embodiment, orange light may have a centroid wavelength in the range of 590-620 nm. The terms "red light" or "red emission" and similar terms may particularly relate to light having a wavelength in the range of about 620-750 nm. In a specific embodiment, red light may have a centroid wavelength in the range of 620-750 nm. The terms "cyan light" or "cyan emission" and similar terms may particularly relate to light having a wavelength in the range of about 490-520 nm. In a specific embodiment, cyan light may have a centroid wavelength in the range of 490-520 nm. The terms "amber light" or "amber emission" and similar terms may particularly relate to light having a wavelength in the range of about 585-605 nm, for example about 590-600 nm. In a specific embodiment, amber light may have a centroid wavelength in the range of 585-605 nm. The phrase "light having one or more wavelengths in a wavelength range" and similar phrases may specifically indicate that the indicated light (or radiation) has a spectral power distribution having at least one or more intensities at these one or more wavelengths in the indicated wavelength range. For example, a solid-state light source emitting blue will have a spectral power distribution having intensities at one or more wavelengths in the wavelength range of 440-495 nm.

[0060] In an embodiment, the light generating system may further comprise a first grid. The first grid may in particular be arranged downstream of the housing window. Thus, the first grid may be arranged outside the housing. In an alternative (or additional) embodiment, the first grid may be arranged directly upstream of the housing window.

[0061] The first grid may in particular comprise a first grid structure and a first grid opening. The first grid opening may in particular be defined by the first grid structure. In an embodiment, the first grid structure may be configured to block a portion of the first device light, and the first grid opening may be configured to allow the first device light to propagate through. In an embodiment, blocking a portion of the first device light may comprise absorbing or reflecting a portion of the first device light. In particular, blocking a portion of the first device light may be interpreted as hiding a portion of the housing window from an observer. The portion of the housing window that may be hidden may in particular depend on the position of the observer. In this way, the artificial sky seen by the observer may change in case the observer is moving, since different viewing angles may result in different portions of the housing window being blocked.

[0062] Therefore, in a specific embodiment, the light generating system further includes a first grid configured downstream of the housing window or directly upstream of the housing window, wherein the first grid includes a first grid structure and a first grid opening, wherein the first grid structure is configured to block a portion of the first device light, and wherein the first grid opening is configured to allow the first device light to propagate through.

[0063] The first grid structure may include a plurality of first grid structure elements. In an embodiment, the first grid structure may include a regular pattern, such as an array of first grid openings of regular shapes separated by first grid structure elements. In an alternative embodiment, the first grid may include an irregular pattern, such as an array of grid openings of irregular shapes separated by first grid structure elements. In an embodiment, the first grid structure may be one or more of reflective, transmissive or opaque to the first (or second) device light. Additionally or alternatively, the first grid structure may be white. In other embodiments, the first grid structure may have other colors. In an embodiment, the first grid structure may include any shape.

[0064] In an embodiment including a second device, the first grid structure may also be configured to block a portion of the second device light, and the first grid openings may be configured to also allow the second device light to propagate through. In particular, such a first grid may provide a sense of perspective to the user.

[0065] In an embodiment, the first grid structure may have a length corresponding to the length or width of the housing unit. Therefore, in a specific embodiment, the length of the first grid structure may be selected from the range of 20-200cm, such as 40-100cm. In an alternative embodiment, the first grid structure may be smaller than the housing unit, in which case the first grid structure may have a length selected from the range of 3-100cm, such as 5-50cm. In an embodiment, the first grid structure may have a height selected from the range of 2-20cm, such as 3-10cm. In an embodiment, the first grid structure element may have a width (or thickness) selected from the range of 0.1-2cm, such as 0.5-1cm. In a specific embodiment, the first grid structure element may have a constant width (or thickness). In such an embodiment, the first grid structure element may be parallel. In an alternative embodiment, the width (or thickness) of the first grid structure element may be different at different positions. In such an embodiment, the first grid structure element may be tapered.

[0066] In an embodiment, the light generating system may further include a diffuser. The diffuser may be particularly configured downstream of the housing window. Alternatively, the diffuser may be configured directly upstream of the housing window. In an embodiment, the diffuser may be configured to diffusely transmit at least a portion of the first device light and the optional second device light reaching the diffuser. Therefore, in a specific embodiment, the light generating system further includes a diffuser configured downstream of the housing window or directly upstream of the housing window, the diffuser being configured to diffusely transmit at least a portion of the first device light reaching the diffuser. The diffuser may particularly provide more uniform external lighting. Both the first grid and the diffuser will be usable, in particular the first grid may be configured downstream of the diffuser.

[0067] In an embodiment, at least one of the one or more objects may be configured to be movable in the housing. Therefore, in a specific embodiment, the light generating system may further include a first actuator in an embodiment. In particular, the first actuator may be configured to move at least one of the one or more objects within the housing (i.e., one or more movable objects). In an embodiment, the one or more objects may be configured on a carrier (such as an infinite loop or a rotating wheel). In such an embodiment, the first actuator may be configured to move the carrier and thus move the one or more objects. However, other embodiments may also be possible.

[0068] In a further embodiment, the control system may be configured to control the first actuator depending on one or more of an input signal of a user interface, a sensor signal (of a sensor) and a timer. Therefore, in a specific embodiment, the light generating system further comprises a first actuator, wherein at least one of the one or more objects is configured to be movable in the housing; and the first actuator is configured to move at least one of the one or more objects within the housing. In this way, at least one of the one or more objects can be displaced. In an embodiment, the object can be moved within the housing space. In this way, the light generating system can dynamically imitate the sky. In a further embodiment, at least one of the one or more objects can be displaced in a manner that may obstruct the object. The object can, for example, be moved behind a shield or into a cavity within the housing space. In this way, the light generating system can show one or more objects at a time and show fewer objects at another time. By using such a first actuator, the skylight can be continuously adaptable.

[0069] In an embodiment, the light generating system may further comprise a second grid.In an embodiment, the second grid may be statically configured in the housing.

[0070] During operation of the light generating system, the second grid may be configured upstream of the housing window and downstream of one or more objects at least part of the time. The second grid may particularly include a second grid structure and a second grid opening defined by the second grid structure. In an embodiment, the second grid structure may be configured to block a portion of the first device light reflected at the one or more objects, and wherein the second grid opening is configured to allow a portion of the first device light reflected at the one or more objects to propagate through. The second grid structure may include second grid structure elements. The additional embodiments described for the first grid may also apply to the second grid.

[0071] In an alternative embodiment, the second grid may be particularly configured to be movable in the housing. In such an embodiment, the light generating system may further include a second actuator. The second actuator may be particularly configured to move the second grid within the housing. By using this second actuator, the skylight may be continuously adaptable. In a further embodiment, the light generating system may include a control system, wherein the control system may be configured to control the second actuator. In particular, the second actuator may control the (movable) second grid depending on one or more of an input signal of a user interface, a sensor signal (of a sensor) and a timer. In particular, one or more of a user interface, a sensor signal and a timer may provide an input signal to the control system in an embodiment to configure the configuration of the second grid. The user interface may enable the configuration of the second grid to be manually changed to weather conditions. Additionally or alternatively, a sensor signal or a timer may automatically adapt the configuration of the second grid to weather conditions. In addition, the user interface and / or the sensor signal may be used to adapt the configuration of the second grid to weather conditions. In particular, depending on the configuration of the second grid, the object may be hidden within the housing unit (hidden from an observer) or may be exposed within the housing unit (visible to an observer). Therefore, in a specific embodiment, the light generating system further includes a second grid and a second actuator, wherein: the second grid is configured to be movable in the housing; during operation, the second grid is configured upstream of the housing window and downstream of one or more objects at least part of the time; the second grid includes a second grid structure and a second grid opening, wherein the second grid structure is configured to block a portion of the first device light reflected at the one or more objects, and wherein the second grid opening is configured to allow a portion of the first device light reflected at the one or more objects to propagate through; and the second actuator is configured to move the second grid within the housing.

[0072] In an embodiment, the second grid may be arranged on a carrier, such as an endless loop or a rotating wheel. In this way, the second actuator may be arranged to move the carrier, and thus the second grid. However, other embodiments may also be possible.

[0073] In this way, a continuously adaptable light generating system may be provided, as the observer may see different objects (different parts of the object) through the second grid.

[0074] In particular, the use of a user interface, a sensor signal or a timer may help to adjust the appearance of the light generating system relative to an external stimulus. In an embodiment, the light generating system may include a plurality of second grids, wherein the second grids may differ in one or more of the movement speed and the movement direction. In an embodiment, the second grids may be replaceable or changeable. This may allow (manually) changing the visible pattern of one or more objects.

[0075] As described above, the housing unit may be a modular housing unit. In such an embodiment, the light generating system may include a plurality of modular housing units. In an embodiment, the light generating system may include one or more housing walls between two modular housing units. Additionally or alternatively, in an embodiment, there may be no housing wall between two modular housing units. In particular, the light generating system including a plurality of modular housing units may include a main control unit in an embodiment. In an embodiment, such a main control unit may be configured to control a plurality of modular housing units and the light generating devices therein.

[0076] The light generating system may be part of or may be applied in, for example, an office lighting system, a home application system, a store lighting system, a family lighting system, an accent lighting system, a spotlight lighting system, a theater lighting system, a fiber optic application system, a projection system, a self-luminous display system, a pixelated display system, a segmented display system, a warning sign system, a medical lighting application system, an indicator sign system, a decorative lighting system, a portable system, an automotive application, a (outdoor) road lighting system, a city lighting system, a greenhouse lighting system, horticultural lighting, digital projection, or an LCD backlight. The light generating system (or illuminator) may be part of or may be applied in, for example, an optical communication system or a disinfection system.

[0077] In a further aspect, the present invention may provide a space. In an embodiment, the space may include one or more of a wall, a sloping wall, a room divider, a roof, a sloping roof, and a ceiling. In particular, the space may further include a light generating system suspended from the roof, the sloping roof, or the ceiling. In this way, the light generating system may act as a skylight illusion. Additionally or alternatively, the space may include a light generating system attached to a wall, a sloping wall, or a room divider. In this way, the light generating system may act as a window illusion. Therefore, in one aspect, the present invention provides a space including a ceiling, wherein the space further includes a light generating system suspended from the ceiling.

[0078] The term "space" may, for example, relate to (a part of) a reception area, such as a restaurant, a hotel, a clinic or a hospital, etc. The term "space" may also relate to (a part of) an office, a department store, a warehouse, a cinema, a church, a theater, a library, etc. However, the term "space" may also relate to (a part of) a workspace in a vehicle, such as a cab of a truck, a cab of an airplane, a cab of a ship (ship), a cab of a car, a cab of a crane, a cab of an engineering vehicle (such as a tractor), a cab of a train carriage, etc. The term "space" may also relate to (a part of) a workspace, such as an office, a (production) factory, a power plant (such as a nuclear power plant, a gas power plant, a coal power plant, etc.), etc. For example, the term "space" may also relate to a control room, a security room, etc. In particular, the term "space" may refer to an indoor space herein. In yet other embodiments, the term "space" may also relate to a toilet or a bathroom. In yet other embodiments, the term "space" may also relate to an elevator. In an embodiment, the term "space" may also refer to a conference room, a classroom, an indoor corridor, an indoor aisle, an indoor space in a nursing home, an indoor space in a sanatorium, etc. In an embodiment, the term "space" may refer to an indoor sports space, such as a gymnasium, a gymnastics hall, an indoor ball game space, a ballet studio, a swimming pool, a locker room, etc. In an embodiment, the term "space" may refer to an (indoor) bar, an (indoor) discotheque, etc.

[0079] In yet further embodiments, the invention may provide a lighting system for office lighting, reception area lighting, home lighting, station lighting or interior vehicle lighting. However, other applications may also be possible.

[0080] The terms "upstream" and "downstream" relate to the arrangement of items or features relative to the propagation of light from a light generating device (here in particular a light source), wherein, relative to a first position in a light beam from the light generating device, a second position in the light beam closer to the light generating device is "upstream" and a third position in the light beam further away from the light generating device is "downstream".

[0081] The terms "visible", "visible light" or "visible emission" and similar terms refer to light having one or more wavelengths in the range of about 380-780 nm. In this document, UV may particularly refer to wavelengths selected from the range of 190-380 nm (such as 200-380 nm). The terms "light" and "radiation" are used interchangeably herein, unless it is clear from the context that the term "light" refers only to visible light. The terms "light" and "radiation" may therefore refer to UV radiation, visible light and IR radiation. In specific embodiments, in particular for lighting applications, the terms "light" and "radiation" refer to (at least) visible light.

[0082] The term "control" and similar terms refer in particular at least to determining the operation of a behavior or a supervisory element. Therefore, in this article, "control" and similar terms may, for example, refer to applying behavior (determining the operation of a behavior or a supervisory element) to an element, such as, for example, measuring, displaying, actuating, opening, moving, changing temperature, etc. In addition, the term "control" and similar terms may additionally include monitoring. Therefore, the term "control" and similar terms may include applying behavior to an element, and also applying behavior to an element and monitoring the element. The control of the element may be completed with a control system, which may also be indicated as a "controller". Therefore, the control system and the element may be functionally coupled at least temporarily or permanently. The element may include a control system. In an embodiment, the control system and the element may not be physically coupled. Control may be completed via wired and / or wireless control. The term "control system" may also refer to a plurality of different control systems, which are particularly functionally coupled, and wherein, for example, one control system may be a master control system, and one or more other control systems may be slave control systems. The control system may include or may be functionally coupled to a user interface.

[0083] The control system may also be configured to receive and execute instructions from a remote control. In an embodiment, the control system may be controlled via an App on a device such as a portable device (e.g., a smartphone or I-Phone, a tablet, etc.). Thus, the device is not necessarily coupled to the lighting system, but may be (temporarily) functionally coupled to the lighting system.

[0084] 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 a control in slave mode. For example, the lighting system may be identified with a code, in particular a unique code for the respective lighting system. The control system of the lighting system may be configured to be controlled by an external control system, which accesses the lighting system based on the knowledge of the (unique) code (input via a user interface or input using an optical sensor (e.g. a QR code reader)). The lighting system may also include components for communicating with other systems or devices, such as based on Bluetooth, Thread, WIFI, LiFi, ZigBee, BLE or WiMAX, or other wireless technologies.

[0085] The system or device or equipment may perform actions in a "mode" or "operating mode" or "operable mode". The term "operable mode" may also be indicated as a "control mode". Similarly, in a method, an action or phase or step may be performed in a "mode" or "operating mode" or "operable mode". This does not exclude that the system, or device, or equipment may also be adapted to provide another control mode, or multiple other control modes. Similarly, this may not exclude that one or more other modes may be performed before and / or after the execution of the mode.

[0086] However, in an embodiment, a control system may be available, which is adapted to provide at least a control mode. If other modes are available, the selection of such a mode may in particular be performed via a user interface, although other options (such as performing a mode according to a sensor signal or a (time) scheme) may also be possible. In an embodiment, an operating mode may also refer to a system, or a device, or an apparatus that can only be operated in a single operating mode (i.e. "on", without further tunability).

[0087] Thus, in an embodiment, the control system may be controlled depending on one or more of an input signal of a user interface, a sensor signal (of a sensor), and a timer.The term "timer" may refer to a clock and / or a predetermined time scheme.

[0088] In yet another aspect, the present invention also provides a lamp or illuminator including a light generating system as defined herein. The illuminator may further include a housing, an optical element, a shutter, etc. The lamp or illuminator may further include a housing that encloses the light generating system. The lamp or illuminator may include a light window or housing opening in the housing, through which the system light escapes from the housing. In yet another aspect, the present invention also provides a projection device including a light generating system as defined herein. In particular, a projection device or "projector" or "image projector" may be an optical device that projects an image (or moving image) onto a surface (such as, for example, a projection screen). The projection device may include one or more light generating systems, such as described herein. Therefore, in one aspect, the present invention also provides a light generating device selected from a group of lamps, illuminators, projector devices, disinfection equipment, photochemical reactors, and optical wireless communication devices, including a light generating system as defined herein. The light generating device may include a housing or carrier configured to accommodate or support one or more elements of the light generating system.

[0089] Instead of the term "lighting device" or "lighting system" and similar terms, the term "light generating device" or "light generating system" (and similar terms) may also be applied. A lighting device or a lighting system may be configured to generate device light (or "lighting device light") or system light (or "lighting system light"). As mentioned above, the terms light and radiation may be used interchangeably.

[0090] As described above, the light generating system comprises a first light generating device and an optional second light generating device. In the following, some aspects of the light generating devices are described.

[0091] The light generating device may in particular be configured to generate device light. In particular, the light generating device may comprise a light source. The light source may in particular be configured to generate light source light. In embodiments, the device light may consist essentially of device light. In other embodiments, the device light may consist essentially of converted light source light. In yet other embodiments, the device light may comprise (unconverted) light source light and converted light source light. The light source light may be converted into luminescent material light with a luminescent material and / or into upconverted light with an upconverter (see also below). The term "light generating device" may also refer to a plurality of light generating devices that may provide device light having substantially the same spectral power distribution. In specific embodiments, the term "light generating device" may also refer to a plurality of light generating devices that may provide device light having different spectral power distributions.

[0092] The term "light source" may in principle relate to any light source known in the art. It may be a conventional (tungsten) bulb, a low-pressure mercury lamp, a high-pressure mercury lamp, a fluorescent lamp, an LED (light emitting diode). In a specific embodiment, the light source comprises a solid-state LED light source (such as an LED or a laser diode (or "diode laser")). The term "light source" may also relate to a plurality of light sources, for example 2-2000 (solid-state) LED light sources. Therefore, the term LED may also refer to a plurality of LEDs. In addition, the term "light source" may also refer to a so-called chip-on-board (COB) light source in an embodiment. The term "COB" refers in particular to an LED chip in the form of a semiconductor chip, which is neither packaged nor connected, but is directly mounted on a substrate such as a PCB. Therefore, a plurality of light-emitting semiconductor light sources may be configured on the same substrate. In an embodiment, a COB is a plurality of LED chips configured together into a single lighting module.

[0093] The term "light source" may also refer to a chip scale package (CSP). A CSP may include a single solid-state die on which a layer containing a luminescent material is provided. The term "light source" may also refer to a mid-power package. A mid-power package may include one or more solid-state dies. (One or more) dies may be covered by a layer containing a luminescent material. The die size may be equal to or less than 2 mm, such as in the range of, for example, 0.2-2 mm. Therefore, in an embodiment, the light source comprises a solid-state light source. In addition, in a specific embodiment, the light source comprises a chip-scale packaged LED. In this article, the term "light source" may also particularly refer to a small solid-state light source, such as having a small size or a micro size. For example, the light source may include one or more of a small LED and a micro LED. In particular, in an embodiment, the light source comprises a micro LED or a "micro LED" or a "μLED". In this article, the term "small size" or "small LED" particularly indicates a solid-state light source having a size selected from the range of 100 μm-1 mm (such as a die size, in particular a length and a width). In the present context, the term "μ-size" or "micro-LED" particularly denotes a solid-state light source having dimensions, such as die dimensions, in particular length and width, selected from the range of 100 μm and smaller.

[0094] The light source may have a light escape surface. With reference to a conventional light source, such as a light bulb or a fluorescent lamp, this may be the outer surface of a glass or quartz housing. For an LED, this may be, for example, the LED die, or the outer surface of a resin when the resin is applied to the LED die. In principle, it may also be the end of an optical fiber. The term escape surface particularly relates to a part of the light source, where light actually leaves or escapes from the light source. The light source is configured to provide a light beam. The light beam (therefore) escapes from the light exit surface of the light source.

[0095] Likewise, the light generating device may comprise a light escape surface, such as an end window. Furthermore, likewise, the light generating system may comprise a light escape surface, such as an end window.

[0096] The term "light source" may refer to a semiconductor light emitting device, such as a light emitting diode (LED), a resonant cavity light emitting diode (RCLED), a vertical cavity laser diode (VCSEL), an edge emitting laser, etc. The term "light source" may also refer to an organic light emitting diode (OLED), such as a passive matrix organic light emitting diode (PMOLED) or an active matrix organic light emitting diode (AMOLED). In a specific embodiment, the light source includes a solid-state light source (such as an LED or a laser diode). In one embodiment, the light source includes an LED (light emitting diode). The term "light source" or "solid-state light source" may also refer to a superluminescent diode (SLED).

[0097] The term LED may also refer to a plurality of LEDs.

[0098] The term "light source" may also relate to a plurality of (substantially identical (or different)) light sources, such as 2-2000 solid-state light sources. In an embodiment, the light source may comprise one or more micro-optical elements (micro-lens arrays) downstream of a single solid-state light source (such as an LED) or downstream of a plurality of solid-state light sources (i.e., for example shared by a plurality of LEDs). In an embodiment, the light source may comprise an LED with on-chip optics. In an embodiment, the light source comprises a pixelated single LED (with or without optics) (on-chip beam control is provided in an embodiment).

[0099] In an embodiment, the light source may be configured to provide primary radiation, which is used as such, such as, for example: a blue light source, such as a blue LED; or a green light source, such as a green LED; and a red light source, such as a red LED. Such LEDs that may not include a luminescent material ("phosphor") may be denoted as direct color LEDs.

[0100] However, in other embodiments, the light source may be configured to provide primary radiation, and a portion of the primary radiation is converted into secondary radiation. The secondary radiation may be based on the conversion of the luminescent material. The secondary radiation may therefore also be indicated as luminescent material radiation. In an embodiment, the luminescent material may be included by the light source, such as an LED having a luminescent material layer or a dome including luminescent material. Such an LED may be represented as a phosphor conversion LED or a PC LED (phosphor conversion LED). In other embodiments, the luminescent material may be configured at a distance ("far away") from the light source, such as an LED having a luminescent material layer that is not in physical contact with the die of the LED. Therefore, in a specific embodiment, the light source may be a light source that emits at least light of a wavelength selected from the range of 380-470nm during operation. However, other wavelengths may also be possible. This light may be partially used by the luminescent material.

[0101] In an embodiment, the light generating device may include a luminescent material. In an embodiment, the light generating device may include a PCLED. In other embodiments, the light generating device may include a direct LED (i.e., without a phosphor). In an embodiment, the light generating device may include a laser device, such as a laser diode. In an embodiment, the light generating device may include a super luminescent diode. Thus, in a specific embodiment, the light source may be selected from the group of a laser diode and a super luminescent diode. In other embodiments, the light source may include an LED.

[0102] The light source may in particular be configured to generate a source light having an optical axis (O) (beam shape) and a spectral power distribution. In an embodiment, the source light may comprise one or more bands having a known bandwidth of the laser.

[0103] The term "light source" may (thus) refer to such a light generating element, such as, for example, a solid-state light source, or, for example, to a package of a light generating element (such as a solid-state light source) and one or more elements comprising luminescent material and (other) optics (such as lenses, collimators). A light converter element ("converter element" or "converter") may comprise an element comprising luminescent material. For example, a solid-state light source like a blue LED is a light source. A combination of a solid-state light source (as a light generating element) and a light converter element (such as a blue LED and a light converter element) optically coupled to the solid-state light source may also be a light source (but may also be denoted as a light generating device). Thus, a white LED is a light source (but may, for example, also be denoted as a (white) light generating device).

[0104] The term "light source" herein may also refer to light sources including solid state light sources, such as LEDs or laser diodes or super luminescent diodes.

[0105] In embodiments, the term "light source" may (therefore) also refer to light sources that are (also) based on light conversion, such as light sources in combination with luminescent converter materials. Thus, the term "light source" may also refer to a combination of an LED and a luminescent material configured to convert at least part of the LED radiation, or to a combination of a (diode) laser and a luminescent material configured to convert at least part of the (diode) laser radiation.

[0106] In an embodiment, the term "light source" may also refer to a combination of a light source (such as an LED) and a filter, which may change the spectral power distribution of the light generated by the light source. In particular, the term "light generating device" may be used to refer to a light source as well as additional (optical components) such as filters and / or beam shaping elements, etc.

[0107] In an embodiment, the phrase "different light sources" or "multiple different light sources" and similar phrases may refer to multiple solid-state light sources selected from at least two different bins. Similarly, the phrase "same light source" or "multiple same light sources" and similar phrases may refer to multiple solid-state light sources selected from the same bin in an embodiment.

[0108] The terms "solid-state light source" or "solid-state material light source" and similar terms may particularly refer to semiconductor light sources, such as light emitting diodes (LEDs), diode lasers or superluminescent diodes.

[0109] The term "centroid wavelength" (also denoted λc) is known in the art and refers to the wavelength value at which half of the light energy is at shorter wavelengths and half of the energy is at longer wavelengths; the value is in nanometers (nm). It is this wavelength that divides the integral of the spectral power distribution into two equal parts, as represented by the formula λc = Σλ*I(λ) / (ΣI(λ)), where the sum is over the wavelength range of interest and I(λ) is the spectral energy density (i.e., the integral of the product of wavelength and intensity over the emission band normalized to the integrated intensity). The centroid wavelength can be determined, for example, under operating conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0110] Embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings, in which corresponding reference numerals indicate corresponding parts, and in which:

[0111] Figure 1A-1B Some general aspects of the light generation system are schematically depicted;

[0112] 2-4 schematically depict some other aspects of the light generating system;

[0113] FIG5 schematically depicts some detailed aspects of an embodiment; and

[0114] Figure 6 The application of the present invention is schematically depicted.

[0115] The schematic drawings are not necessarily to scale. DETAILED DESCRIPTION

[0116] FIG. 1a schematically depicts a cross section of a light generating system 1000 including a housing unit 400 and a first light generating device 110. The first light generating device 110 may be configured to generate a first device light 111. In an embodiment, the first device light 111 may include visible light, wherein the visible light may include at least blue light. The depicted housing unit 400 includes a housing wall 420 and a housing window 430 that encloses a housing space 410. In particular, the housing wall 420 may be configured to absorb at least a portion of the first device light 111 that reaches the housing wall 420 (indicated here by a cross). In a specific embodiment, the housing wall 420 may be black. In this way, the internal workings of the housing unit are not visible to an observer. In particular, the housing window 430 may be translucent for the first device light 111 and may scatter at least a portion of the blue light, as indicated by the arrow. In an embodiment, the first light generating device 110 and the housing unit 400 may be configured such that the first device light 111 may be provided in the housing space 410, and a portion of the first device light 111 may escape from the housing space 410 via the housing window 430. The portion of the first device light 111 that escapes from the housing space 410 may be defined as system light 1001 that may be observed by an observer.

[0117] FIG. 1 b schematically depicts an embodiment of the invention, wherein one or more objects 440 may be arranged in a housing space 410. The one or more objects may be configured to reflect at least a portion of the first device light 111 reaching the one or more objects 440. In the depicted embodiment, the housing unit 400, the first light generating device 110 and the one or more objects 440 are configured such that at least a portion of the first device light 111 reaching the one or more objects 440 reaches the one or more objects 440 only via reflection at the housing window 430. In an embodiment, the light generating system may include a control system 300. In particular, the control system 300 may be configured to control the first light generating device 110 depending on one or more of an input signal of a user interface, a sensor signal (of a sensor) and a timer. In a further embodiment, the first light generating device 110 may have a controllable spectral power distribution of the first device light 111. The controllable spectral power distribution of the first device light 111 may in particular include one or more different spectral power distributions of white type light. The housing unit 420 of the depicted embodiment comprises a first blocking element 450. The first blocking element 450 will be further described with reference to FIG. 2 a.

[0118] In the depicted embodiment, at least one object 440 has a cloud shape. In other embodiments, at least one object 440 may include a ball of wool (such as cotton wool), glass wool, metal wool, plastic wool, shredded paper, shredded fabric, shredded metal foil, or a fiber mat.

[0119] Figures 1a and 1b further depict a first device light 111 having a first optical axis (O1). In particular, the first optical axis (O1) and the housing window 430 have a common first angle (α1). In an embodiment, the first angle (α1) can be selected from a range of 5-85°, such as 10-80°, such as 15-75°. In a specific embodiment, the first light generating device 110 and the housing window 430 can be configured so that (i) at least 20% of the spectral power (in the visible light wavelength range) of the first device light 111 reaching the housing window 430 can be transmitted through the housing window 430, and (ii) at least 20% of the spectral power (in the visible light wavelength range) of the first device light 111 reaching the housing window 430 can be reflected by the housing window 430.

[0120] FIG2a schematically depicts an embodiment of the light generating system 1000, wherein the housing unit 400 further comprises a first blocking element 450. The first blocking element 450 may in particular be arranged between the first light generating device 110 and the one or more objects 440, and is arranged to prevent direct illumination of the one or more objects 440 with at least a portion of the first device light 111. In a specific embodiment, the first light generating device 110 and the first blocking element 450 may be arranged such that less than 5% of the total spectral power (in the visible wavelength range) of the first device light 111 reaching the one or more objects 440 is direct light, and at least 95% of the total spectral power (in the visible wavelength range) of the first device light 111 reaching the one or more objects 440 is indirect light. In the depicted embodiment, the light generating system 1000 further comprises a first grid 460 arranged downstream of the housing window 430. In an alternative embodiment, the first grid 460 may be arranged directly upstream of the housing window 430. First grid 460 includes first grid structure 461 and first grid openings 462 defined by first grid structure 461, see Fig. 5b for more details. First grid structure 461 may be specifically configured to block a portion of first device light 111, and first grid openings 462 may be specifically configured to allow first device light 111 to propagate through.

[0121] FIG2 b schematically depicts an embodiment of the light generating system 1000, which further comprises a second light generating device 120. The second light generating device 120 may be particularly configured to generate a second device light 121 comprising visible light. In an embodiment, the second light generating device 120 and the housing unit 400 may be configured such that the second device light 121 is provided in the housing space 410 and a portion of the second device light 121 escapes from the housing space 410 via the housing window 430. In an embodiment, the second light generating device 120 may have a controllable spectral power distribution of the second device light 121, which comprises one or more spectral power distributions of white light. In a further embodiment, the housing unit 400, the second light generating device 120 and the one or more objects 440 may be configured such that at least a portion of the second device light 121 that reaches the one or more objects 440 only reaches the one or more objects 440 directly. In an embodiment, the second light generating device 120 and the housing window 430 can be configured so that at least 20% of the spectral power (in the visible light wavelength range) of the second device light 121 reaching the housing window 430 is transmitted through the housing window 430, and at least 20% of the spectral power (in the visible light wavelength range) of the second device light 121 reaching the housing window 430 is reflected by the housing window 430. In a specific embodiment in which the light generating system 1000 includes the second light generating device 120 and the first grid 460, the first grid structure 461 can also be configured to block a portion of the second device light 121, and the first grid opening 462 can be configured to also allow the second device light 111 to propagate through. As described above, the light generating system can further include a control system 300. In a specific embodiment, the control system 300 is configured to control the first light generating device 110 and the second light generating device 120 depending on one or more of an input signal of a user interface, a sensor signal (of a sensor), and a timer.

[0122] FIG3a schematically depicts an alternative configuration in which the first light generating device is configured such that the first device light 111 can leave the housing space 410 only after being reflected by the reflector 425. The reflector 425 can include a mirror or a metal surface. In this way, a larger portion of the first device light 111 that reaches one or more objects 440 can be indirect light. In the depicted embodiment, the second light generating device 120 is configured to provide direct second device light 121 to one or more objects. In a specific embodiment, the housing unit 400, the second light generating device 120, and the one or more objects 440 can be configured such that at least 60% of the total spectral power (in the visible light wavelength range) of the second device light 121 that reaches the one or more objects 440 is direct light, and less than 40% of the total spectral power (in the visible light wavelength range) of the second device light 111 that reaches the one or more objects 440 is indirect light.

[0123] Fig. 3b schematically depicts an embodiment of the light generating system 1000, wherein the light generating system 1000 further comprises a first actuator 481. In such an embodiment, at least one of the one or more objects 440 may be configured to be movable in the housing 410. In particular, the first actuator 481 may be configured to move at least one of the one or more objects 440 within the housing 410, wherein the control system 300 is configured to control the first actuator 481 depending on one or more of an input signal of a user interface, a sensor signal (of a sensor), and a timer.

[0124] 4a and 4b schematically depict an embodiment in which one or more of the following apply to one or more objects 440: (i) at least one object 440 is irregularly shaped, and (ii) three or more objects are not arranged in a regular pattern. In the depicted embodiment, the light generating system 1000 further includes a second grid 490 and a second actuator 482. The second grid 490 is specifically configured to be movable in the housing 410. During operation, in an embodiment, the second grid 490 can be configured upstream of the housing window 430 and downstream of the one or more objects 440 at least part of the time. In particular, the second grid 490 can include a second grid structure 491 and a second grid opening 492 (defined by the second grid structure 491). The second grid structure 491 can be specifically configured to block a portion of the first device light 111 reflected at the one or more objects 440, and the second grid opening 492 can be specifically configured to allow a portion of the first device light 111 reflected at the one or more objects 440 to propagate through. In an embodiment, the second actuator 482 may be configured to move the second grid 490 within the housing space 410. In particular, the control system 300 may be configured to control the second grid 490 depending on one or more of an input signal of a user interface, a sensor signal (of a sensor), and a timer.

[0125] FIG. 4 b schematically depicts an embodiment, wherein the light generating system of FIG. 4 a further comprises a first grid 460 .

[0126] 5a schematically depicts a detailed embodiment of a light generating system 1000, wherein a housing window 430 comprises nanoparticles 435 having one or more sizes selected from the range of 20-240 nm, more particularly 40-180 nm, such as in the range of 60-150 nm, particularly selected from the range of 90-120 nm. The particle size may be defined by a minimum rectangular prism that confines the respective particle, wherein such rectangular prism has a length D1, a width D2, and a height D3. Additionally or alternatively, the particle size may be defined by an equivalent spherical diameter D. In a specific embodiment, the light generating system 1000 may further include a diffuser 470 configured downstream of the housing window 430 (relative to the propagation of the first device light 111). In an alternative embodiment, the light generating system 1000 may further include a diffuser 470 configured directly upstream of the housing window 430 (relative to the propagation of the first device light 111). In particular, diffuser 470 can be configured to diffusely transmit at least a portion of first device light 111 and optional second device light 121 that reaches diffuser 470. Such a diffuser can enhance the user experience by changing the focus area as the distance from housing window 430 changes.

[0127] FIG5 b schematically depicts an embodiment of a first grid 460. The first grid 460 includes a first grid structure 461 and a first grid opening 462 defined by the first grid structure 461. The first grid structure 461 may be specifically configured to block a portion of the first (and optionally second) device light 111. The first grid opening 462 may be specifically configured to allow the first (and optionally second) device light 111 to propagate through. In embodiments, the first grid structure 461 and the first grid opening 462 may have any shape.

[0128] Figure 6 A light generating system 1000 is schematically depicted as being configured in a space 1300. In particular, the space 1300 may include one or more of a floor 1305, a wall 1307, and a ceiling 1310. In the depicted embodiment, the space 1300 further includes the light generating system 1000. The light generating system 1000 may be suspended from the ceiling 1310 and attached to one or more of the walls 1307. In the depicted embodiment, the light generating system 1000 includes an array of light generating units 1100. The light generating units may have a length L1 and a width L3. The space may further include one or more of a control system 300, a user interface 301, and a sensor 310. Reference numeral 301 indicates a user interface, which may be functionally coupled with the control system 300, which is included by the light generating system 1000 or is functionally coupled to the light generating system 1000. In an embodiment, the space 1300 may include an office, a reception area, a house, a station, or a vehicle.

[0129] The term "plurality" means two or more.

[0130] Those skilled in the art will understand the terms "substantially" or "essentially" and similar terms herein. The terms "substantially" or "essentially" may also include embodiments with "completely", "completely", "all", etc. Therefore, in embodiments, the adjectives substantially or substantially may also be removed. Where applicable, the terms "substantially" or "essentially" may also relate to 90% or higher, such as 95% or higher, particularly 99% or higher, even more particularly 99.5% or higher, including 100%.

[0131] The term "comprising" also includes embodiments in which the term "comprising" means "consisting of.

[0132] The term "and / or" specifically refers to one or more of the items mentioned before and after "and / or". For example, the phrase "item 1 and / or item 2" and similar phrases may refer to one or more of item 1 and item 2. The term "comprising" may mean "consisting of" in one embodiment, but may also mean "including at least the defined categories and optionally one or more other categories" in another embodiment.

[0133] In addition, the terms first, second, third, etc. in the specification and claims are used to distinguish between similar elements and not necessarily to describe a sequential or temporal order. It should be understood that the terms so used are interchangeable under appropriate circumstances, and that the embodiments of the invention described herein are capable of operation in other sequences than those described or illustrated herein.

[0134] During operation, an apparatus, device or system may be described herein - among other things. As will be clear to one skilled in the art, the present invention is not limited to methods of operation, or apparatus, devices or systems in operation.

[0135] It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims.

[0136] In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

[0137] The use of the verb "comprise" and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. Unless the context clearly requires otherwise, throughout the specification and claims, the words "comprises," "comprising," etc. should be interpreted in an inclusive sense, rather than an exclusive or exhaustive sense; that is, in the sense of "including but not limited to."

[0138] The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

[0139] The invention may be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In a device claim, or an apparatus claim, or a system claim enumerating several components, several of these components may be embodied by the same item of hardware. The mere fact that certain measures are cited in mutually different dependent claims does not indicate that a combination of these measures cannot be used advantageously. In yet another aspect, the invention (therefore) provides a software product which, when run on a computer, is capable of implementing (one or more embodiments of) the method as described herein.

[0140] The present invention also provides a control system that can control a device, apparatus or system, or can perform the method or process described herein. Still further, the present invention also provides a computer program product that, when functionally coupled to a device, apparatus or system or run on a computer included in the device, apparatus or system, controls one or more controllable elements of such a device, apparatus or system.

[0141] The present invention further applies to an apparatus, device or system comprising one or more characterizing features described in the specification and / or shown in the attached drawings. The present invention further relates to a method or process comprising one or more characterizing features described in the specification and / or shown in the attached drawings.

[0142] The various aspects discussed in this patent can be combined to provide additional advantages. In addition, those skilled in the art will appreciate that the embodiments can be combined, and more than two embodiments can also be combined. In addition, some features can form the basis of one or more divisional applications.

Claims

1. A light generating system (1000) comprising a housing unit (400), a first light generating device (110) and one or more objects (440), wherein: - the first light generating device (110) is configured to generate a first device light (111) comprising visible light, wherein the visible light comprises at least blue light; - the housing unit (400) comprises a housing wall (420) and a housing window (430) enclosing the housing space (410); wherein the housing wall (420) is configured to absorb at least a portion of the first device light (111) reaching the housing wall (420); and wherein the housing window (430) is translucent to the first device light (111) and scatters at least a portion of the blue light; - the first light generating device (110) and the housing unit (400) are configured such that (i) the first device light (111) is provided in the housing space (410), and (ii) a portion of the first device light (111) escapes from the housing space (410) via the housing window (430); - one or more objects (440) are arranged in the housing space (410) and are arranged to reflect at least a portion of the first device light (111) reaching the one or more objects (440); - the housing unit (400), the first light generating device (110) and the one or more objects (440) are configured such that at least a portion of the first device light (111) reaching the one or more objects (440) reaches the one or more objects (440) only via reflection at the housing window (430); and - wherein the housing unit (400) further comprises a first blocking element (450), the first blocking element (450) being arranged between the first light generating device (110) and the one or more objects (440), and being arranged to prevent direct illumination of the one or more objects (440) with at least a portion of the first device light (111).

2. The light generating system (1000) of claim 1, wherein the housing window (430) comprises nanoparticles (435) having one or more sizes selected from the range of 40-180 nm, and wherein the first device light (111) comprises white type light; and wherein the housing wall (420) is black.

3. The light generating system (1000) according to any one of the preceding claims, wherein the first blocking element (450) absorbs at least 50% of the first device light that reaches the first blocking element perpendicularly.

4. A light generating system (1000) according to any of the preceding claims, wherein the first device light (111) has a first optical axis (O1), wherein the first optical axis (O1) and the housing window (430) have a common first angle (α1), wherein the first angle (α1) is selected from the range of 10-80°.

5. A light generating system (1000) according to any of the preceding claims, wherein the first light generating device (110) and the housing window (430) are configured such that (i) at least 20% of the spectral power of the first device light (111) reaching the housing window (430) is transmitted through the housing window (430), and (ii) at least 20% of the spectral power of the first device light (111) reaching the housing window (430) is reflected by the housing window (430).

6. A light generating system (1000) according to any of the preceding claims, wherein for one or more objects (440) one or more of the following applies: (i) at least one of the objects (440) is irregularly shaped, and (ii) three or more objects are not arranged in a regular pattern.

7. The light generating system (1000) according to any of the preceding claims, wherein at least one of the objects (440) has the shape of a cloud.

8. The light generating system (1000) of any one of the preceding claims, wherein at least one of the objects (440) comprises a ball of lint, shredded paper, shredded fabric, shredded metal foil, or a fiber mat.

9. A light generating system (1000) according to any of the preceding claims, wherein the first light generating device (110) has a controllable spectral power distribution of the first device light (111), which includes one or more different spectral power distributions of white type light; wherein the light generating system (1000) further includes a control system (300), wherein the control system (300) is configured to control the first light generating device (110) depending on one or more of an input signal of a user interface, a sensor signal and a timer.

10. The light generating system (1000) according to any one of the preceding claims, further comprising a second light generating device (120), wherein: - the second light generating device (120) is configured to generate a second device light (121) comprising visible light; - the second light generating device (120) and the housing unit (400) are configured such that (i) the second device light (121) is provided in the housing space (410), and (ii) a portion of the second device light (121) escapes from the housing space (410) via the housing window (430); as well as The housing unit (400), the second light generating device (120) and the one or more objects (440) are configured such that at least a portion of the second device light (121) reaching the one or more objects (440) only reaches the one or more objects (440) directly.

11. The light generating system (1000) according to any of the preceding claims, further comprising a first grid (460) configured downstream of the housing window (430) or directly upstream of the housing window (430), wherein the first grid (460) comprises a first grid structure (461) and a first grid opening (462), wherein the first grid structure (461) is configured to block a portion of the first device light (111), and wherein the first grid opening (462) is configured to allow the first device light (111) to propagate through.

12. The light generating system (1000) according to any of the preceding claims, further comprising a diffuser (470) arranged downstream of the housing window (430) or directly upstream of the housing window (430), the diffuser (470) being configured to diffusely transmit at least a portion of the first device light (111) reaching the diffuser (470).

13. The light generating system (1000) according to any one of the preceding claims, further comprising a first actuator (481), wherein: - at least one of the one or more objects (440) is configured to be movable within the housing (410); as well as - A first actuator (481) is configured to move at least one of the one or more objects (440) within the housing (410).

14. The light generating system (1000) according to any of the preceding claims, further comprising a second grid (490) and a second actuator (482), and a control system (300), wherein: - the second grid (490) is configured to be movable in the housing (410); - during operation, at least part of the time the second grid (490) is arranged upstream of the housing window (430) and downstream of the one or more objects (440); - the second grid (490) comprises a second grid structure (491) and a second grid opening (492), wherein the second grid structure (491) is configured to block a portion of the first device light (111) reflected at the one or more objects (440), and wherein the second grid opening (492) is configured to allow a portion of the first device light (111) reflected at the one or more objects (440) to propagate therethrough; - a second actuator (482) configured to move a second grid (490) within the housing (410); and - the control system (300) is configured to control the second grid (490) depending on one or more of an input signal of a user interface, a sensor signal and a timer.

15. A space (1300) comprising a ceiling (1310), wherein the space (1300) further comprises a light generating system (1000) according to any one of the preceding claims suspended from the ceiling (1310).

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