Light generating system comprising a skylight module

Abstract

The invention provides a light generating system (1000) comprising a lighting module (1500), wherein the lighting module (1500) comprises a skylight module; wherein the lighting module (1500) comprises one or more light generating devices (100), a first light escape area (1510), a second light escape area (1520), and a light escape area (1530); wherein: the one or more light generating devices (100) are configured to generate device light (101); the first light escape area (1510) and the second light escape area (1520) are configured under a mutual angle (α) selected from the range of 30-150°; wherein a first distance (d1) between the first light escape area (1510) and the third light escape area (1530) is at least partly bridged by the second light escape area (1520); wherein the light generating system (1000) comprises a system end window (1010), wherein the system end window (1010) comprises the third light escape area (1530); the light generating system (1000) is configured such that in a first operational mode the light generating system (1000) provides first module light (1511) and second module light (1512), wherein the first module light (1511) comprises a first part of the device light (101) that propagates from the first light escape area (1510) and through the third light escape area (1530), and wherein the second module light (1521) comprises a second part of the device light (101) that propagates from the second light escape area (1520) and through the third light escape area (1530); wherein the first module light (1511) is white light, and wherein the first module light (1511) and the second module light (1521) differ in one or more of (i) color point and homogeneity of the light (1511,1522) over the respective light escape area (1510,1520).

Description

[0001] LIGHT GENERATING SYSTEM COMPRISING A SKYLIGHT MODULE

[0002] FIELD OF THE INVENTION

[0003] The invention relates to a light generating system. The invention further relates to an indoor space comprises the light generating system.

[0004] BACKGROUND OF THE INVENTION

[0005] Light generating systems are known in the art. For instance, US2020370719A1 describes a lighting fixture appearing as a skylight and referred to as a skylight fixture. The skylight fixture has a sky-resembling assembly and a plurality of sunresembling assemblies. The sky-resembling assembly has a sky-resembling optical assembly and a sky-specific light source, wherein light from the sky-specific light source exits a planar interior surface of the sky -resembling light optical assembly as skylight light. The plurality of sun-resembling assemblies are arranged adjacent one another and extend downward from a periphery of the sky-resembling assembly. Each of the plurality of sun-resembling assemblies has a sun-resembling optical assembly and a sun-specific light source, wherein light from the sun-specific light source exits a planar interior surface of the sun-resembling optical assembly as sunlight light.

[0006] US20220026052A1 and WO2019156950A1 both disclose a ceiling skylight fixture providing skylight from a horizontally extending surface and providing sunlight from vertically extending surfaces.

[0007] US20180017233A1 discloses a lighting apparatus capable of emitting light imitating the sky in nature.

[0008] SUMMARY OF THE INVENTION

[0009] Artificial skylights may artificially reproduce the visual experience of having the sky and sun in an indoor setting. In particular, artificial skylights may provide the experience of having a skylight through which the sky, sun, and clouds, et cetera, can be seen. Generally, a sky mimicking light source is arranged recessed with respect to the front face of a device, i.e. with respect to the light exit window, and the inner side walls of the recessed cavity provide sunlight light mimicking faces. A first challenge associated with the artificial skylights of the prior art is to provide each observer with a satisfactory view at the sun and the sky, no matter the viewing direction. However, not all side walls can be sun struck at the same time without compromising on the illusion of solar direction and solar shadow. Thus the user experience may be degraded for the users only observing the shadow portion of the skylight. Secondly, at some distance from the artificial light, users can no longer see the sky. Only the sun struck inner sidewalls remain, which may reduce the light scene experience considerably. And, although a much larger skylight could offer some relief, professional spaces are often bound to grid ceilings of standardized dimensions. Further, a plurality of smaller sized skylights conveys a much stronger illusion than a single large-sized skylight. Further, whereas an actual skylight may provide a view on natural and / or man-made structures in the vicinity, e.g., a tree, a mountain, a bridge, or a church, artificial skylights of the prior art may typically be limited to the sky and sun, which may detrimentally affect the illusion, i.e., artificial skylights of the prior art may lack a scenery experience. A further challenge of the prior art relates to the so-called blue light wash, which originates from the blue light emission of the sky building elements, and which may turn a (work)space excessively blue. Although vertically arranged sun mimicking sidewalls may in principle help to reduce the effect, efficient (wall to wall rather than wall to desk) and sufficient compensation (too little area) may typically be hampered due to high glare (bright sun). Furthermore, it would preferably take four sun lit inner sidewalls for a square or rectangular skylight to balance the effect evenly. But again, when all four sidewalls are sunstruck the illusion does not feel natural in that the illusion of solar direction and solar shadow is lost. Furthermore, for a more natural look / sense of the artificial skylight it is preferred that the recessed cavity of the artificial skylight is free from a (collimating) raster structure or louver structure. Moreover, the absence of such structures renders the artificial skylight to be more efficient as these structures typically block and / or absorb light issued by the light sources of the artificial skylight.

[0010] Hence, it is an aspect of the invention to provide an alternative light generating system, which preferably further at least partly obviates one or more of above-described drawbacks. The present invention may have as object to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative. The invention is set out in the appended set of claims.

[0011] According to a first aspect, the invention provides a light generating system comprising a lighting module, wherein the lighting module comprises a skylight module. The lighting module may comprise one or more light generating devices, a first light escape area, a second light escape area, and / or a third light escape area. In embodiments, the one or more light generating devices may be configured to generate device light. In further embodiments, the first light escape area and the second light escape area may be configured under a mutual angle a selected from the range of 30-150°. Further, in embodiments, a first distance dl between the first light escape area and the third light escape area may be at least partly bridged by the second light escape area. The light generating system may further comprise a system end window, especially wherein the system end window comprises the third light escape area. In embodiments, the light generating system may be configured such that in a first operational mode (of the light generating system) the light generating system provides first module light and second module light. Especially, the first module light may comprise a first part of the device light that propagates from the first light escape area and through the third light escape area, especially wherein the first module light is white light. Similarly, in embodiments, the second module light may comprise a second part of the device light that propagates from the second light escape area and through the third light escape area. In further embodiments, the first module light and the second module light may differ in one or more of (i) color point and (ii) homogeneity of the light over the respective light escape area. In specific embodiments, the invention may provide a light generating system comprising a lighting module, wherein the lighting module comprises a skylight module; wherein the lighting module comprises one or more light generating devices, a first light escape area, a second light escape area, and a third light escape area; wherein: the one or more light generating devices are configured to generate device light; the first light escape area and the second light escape area are configured under a mutual angle (a) selected from the range of 30-150°; wherein a first distance (dl) between the first light escape area and the third light escape area is at least partly bridged by the second light escape area; wherein the light generating system comprises a system end window, wherein the system end window comprises the third light escape area; the light generating system is configured such that, when coupled to a ceiling or a recessed ceiling, in a first operational mode (of the light generating system) the light generating system to provide in a vertical direction first module light representing sunlight and to provide in a horizontal direction second module light representing skylight, wherein the first module light comprises a first part of the device light that propagates from the first light escape area and through the third light escape area, and wherein the second module light comprises a second part of the device light that propagates through and from the second light escape area and through the third light escape area; wherein the first module light is white light, and wherein the first module light and the second module light differ in one or more of (i) color point and (ii) homogeneity of the light over the respective light escape area.

[0012] Such embodiments may provide the advantage that the artificial sun is presented on an (essentially) level surface, and wherein the artificial sky is presented on the side surfaces, thereby providing a similar experience for different viewing directions, i.e., as the artificial sun is arranged centrally, a more homogeneous lighting experience can be provided. In particular, the artificial skylight of the invention may offer the same light scene experience of the sky and sun independent of the observation direction. Also, the lighting device may integrate a functional light source (the roof building sunlight light source) with a symmetric arrangement of skylight light sources (or “windows”), in one package. And, particularly in embodiments with window symmetry, the blue-light wash may be reduced substantially and evenly. Besides that, the sky mimicking windows may still be observable at a distance, which may substantially improve the artificial skylight illusion. Yet further, a sunrise and sunset may also be enabled and be observable through the windows and closer to the horizon, rather than just serving a user with a view into space (e.g. a blue sky).

[0013] Hence, the invention provides: a horizontal arranged sunlight mimicking light source arranged in a recess and configured to provide first module light through the first light escape area; vertical arranged skylight light sources arranged downstream of the sunlight light source and configured to provide second module light through the second light escape area, building part of the inner sidewalls of the recess; a transparent panel or open space arranged downstream of the skylight light source(s) building the inner surfaces of the inner cavity - aka windows. Typically, the sunlight light source emitting light of a warmer CCT (1800 - 6000 K) and a skylight mimicking light source providing light of a colder CCT (6500 - 20000 K) or blue light. Optionally, the invention may further provide a series of roof supporting elements (or “’sun’ supporting elements” ), such as beams, connecting the base of the device with the sunlight mimicking element, such as window frames, thus strengthening the illusion by representing structural integrity. Yet further, the invention may optionally provide opaque roof supporting elements (for example first and / or second beams) enhancing and providing the illusion of solar direct and solar shadows, for example, by means of back illumination or by paints or coatings of different shades of white.

[0014] As mentioned before, in embodiments, the invention provides a light generating system comprising a lighting module. In embodiments, the lighting module light may provide light that mimics the natural light observed on a clear day. This may especially comprise a combination of both blue light which results from the scattering of sunlight in the atmosphere, and white light which may simulate direct sunlight. Alternatively, in embodiments, the lighting module may provide a combination of white light of two different color temperatures. Hence, in embodiments, the lighting module may provide light that simulates such natural skylight. Further, in specific embodiments the lighting module may provide light that mimics the natural light observed during a cloudy day, or during sunset or sunrise.

[0015] Herein, the lighting module may especially comprise a skylight module, i.e. a lighting module to be functionally coupled to a (suspended) ceiling. However, other applications, like an artificial window, functionally coupled to a wall, are herein also encompassed. For instance, the artificial skylight may be mounted (exactly) in the corners of a space, thereby doubling as a vertical window Hence, the term “lighting module” may in embodiments refer to an artificial skylight (and may in other specific embodiments refer to another type of lighting module). Especially, the term “skylight module” (which may also be indicated as “artificial sky light”) may in embodiments be a window-like artificial light generating device. Such artificial skylight may form e.g. part of a ceiling (or roof) (of a building) or may be functionally coupled (e.g., physically connected) to the ceiling (or roof), e.g. for mimicking daylight. The term “ceiling” may herein also refer to a suspended ceiling.

[0016] In embodiments, the lighting module may comprise a first light escape area, a second light escape area, and a third light escape area.

[0017] In further embodiments, the first light escape area and the second light escape area may be arranged recessed relative to a (suspended) ceiling, whereas the third light escape area may especially be arranged in-plane with the ceiling. The first light escape area and the third light escape area may especially be arranged opposite to one another, particularly wherein a first distance dl between the first light escape area and the third light escape area is at least partly bridged by the second light escape area. In further embodiments, the first light escape area and the second light escape area may be configured under a mutual angle a selected from the range of 30-150°, i.e., the first light escape area may define a first plane and the second light escape area may define a second plane, wherein the first plane and the second plane are arranged at an angle a selected from the range of 30-150°. In particular, in embodiments, the second light escape area may comprise a plurality of second area parts, wherein each second area part defines a second plane having an (independently selected) angle a selected from the range of 30-150° to the first plane. Especially, the mutual angle a may be selected from the range of 50-130°, such as from the range of 70-110°. In embodiments, the mutual angle a may be (about) 90°, i.e., the first and the second light escape areas may be arranged at (about) a right angle. However, in further embodiments, la- 900! - 5°, such as > 10°, especially > 20°, i.e., the first and the second light escape areas may be arranged at an oblique angle, especially an acute angle, or especially an obtuse angle.

[0018] Similarly, in embodiments, the third light escape area and the second light escape area may be configured under a mutual angle a2 selected from the range of 30-150°, i.e., the third light escape area may define a third plane and the second light escape area may define a second plane, wherein the third plane and the second plane are arranged at an angle a2 selected from the range of 30-150°. In particular, in embodiments, the second light escape area may comprise a plurality of second area parts, wherein each second area part defines a second plane having an (independently selected) angle a2 selected from the range of 30-150° to the third plane. Especially, the mutual angle a2 may be selected from the range of 50-130°, such as from the range of 70-110°. In embodiments, the mutual angle a2 may be (about) 90°, i.e., the third and the second light escape areas may be arranged at (about) a right angle. However, in further embodiments, |a-90°| > 5°, such as > 10°, especially > 20°, i.e., the third and the second light escape areas may be arranged at an oblique angle, especially an acute angle, or especially an obtuse angle.

[0019] In further embodiments, 160° < a + a2 < 200°, such as 170° < a + a2 < 190°, such as 175° < a + a2 < 185°. In particular, in embodiments, a and a2 may together be about 180°.

[0020] The angles a and a2 may especially correspond to the angles facing the space defined by the first, second and third light escape areas (see below).

[0021] As mentioned above, the second light escape area may bridge a first distance dl between the first light escape area and the third light escape area. In particular, the first light escape area and the third light escape area may be separated by a(n average) distance d2, wherein 0.3 < dl / d2 < 1, such as 0.4 < dl / d2 < 0.9, especially 0.5 < dl / d2 < 0.8. In further embodiments, dl / d2 > 0.5, such as > 0.6, especially > 0.7, such as > 0.8. In further embodiments, dl / d2 < 1, such as < 0.95, especially < 0.9.

[0022] In particular, the first light escape area and the third light escape area may together define opposite faces of a cavity. The second light escape area(s) may be arranged to further define the cavity. Especially, the second light escape area may at least partially overlap with a convex hull of the cavity as defined by the first and third light escape areas. In specific embodiments, the second light escape area may comprise at least 60% of a convex hull of a cavity defined by the first light escape area and the third light escape area, such as at least 80%, especially at least 90%, including 100%. In embodiments, the first light escape area and the third light escape area may have a similar area and shape. For instance, in embodiments, in a first plane parallel to the ceiling, the first light escape area may have an (average) area al and in a third plane parallel to the ceiling the third light escape area may have an (average) area a3, wherein (|al - a3|) / (0.5*(al+a3)) < 0.2, such as < 0.1, especially < 0.05, including (essentially) 0. Similarly, in embodiments, in a first plane parallel to the ceiling, the first light escape area may have a (average) aspect ratio ARI and in a third plane parallel to the ceiling the third light escape area may have an (average) aspect ratio AR3, wherein (|ARl-AR3|) / (0.5*(ARl+AR3)) < 0.2, such as < 0.1, especially < 0.05, including (essentially) 0.

[0023] It will be clear to the person skilled in the art, however, that the first light escape area and the third light escape area may also differ in area and / or shape. For instance, in embodiments, the first light escape area may have a diamond-shape, corners of which may be arranged on four second beams differing in height, while the third light escape area has a rectangular, especially square, shape.

[0024] The light generating system may, in embodiments, comprise a system end window, wherein the system end window comprises the third light escape area. In embodiments, the system end window may (essentially) be an open space, i.e., a window defined by (or “in”) the (suspended) ceiling. In further embodiments, the system end window may comprise a solid material, such as glass. The system end window may especially be transparent (for the device light). By extent, in embodiments, the third light escape area may be transparent (for the device light).

[0025] The term “transparent” with respect to a material herein refers to the property that almost all light encountering the material will pass directly through the material, i.e., the vast majority of the light is not reflected nor scattered by the material. For instance, air and glass are generally transparent.

[0026] In further embodiments, the lighting module may comprise an enclosure (or “housing”). The term “enclosure” may herein especially refer to a housing defining an internal space, wherein the internal space is at least partially enclosed by the enclosure, e.g., enclosed but for an (open) window. The enclosure may especially comprise one or more of the one or more light generating devices, the first light escape area, the second light escape area, and the third light escape area. In particular, the one or more light generating devices, the first light escape area, and the second light escape area may be arranged in the enclosure. In further embodiments, the enclosure may comprise an enclosure window, wherein the enclosure window comprises the third light escape area. Especially, the enclosure window may comprise the system end window.

[0027] In embodiments, the enclosure may especially have a dome-like or a cylindrical shape. In further embodiments, the enclosure may have a prismatic shape, especially a rectangular prismatic shape. The enclosure may especially comprise a light reflective wall, such as a diffusively reflective wall. In particular, the light reflective wall may (at least partially) define the shape of the enclosure. The interior surface of the enclosure may comprise (static) images at its surface. Further, in embodiments, an area between the second light escape area and an enclosure wall may comprise objects (or “obstructions”), especially scenery building bodies, such as (translucent) images of trees or a church for example. In such embodiments, the enclosure, or especially an interior surface of the enclosure, may be configured rotatable, thereby allowing for the illusion of moving bodies, such as clouds.

[0028] In further embodiments, the enclosure window is an opening in the enclosure. In such embodiments, the third light escape area may essentially comprise air.

[0029] In further embodiments, the lighting module may comprise one or more light generating devices. Especially, the one or more light generating devices may be configured to generate device light. In particular, a first part of the device light may propagate from the first light escape area and through the third light escape area, whereas a second part of the device light may propagate from the second light escape area and through the third light escape area. Hence, the light generating devices may be configured to provide device light such that a first part of the device light follows a path leaving the first light escape area and passing through the third light escape area, whereas a second part of the device light follows a path leaving the second light escape area and passing through the third light escape area.

[0030] The light generating system, especially a control system comprised by the light generating system, may have an operational mode. The term “operational mode” may also be indicated as “controlling mode”. The light generating system may execute an action in a “mode” or “operational mode” or “mode of operation”. Likewise, in a method an action, stage, or step may be executed in a “mode” or “operation mode” or “mode of operation”. This does not exclude that the light generating system may also be adapted for providing another operational mode, or a plurality of other operational modes. Likewise, this does not exclude that before executing the mode and / or after executing the mode one or more other modes may be executed. However, in embodiments, a control system (see further also below) may be available, that is adapted to provide at least the operational mode. Would other modes be available, the choice of such modes may especially be executed via a user interface, though other options, like executing a mode in dependence of a sensor signal or a (time) scheme, may also be possible. The operational mode may in embodiments also refer to a light generating system that can only operate in a single operational mode (i.e. “on”, without further tunability). The term “controlling” and similar terms especially refer at least to determining the behavior or supervising the running of an element. Hence, herein “controlling” and similar terms may e.g. refer to imposing behavior to the element (determining the behavior or supervising the running of an element), etc., such as e.g. measuring, displaying, actuating, opening, shifting, changing temperature, etc.. Beyond that, the term “controlling” and similar terms may additionally include monitoring. Hence, the term “controlling” and similar terms may include imposing behavior on an element and also imposing behavior on an element and monitoring the element. The controlling of the element can be done with a control system, which may also be indicated as “controller”. The control system and the element may thus at least temporarily, or permanently, functionally be coupled. The element may comprise the control system. In embodiments, the control system and element may not be physically coupled. Control can be done via wired and / or wireless control. The term “control system” may also refer to a plurality of different control systems, which especially are functionally coupled, and of which e.g. one control system may be a master control system and one or more others may be slave control systems. A control system may comprise or may be functionally coupled to a user interface. For instance, in embodiments, the light generating system may comprise a control system, especially wherein the control system is configured to (individually) control the one or more light generating devices. For instance, the control system may be configured to control the one or more light generating devices in dependence of one or more of an input signal of a user interface, a sensor signal of a sensor, and a timer. Hence, in embodiments, the control system may control the light generating system, especially the one or more light generating devices, in dependence of 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.

[0031] In further embodiments, the control system may control the light generating system, especially the one or more light generating devices, in dependence of a (local) weather condition. In particular, the control system may control the light generating system to resemble the local weather conditions, which may further enhance the illusion of having a natural skylight. For instance, for a room having both an artificial skylight and a window, a (substantial) discrepancy between the artificial view through the skylight and the actual weather as seen through the window may be detrimental to the illusion.

[0032] In further embodiments, the light generating system may further comprise a sensor configured to sense a property of a space and to provide a related sensor signal to the control system. In such embodiments, the control system may be configured to control the light generating device, especially (individually) the one or more light generating devices, based on the sensor signal. In further embodiments, the sensor may be configured to sense presence and / or movement of a human in the space, especially presence, or especially movement, and to provide a related sensor signal to the control system. The term “related sensor signal” may herein refer to a signal that is related to the sensed property. In particular, the related sensor signal may comprise raw and / or processed data related to the sensed property, such as to the presence and / or movement of a human.

[0033] The light generating system may especially have a first operational mode, wherein in the first operational mode the light generating system provides first module light and second module light. In particular, the first module light may comprise the first part of the device light (see above), and the second module light may comprise the second part of the device light (see above). The first module light and the second module light may especially differ in one or more of (i) color point and (ii) homogeneity of the light over the respective light escape area, i.e. over the first and second light escape areas, respectively, especially at least in color point, or especially at least in homogeneity.

[0034] In particular, the first module light may correspond to the light from the first light escape area and may, in embodiments, represent sunlight. The first module light may thus especially comprise white light.

[0035] The term “white light”, and similar terms, herein, is known to the person skilled in the art. It may especially relate to light having a correlated color temperature (CCT) between about 1800 K and 20000 K, such as between 2000 and 20000 K, especially 2700- 20000 K, for general lighting especially in the range of about 2000-7000 K, such as in the range of 2700 K and 6500 K. In embodiments, the correlated color temperature (CCT) may especially be in the range of about 7000 K and 20000 K. Yet further, in embodiments the correlated color temperature (CCT) is especially within about 15 SDCM (standard deviation of color matching) from the BBL (black body locus), especially within about 10 SDCM from the BBL, even more especially within about 5 SDCM from the BBL.

[0036] In embodiments, the lighting module may comprise a first light generating device defining the first light escape area. For instance, the first light escape area may comprise a light emitting surface or a light transmissive window of the first light generating device. In particular, in such embodiments, the first light generating device may be configured to provide device light, especially white device light, to the third light escape area.

[0037] In particular, in embodiments, the one or more light generating devices may comprise a first light generating device configured to generate white first device light, wherein the light generating system is configured such that in the first operational mode (of the light generating system) at least part of the first white device light escapes from the first light escape area, such as from a light emitting surface comprising the first light escape area.

[0038] In further embodiments, the first light generating device may comprise a light transmissive window comprising a light transmissive material, wherein the light transmissive window comprises the first light escape area. In such embodiments, the first light generating device may be configured to generate the white first device light remote from the first light escape area, and to provide the white first device light to the light transmissive window, especially through the light transmissive window. Hence, the light transmissive window may especially be transmissive for (at least part of) the white first device light. Especially, the light transmissive window may be translucent for the white first device light.

[0039] The light transmissive material is known to the skilled person as a material that allows light to be transmitted through it. The light transmissive material may be transmissive to light, wherein, in embodiments, transmissivity of light through the light transmissive material in a direction perpendicular to its surface may be at least 50%, such as at least about 75%, like in embodiments at least 90%, even more especially at least about 100%.

[0040] The light transmissive material may comprise one or more materials selected from the group consisting of a transmissive organic material, such as selected from the group consisting of PE (polyethylene), PP (polypropylene), PEN (polyethylene napthalate), PC (polycarbonate), polyurethanes (PU), polymethylacrylate (PMA), polymethylmethacrylate (PMMA) (Plexiglas or Perspex), polymethacrylimide (PMI), polymethylmethacrylimide (PMMI), styrene acrylonitrile resin (SAN), cellulose acetate butyrate (CAB), silicone, polyvinylchloride (PVC), polyethylene terephthalate (PET), including in an embodiment (PETG) (glycol modified polyethylene terephthalate), PDMS (poly dimethyl siloxane), and COC (cyclo olefin copolymer). Especially, the light transmissive material may comprise an aromatic polyester, or a copolymer thereof, such as e.g. one or more of polycarbonate (PC), poly (methyl)methacrylate (P(M)MA), polyglycolide or polyglycolic acid (PGA), polylactic acid (PLA), polycaprolactone (PCL), polyethylene adipate (PEA), polyhydroxy alkanoate (PHA), polyhydroxy butyrate (PHB), poly(3-hydroxybutyrate-co-3 -hydroxy valerate) (PHBV), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), polyethylene naphthalate (PEN). Especially, the light transmissive material may comprise polyethylene terephthalate (PET). Hence, the light transmissive material is especially a polymeric light transmissive material. However, in another embodiment the light transmissive material may comprise an inorganic material. Especially, the inorganic light transmissive material may be selected from the group consisting of glasses, (fused) quartz, transmissive ceramic materials, and silicones. Also hybrid materials, comprising both inorganic and organic parts may be applied. Especially, the light transmissive material comprises one or more of PMMA, PC, or glass.

[0041] In embodiments, the light transmissive window may be translucent. Especially, the light transmissive window may be diffusive / scattering. The latter may prevent that an observer may view from external through the light exit window into the housing, while allowing light to escape from the housing. Hence, especially in embodiments the light transmissive window is not fully transparent as it appears useful when at least part of the light escaping from the system is scattered in the light transmissive window.

[0042] A relatively uniform distribution of the white first device light at the first light escape area may strengthen the sunlight illusion. Particularly, it may be undesirable that outlines of a lighting device can be seen when looking at the first light escape area. Hence, a translucent (rather than transparent) light transmissive window or a diffuse reflective element (see below) may be particularly suitable for transmitting or reflecting the white first device light.

[0043] Hence, in further embodiments, the lighting module may comprise a first light generating device configured to provide device light to the first light escape area. In such embodiments, the first light generating device may especially be arranged remote to the first light escape area. In particular, in embodiments, the lighting module may comprise a white diffuse element which is reflective or translucent for white light, wherein the white diffuse element is configured to reflect or transmit at least part of the white light of the device light. In further embodiments, the white diffuse element may comprise the first light escape area. The white diffuse element may, for instance, comprise a white diffuse layer or a white diffuse window.

[0044] The phrase “reflective for white light”, and similar phrases herein, may herein refer to a surface reflecting at least 70% of white light (under perpendicular irradiation with the white light), such as at least 80%, especially at least 90%, such as at least 95%, including 100%.

[0045] The phrase “translucent for white light”, and similar phrases herein, may herein refer to a material transmitting at least 70% of white light arriving at a surface of the material (under perpendicular irradiation with the white light), such as at least 80% (though higher values are not excluded, such as at least 90%, such as at least 95%), while at least part of the light that is transmitted may also be scattered. Hence a translucent window may transmit light and diffuse the light. A translucent window may in embodiment be milky. For instance, the first light escape area may be a surface of a translucent window. Alternatively or additionally, the second light escape area may be a surface of a translucent window.

[0046] The phrase “transparent for white light”, and similar phrases herein, may herein refer to a material transmitting at least 70% of white light arriving at a surface of the material (under perpendicular irradiation with the white light), such as at least 80%, such as at least 90%, such as at least 95%, without substantial scattering. A transparent window may especially be clear. For instance, in embodiments the third light escape area may be a surface of a transparent end window (or there may be no end window at all, and only an opening).

[0047] The white diffuse element may especially comprise an amorphous diffuser. Amorphous diffusers may be particularly suitable as these may suppress (undesired) reflections from skylight light mimicking light sources and transparent windows, at the surface of a sunlight light source. That is, it may be preferred to have as few as possible remnants of such elements visible at the surface of the sunlight light source, which may be facilitated by an amorphous diffuser. The term “amorphous diffuser” may herein refer to a diffuser having hardly any specular reflections at its surface interface at the observer side. The amorphous diffuser may essentially be devoid of crystals.

[0048] In further embodiments, the lighting module may comprise a white diffuse element, wherein the white diffuse element is reflective for white light, and wherein the white diffuse element is configured to reflect at least part of the white light of the device light. In particular, in such embodiments, (at least part of) the one or more light generating devices and the white diffuse element may be arranged such that the one or more light generating devices provide device light to the white diffuse element, wherein the device light impending on the white diffuse element is reflected towards the third light escape area.

[0049] Similarly, in embodiments, the lighting module may comprise a white diffuse element, wherein the white diffuse element is translucent for white light, and wherein the white diffuse element is configured to transmit at least part of the white light of the device light. In particular, in such embodiments, (at least part of) the one or more light generating devices and the white diffuse element may be arranged such that the one or more light generating devices provide device light to the white diffuse element, wherein the device light impending on the white diffuse element is transmitted and travels on towards the third light escape area.

[0050] As mentioned above, in embodiments, the first module light and the second module light may differ in color point. In particular, the second module light may correspond to the light from the second light escape area and may, in embodiments, represent light scattered in the sky. For instance, the second module light may comprise blue light to represent the sky during a sunny day, but may also comprise a mixture of blue and white light to represent a more cloudy or foggy day. Further, in embodiments, the second module light may comprise a gradient of, for instance, orange and or purple light to represent a sunrise or sunset. It will be clear to the person skilled in the art that many variations can be made in order to form representations of variations in the natural sky.

[0051] For instance, in embodiments, the device light may comprise blue light. The terms “blue light” or “blue emission” especially relates to light having a wavelength in the range of about 440-495 nm (including some violet and cyan hues). In embodiments, (at least part of) the one or more light generating devices may be configured to provide blue light.

[0052] In embodiments, the lighting module may comprise a second light generating device defining the second light escape area. Especially, the light generating system may be configured such that in the first operational mode (of the light generating system) at least part of the second device light escapes from the second light escape area.

[0053] For instance, the second light escape area may comprise a light emitting surface of the second light generating device. In particular, in such embodiments, the second light generating device may be configured to provide device light, especially blue device light, to the third light escape area.

[0054] In further embodiments, the lighting module may comprise a second light generating device configured to provide device light to the second light escape area. In such embodiments, the second light generating device may especially be arranged remote to the second light escape area. In such embodiments, the lighting module may especially comprise a second transparent element, wherein the second transparent element comprises the second light escape area, and wherein the second transparent element is at least transparent for blue device light. In embodiments, the second transparent element may comprise a graded filter, especially a graded filter for blue light. Thereby, a natural variation in the blue color of the sky can be reproduced, which may further strengthen the illusion. For instance, in specific embodiments, the graded filter may provide a gradient in a direction from the first towards the third light escape area, especially wherein the graded filter is configured such that a brightness of the blue light passing through the second transparent element increases in a direction from the first light escape area to the second light escape area.

[0055] In particular, the second transparent element may facilitate providing, for example, sceneries in the sky (see below). In particular, in such embodiments, (at least part of) the one or more light generating devices and the second transparent element may be arranged such that the one or more light generating devices provide device light to the second transparent element, wherein the device light impending on the second transparent element is transmitted and travels on towards the third light escape area.

[0056] It may be particularly convenient and efficient when the first module light and the second module light are provided by the same light generating device(s). Hence, in embodiments, the lighting module comprises a light transmissive window comprising a Rayleigh scatterer, wherein the light transmissive window defines the second light escape area. The Rayleigh scatterer may be configured to (selectively) scatter blue light.

[0057] In embodiments with a light transmissive window comprising a Rayleigh scatterer, the one or more light generating devices may especially be configured to provide (white) device light to the first light escape area via the second light escape area, i.e., via the Rayleigh scatterer. In particular, in such embodiments, the lighting module may especially comprise the white diffuse element (see above), wherein the white diffuse element is reflective for (at least part of) the white device light, and especially wherein the white diffuse element comprises the first light escape area and is configured to reflect the white device light received from the one or more light generating devices towards the third light escape area. Such embodiments may provide a particularly natural experience as the natural blue sky is also caused due to Rayleigh scattering of natural white sunlight. As, in such embodiments, part of the blue light is scattered by the Rayleigh scatterer, the device light arriving at the first light escape area will have lost intensity in the blue wavelength range relative to the device light as generated by the one or more light generating devices. The light generating devices may thus be configured to provide device light having a higher proportion of blue light to account for the scattering, and such that the device light arriving at the first light escape area, especially at the white diffuse element is white light. In specific embodiments, the lighting device may have a (dedicated) blue light generating device configured to provide blue device light to the Rayleigh scatterer and, optionally, to the first light escape area via the Rayleigh scatterer.

[0058] Hence, in embodiments, the first module light (escaping from the first light escape area) may comprise white light and the second module light (escaping from the second light escape area) may comprise blue light. In particular in these embodiments, the first module light may comprise white light having a first correlated color temperature CCT1 of at maximum 10000 K, such as at maximum 8000 K, especially at maximum 6000 K and the first correlated color temperature CCT1 may be at least 2500 K, such as at least 4000 K, especially at least 6000 K.

[0059] In further embodiments, both the first module light and the second module light may comprise white light. In such embodiments, the second module light may be white light having a second correlated color temperature CCT2 of at maximum 10000 K, such as at maximum 8000 K, especially at maximum 6000 K, especially wherein the first module light is white light having a first correlated color temperature CCT1 of at least 1800 K, such as at least 2500 K, especially at least 3500 K. In further embodiments, the first correlated color temperature CCT1 may be at most 7000 K, such as at most 5000 K, especially at most 3000 K. In particular, in these embodiments wherein both the first module light and the second module light are white light, then CCT2-CCT1 > 300 K, such as > 500 K, especially > 750 K. Such embodiments may provide a distinct look to the first module light and the second module light, even when both are white light. For instance, such embodiments could facilitate providing the illusion of a grey sky on a rainy day.

[0060] Besides natural variation in weather type (e.g., sunny vs. rainy weather), there are also spatial and temporal fluctuations in the sky. Further, if a room, e.g., an office room, contains a (non-artificial) skylight there are often other structures, such as trees and buildings, visible in the surrounding area. Hence, the illusion may be further strengthened by facilitating lighting variations and / or by providing light such that an illusion of a structure is provided.

[0061] Hence, in embodiments, the one or more light generating devices may be configured such that in the first operational mode one or more of the following applies: (a) the second part of the device light has a spatial or temporal variation in one or more of spectral power and radiant flux, or (b) an object is configured intercepting part of the second part of the device light propagating to the second light escape area.

[0062] In further embodiments, the one or more light generating devices may be configured such that in the first operational mode the second part of the device light has a spatial or temporal variation in one or more of spectral power distribution and radiant flux, especially at least a spatial variation in the spectral power distribution, or especially at least a temporal variation in spectral power distribution, especially at least a spatial variation in radiant flux, or especially at least a temporal variation in radiant flux.

[0063] The term “radiant flux” may especially refer to the radiant energy emitted per unit time (by the one or more light generating devices). Instead of the term “radiant flux”, also the terms “intensity” or “radiant power” may be applied. The term “radiant flux” may have as unit an energy, like especially Watts. The term “spectral power distribution” with respect to device light may herein refer to the energy intensity of the device light as a function of wavelength. Hence, a “spectral power distribution variation” in device light may refer to a change in the wavelength-dependent intensity distribution of the device light.

[0064] For instance, by temporally and spatially varying the radiant flux and / or spectral power distribution, the lighting module may provide a sunset and / or sunrise light experience.

[0065] In further embodiments, the one or more light generating devices may be configured such that in the first operational mode an object is configured intercepting part of the second part of the device light propagating to the second light escape area. For instance, a scenery object, such as a (translucent) image of a tree or a church, may be arranged downstream of the second light escape area (from the third light escape area). In embodiments, the object may be (essentially) static. In further embodiments, the object may move and / or change shape (over time), especially move, or especially change shape, such as both move and shape, e.g., in the context of a cloud moving along the second light escape area while changing shape.

[0066] It will be clear to the person skilled in the art that many variations are possible in terms of spatial and temporal variations, as well as in terms of different (scenery) objects, without deviating from the concept of the invention. For instance, in embodiments one or more light generating devices may be configured such that in the first operational mode one or more of the following applies (for the second part of the device light as received at the second light escape area): (a) a spectral power distribution of the second part of the device light varies over time, (b) a spectral power distribution of the second part of the device light varies over the second light escape area, (c) a radiant flux of the second part of the device light varies over time, (d) a radiant flux of the second part of the device light varies over the second light escape area, (e) a stationary object is configured intercepting part of the second part of the device light propagating to the second light escape area, (f) a moving object is configured intercepting part of the second part of the device light propagating to the second light escape area, and (g) a shape changing object, changing its shape with time, is configured intercepting part of the second part of the device light propagating to the second light escape area.

[0067] For instance, in embodiments, the light generating system, especially the control system, may be configured to temporally and / or spatially vary the radiant flux or the spectral power distribution of the device light, especially of the second part of the device light. In further embodiments, the light generating system, especially the control system, may be configured to provide temporal variations in the device light by moving (at least part of) the one or more light generating devices. Hence, in embodiments, (at least part of) the one or more light generating device may be movable.

[0068] For instance, in embodiments, the one or more light generating devices may comprise a moving projection device configured to generate a beam of projection device light. In further embodiments, the one or more light generating devices may (further) comprise a stationary projection device configured to generate a beam of projection device light. In particular, the (moving / stationary) projection device may be configured to project an image onto or behind the second light escape area. Especially, a projection device or “projector” or “image projector” may be an optical device that projects an image (or moving images) onto a surface, such as e.g. a projection screen, or such as interior surface of the enclosure (see above).

[0069] For instance, in embodiments wherein the one or more light generating devices comprise a projection device, the projection device may especially be configured to irradiate an enclosure window comprised by the first light escape area. Hence, in embodiments, the first light generating device (see above) may comprise the projection device.

[0070] Similarly, in embodiments wherein the one or more light generating devices comprise a projection device, the projection device may especially be configured to irradiate a light transmissive element comprised by the second light escape area. Hence, in embodiments, the second light generating device (see above) may comprise the projection device.

[0071] In further embodiments wherein the one or more light generating devices comprise a projection device, the projection device may be configured to irradiate a light reflective wall comprised by the enclosure (see above). In further embodiments, the one or more light generating devices may be configured such that in the first operational mode the second part of the device light received at the second light escape area at least temporarily displays one or more objects selected from a scenery, a horizon, a building, and a cloud, especially at least a scenery, or especially at least a horizon, or especially at least a building, or especially at least a church. The term “scenery” may herein especially refer to features of a landscape, e.g., a hill and / or a waterfall.

[0072] The illusion of a roof window may further be strengthened by providing a visual appearance of the frame of a roof window, either by providing an essentially 2D structure, such as a drawing or a picture, or by providing a (3D) frame (or “beam structure”).

[0073] In embodiments, the light generating system may comprise a 2D structure resembling a window frame, especially wherein the 2D structure is arranged at one or more of (a) an interface between the first and second light escape area, or (b) an interface between two second light escape areas.

[0074] In further embodiments, the light generating system may comprise a frame (or “beam structure”) resembling a roof window. Hence, in embodiments, the light generating system may comprise a frame comprising a plurality of (solid) beams. In particular, in embodiments, the frame may comprise a plurality of first beams defining the first light escape area. For instance, the plurality of first beams may define a rectangular shape, especially a square shape. In further embodiments, the frame may further comprise a plurality of second beams (or “roof supporting pillars”), especially wherein the second beams are arranged perpendicularly to the first beams, and especially wherein the second beams define at least part of the second light escape area. In particular, in such embodiments, the lighting module may comprise a plurality of second light escape areas, wherein neighboring second light escape areas are separated by a (respective) second beam. For instance, in such embodiments, the second beams may be arranged at (and mechanically connected to) corners of the rectangular shape of first beams. In further embodiments, the frame may comprise (only) second beams, wherein the second beams are arranged to bridge at least part of the distance between the first light escape area and the third light escape area. In such embodiments, the second beams may be opaque and configured to support a light emitting surface or light transmissive window of the first light generating device (see above) or a white diffuse element (see above), especially the light emitting surface, or especially the light transmissive window, or especially the white diffuse element.

[0075] In embodiments, the second beams may comprise a first region and a second region, wherein the first region and the second region differ in (surface) color, especially wherein the color of the first region is a shade of the color of the second region, i.e. the first region is darker than the second region. In further embodiments, at least part of the second beams may comprise a color gradient, especially a shade gradient. The presence of a color difference, especially a shade, on the surface of the second beams may contribute to an illusion of solar direction by resembling a natural shade. In particular, a color gradient difference may contribute to the illusion of solar direction, i.e. sunstruck and shadow portions are suggested in using whiter or darker paints at some portions of the window frames.

[0076] The illusion of solar direction may, alternatively or additionally, be provided by spatially varying the intensity of the device light travelling from the first light escape area. For instance, in embodiments, the light generating devices may be configured to spatially vary the amount of device light received at the first light escape area, especially received at a light transmissive window or at a white diffuse element. Such embodiments may further facilitate temporally varying the amount of device light, which may provide a visual experience simulating the Earth’s rotation relative to the sun. In further embodiments, a layer having spatially varying optical properties, e.g., a thin and transparent sheet of plastic, may be arranged on a surface of the light transmissive window or of the white diffuse element, especially on a surface facing the third light escape area. Especially, a (constant) outline, especially matching the second beams (see above) may be provided. Thereby, a spatially varying flux may enhance the experience of solar position by providing the illusion of shade being cast by a second beam.

[0077] In a cross-sectional plane parallel to the ceiling, skylights may typically have a rectangular shape. Hence, in embodiments, in a cross-sectional plane parallel to the ceiling, the lighting module, especially the third light escape area, may have a rectangular shape. By extent, in embodiments, in a cross-sectional plane parallel to the ceiling, the frame may have a rectangular shape. However, other shapes are not excluded. For instance, in a cross- sectional plane parallel to the ceiling, rather than a rectangular (or square) lighting module, the lighting module may be rounded, such as circular, or have any other shape, such as a hexagonal shape for example. Similarly, where in a rectangular arrangement the lighting module may comprise four (sections of a) second light escape area(s), the lighting module may comprise, for example, three or six (sections of a) second light escape area(s) in a triangular or hexagonal configuration. Hence, rather than a default four “windows”, the lighting module of the invention may comprise one, two, three or more second light escape areas (resembling windows). The second light escape areas may be of equal size, but may also vary in size. In embodiments wherein the lighting module comprises a plurality of second light escape areas, the lighting module may be configured to independently control the generation of light for each of the second light escape areas. In particular, the lighting module may be configured such that at least two of the second light escape areas differ in a displayed object, e.g., in scenery.

[0078] In embodiments, the first light escape area may have a plate-like or planar shape. Hence, in embodiments, the first light escape area may have a “flat” shape. In general, in embodiments, the first light escape area may be arranged essentially parallel to the (suspended) ceiling. However, in specific embodiments, the first light escape area may be arranged at an angle to the (suspended) ceiling. Thereby, the illusion of a tilted roof may be provided.

[0079] In further embodiments, the first light escape area may have a curved or wavy shape, e.g., due to a light transmissive window or a white diffuse element having a curved or wavy surface, which may enrich the light scene experience.

[0080] In a further aspect, the invention may provide an indoor space (or “space”) comprising the light generating system of the invention. The space may in embodiments comprise one or more of a wall, a slanted wall, a room divider, a roof, a slanted roof and a ceiling. Especially the indoor space may further comprise the light generating system functionally coupled to the ceiling, such as suspended from the roof, the slanted roof, or the ceiling. In other embodiments, the light generating system may be physically attached to the ceiling, such as by means of screws or fasteners. Hence, in this way, the light generating system may be functionally coupled to the ceiling. Further, in embodiments, the light generating system may be configured to illuminate the indoor space with system light, especially with first lighting module light and second lighting module light. In particular, the indoor space may comprise a ceiling, especially a suspended ceiling, wherein the lighting module is functionally coupled to the ceiling. In embodiments, the (suspended) ceiling may comprise a recess, wherein the lighting module is arranged in the recess.

[0081] The term “indoor space” or “space” may for instance relate to a (part of) hospitality 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 theatre, a library, etc. The term “space” may also relate to (a part of) a working space, such as an office, a (production) plant, a power plant (like a nuclear power plant, a gas power plant, a coal power plant, etc.), etc. For instance, the term “space” may also relate to a control room, a security room, etc.. Especially, the term “space” may herein refer to an indoor space. In yet other embodiments, the term “space” may also relate to a toilet room or bathroom. In embodiments, the term “space” may also refer to a conference room, a school room, an indoor hallway, an indoor corridor, an indoor space in an elderly home, an indoor space in a nursing home, etc. In embodiments, the term “space” may refer to an indoor sport space, like a gym, a gymnastics hall, in indoor ball sport space, a ballet room, a swimming pool, a changing room, etc. In embodiments, the term “space” may refer to an (indoor) bar, an (indoor) disco, etc.

[0082] In embodiments, the indoor space, especially the light generating system, may comprise a control system, wherein the control system is configured to control the light generating system, especially the lighting module, in dependence of one or more of an input signal of a user interface, a sensor signal of a sensor, and a timer.

[0083] In particular, in embodiments, the indoor space may comprise a sensor, wherein the sensor is configured to (i) detect the presence and / or movement of a human in the indoor space and (ii) provide a related sensor signal to the control system, wherein the control system is configured to control the light generating system, especially the lighting module, in dependence of the sensor signal.

[0084] In further embodiments, the control system may be configured to control the light generating system, especially the lighting module, in dependence of a local weather condition at the indoor space, i.e., at the geographical location where the indoor space is located. In further embodiments, , the control system may be configured to control the light generating system, especially the lighting module, in dependence of an online signal, i.e., the control system may be configured to receive and / or obtain data from an online resource, and may be configured to control the light generating system based on the data.

[0085] The terms “upstream” and “downstream” relate to an arrangement of items or features relative to the propagation of the light from a light generating means (here the especially the light source), wherein relative to a first position within a beam of light from the light generating means, a second position in the beam of light closer to the light generating means is “upstream”, and a third position within the beam of light further away from the light generating means is “downstream”. 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. Herein, UV may especially refer to a wavelength selected from the range of 190-380 nm, such as 200-380 nm. The light generating system may be part of or may be applied in e.g. office lighting systems, household application systems, shop lighting systems, home lighting systems, and disinfection systems.

[0086] The control system may also be configured to receive and execute instructions from a remote control. In embodiments, the control system may be controlled via an App on a device, such as a portable device, like a Smartphone or I-phone, a tablet, etc.. The device is thus not necessarily coupled to the lighting system, but may be (temporarily) functionally coupled to the lighting system. Hence, in embodiments the control system may (also) be configured to be controlled by an App on a remote device.

[0087] Instead of the terms “lighting device” or “lighting system”, and similar terms, also the terms “light generating device” or “light generating system”, (and similar terms), may 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”). The lighting device may comprise a light source. The device light may in embodiments comprise one or more of light source light and converted light source light (such as luminescent material light).

[0088] The light generating system may especially comprise one or more solid state light sources. The light generated in the light generating system described herein may especially be generated by these solid state light sources. Hence, the system light may comprise light of one or more solid state light sources, such as LEDs.

[0089] BRIEF DESCRIPTION OF THE DRAWINGS

[0090] Embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, and in which:

[0091] Fig. 1 A-E schematically depict embodiments of the light generating system;

[0092] Fig. 2A-B schematically depict further embodiments of the light escape areas of the light generating system;

[0093] Fig. 3 schematically depicts embodiments of the second light escape area of the light generating system;

[0094] Fig. 4 schematically depicts an embodiment of an indoor space.

[0095] The schematic drawings are not necessarily to scale.

[0096] DETAILED DESCRIPTION OF THE EMBODIMENTS Fig. 1 A schematically depicts an embodiment of the light generating system 1000 comprising a lighting module 1500. In the depicted embodiment, the lighting module 1500 comprises a skylight module. Further, the depicted lighting module 1500 comprises one or more light generating devices 100, a first light escape area 1510, a second light escape area 1520, and a third (light transparent) light escape area 1530. As visualized by the arrows, the one or more light generating devices 100 are configured to generate device light 101, particularly towards the second light escape area. In the depicted embodiment, the first light escape area 1510 and the second light escape area 1520 are configured under a mutual angle (a) selected from the range of 30-150°; specifically a may be (about) 90° in the depicted embodiment. Further, a first distance dl between the first light escape area 1510 and the third light escape area 1530 may be at least partly bridged by the second light escape area 1520. The light generating system 1000 further comprises a system end window 1010, wherein the system end window 1010 comprises the third light escape area 1530.

[0097] References 1512, 1522 and 1532 refer to first, second and third light escape windows of the first, second and third light escape areas 1510, 1520, 1530, respectively. The light escape windows may, in embodiments, comprise a solid material, especially a solid translucent material. In further embodiments, the light escape windows may effectively be open spaces, i.e., they may comprise air.

[0098] Fig. 1 A further schematically depicts a first operational mode of the light generating system. Specifically, the depicted light generating system 1000 is configured such that in the first operational mode the light generating system 1000 provides first module light 1511 and second module light 1512, wherein the first module light 1511 comprises a first part of the device light 101 that propagates from the first light escape area 1510 and through the third light escape area 1530, and wherein the second module light 1521 comprises a second part of the device light 101 that propagates from the second light escape area 1520 and through the third light escape area 1530. In further embodiments, the first module light 1511 and the second module light 1521 may differ in one or more of (i) color point and homogeneity of the light 1511,1522 over the respective light escape area 1510,1520.

[0099] In the depicted embodiment, the light generating system 1000, especially the lighting module 1500, further comprises an enclosure 1400, wherein the enclosure 1400 comprises an enclosure window 1430. In particular, the enclosure window 1430 may comprise (or “define”) the third light escape area 1530. The third light escape area 1530 may especially be arranged on a face of the enclosure window 1430 facing away from the first light escape area 1510. Especially, the enclosure window 1430 may comprise the third light escape window 1532.

[0100] In the depicted embodiment, part of the device light 101 may pass through the second light escape area 1520, subsequently be reflected by a white diffuse element 1515 comprising the first light escape area 1510, and, from there, travelling through the enclosure window 1430 comprising the third light escape area 1530 as first module light 1511. Specifically, in the depicted embodiment, the lighting module 1500 comprises a white diffuse element 1515 which is reflective for white light; wherein the white diffuse element 1515 is configured to reflect at least part of the white light of the device light 101. In such embodiments, the white diffuse element 1515 may especially comprise (or “define”) the first light escape area 1510.

[0101] Similarly, part of the device light 101 may pass through the second light escape area 1520 and be reflected or scattered (directly) towards the enclosure window 1430 comprising the third light escape area 1530 as second module light 1521. For instance, in embodiments, the device light 101 may comprise blue light, and the second light escape area 1520 may be defined by a light transmissive window comprising a Rayleigh scatterer for blue light, i.e., blue light may be selectively scattered at the light transmissive window. In such embodiments, the light transmissive window may comprise (or “define”) the second light escape area 1520.

[0102] Hence, in embodiments, the first module light 1511 may be white light, whereas the second module light 1521 may be blue light, wherein the first module light 1511 may be white light having a first correlated color temperature CCT1 of at maximum 10000 K, such as at maximum 8000 K, especially at maximum 6000 K. In further embodiments, the second module light 1521 may (also) be white light, especially white light having a second correlated color temperature CCT2 of at least 1500 K, such as at least 1800 K, especially at least 2500 K, yet wherein CCT2-CCT1 > 300 K, such as > 500 K, especially > 750 K.

[0103] In the depicted embodiment, the light generating system 1000 further comprises a control system 300. The control system 300 may especially be configured to control the lighting module 1500, especially to (individually) control the one or more light generating devices 100, such as in dependence of one or more of an input signal of a user interface 301, a sensor signal of a sensor 310, and a timer (also see Fig. 4). For instance, in embodiments, the light generating system 1000 may further comprise a sensor 310, wherein the sensor 310 is configured (i) to sense presence and / or movement of a human, and (ii) to provide a related sensor signal to the control system, wherein the control system 300 is configured to control the lighting module 1500, especially the one or more light generating devices 100, in dependence of the sensor signal.

[0104] Fig. IB schematically depicts a further embodiment of the light generating system 1000 wherein the one or more light generating devices comprise a first light generating device 110 and a second light generating device 120. The first light generating device 110 may be configured to provide first device light 111, which may especially comprise white light. Similarly, the second light generating device 120 may be configured to provide second device light 121, which may especially comprise blue light, or which may especially comprise white light (having a lower CCT than the first device light 111). Specifically, the first module light 1511 may comprise at least part of first device light 111 generated by the first light generating device 110 and, similarly, the second module light 1521 may comprise at least part of the second device light 121 generated by the second light generating device 120.

[0105] In the depicted embodiment, the lighting module 1500 comprises a white diffuse element 1515 which is transmissive for white light, especially translucent for white light. The white diffuse element 1515 may be configured to transmit at least part of the white light of the device light 101, and, in further embodiments, may comprise (or “define”) the first light escape area 1510.

[0106] Hence, in the depicted embodiment, a first light generating device 110 may provide first device light 111, wherein in a first operational mode (of the light generating system 1000) at least a first part of which may propagate from the first light escape area 1510 through the third light scape area 1510 as first module light 1511. Similarly, the second light generating device may provide second device light 121, wherein in a first operational mode (of the light generating system 1000) at least part of which may propagate from the second light escape area 1520 through the third light escape area 1530 as second module light 1521.

[0107] Fig. IB further schematically depicts an embodiment wherein the first light generating device 110 comprises a light transmissive window 115 comprising a light transmissive material, wherein the light transmissive window 115 comprises (or “defines”) the first light escape area 1510.

[0108] Fig. 1C schematically depicts a further embodiment of the light generating system 1000. In the depicted embodiment, the enclosure 1400 has an enclosure shape approximating a dome. Specifically, the one or more light generating devices 100 may be arranged at a base of the ‘dome’ and may be configured to illuminate a light reflective wall 1405, especially a light reflective wall 1405 of a dome roof. Thereby, images may be projected on the roof of the dome, which may be seen through the third light escape area 1530, while the light generating devices 100 may be kept out of view.

[0109] Hence, in embodiments, the enclosure 1400 may have a dome-like shape having a dome roof, especially wherein (at least part of) the one or more light generating devices are configured to illuminate the dome roof.

[0110] In the depicted embodiment, the enclosure window 1430 may especially be an opening in the enclosure 1400.

[0111] Fig. 1C further schematically depicts a lighting device 1500 wherein the third light escape area 1530 comprises air. In such embodiments, the third light escape area 1530 may be arranged parallel to (a surface of ) the ceiling 1310, wherein the lighting device 1500 is arranged recessed into the ceiling 1310.

[0112] Fig. ID schematically depicts a further embodiment of the light generating system 1000. Similarly to Fig. 1C, the enclosure of the embodiment of Fig. ID has a domelike shape. However, in the embodiment of Fig. ID, the one or more light generating devices 100 comprise (i) a first light generating device 110 arranged within a roof element and defining the first light escape area 1510 and (ii) a second light generating device 120 arranged on opposite side of the roof element as the first light generating device 110 and configured to provide second device light 121 to a light reflective wall 1405, especially a light reflective wall 1405 of a dome roof. Thereby, the second light generating device 120 may project images on the light reflective wall 1405 while being obstructed from view.

[0113] In the depicted embodiment, the one or more light generating devices 100, especially the second light generating device 120, comprise(s) a projection device 190 configured to generate a beam of projection device light 191. The projection device 190 may be configured to irradiate the light reflective wall 1405 comprised by the enclosure 1400, especially thereby projecting an image on the light reflective wall 1405. The projection device 190 may, in embodiments, be moving, especially configured movable by the control system 300, thereby facilitating providing a changing image, such as for providing the illusion of a moving cloud.

[0114] In further embodiments, the projection device 190 may be configured to irradiate a light transmissive element (i) comprised by the second light escape area 1520 or (ii) defining the second light escape area 1520.

[0115] In yet further embodiments, a first light generating device 110 may (also) comprise a projection device 190. Fig. IE schematically depicts an embodiment of the light generating system 100, wherein the lighting module 1500 comprises a plurality of second light escape areas 1520 separated by beams 1610, especially by second beams 1612.

[0116] In particular, in the depicted embodiment, the light generating system 1000 comprises a frame 1600 comprising a plurality of second beams 1610,1612. The second beams 1610, 1612 are arranged to bridge at least part of the distance dl between the first light escape area 1510 and the third light escape area 1530. In the depicted embodiment, the third light escape area 1530 is arranged parallel to the ceiling 1310 and comprises air, whereas the first light escape area 1510 is comprised by (or “defined by”) a white diffuse element 1515. The second beams 1610,1612 are further arranged to define at least part of the second light escape areas 1520, especially wherein neighboring second light escape areas 1520 are separated by a respective second beam 1610, 1612. In embodiments, the second beams 1610, 1612 may be opaque and configured to support a light emitting surface or light transmissive window of the first light generating device 110 or a white diffuse element 1515.

[0117] As visually apparent in Fig. IE, the presence of the frame 1600, especially the beams 1610, may enhance the skylight illusion. In the depicted embodiment, the lighting module 1500 is further configured such that in the first operational mode the second part of the device light received at (at least one of) the second light escape area(s) displays a cloud.

[0118] Fig. 2A schematically depicts bottom perspective views of two embodiments of the light generating system 1000, wherein the light generating system 1000 is arranged in a ceiling 1310, especially arranged recessed in the ceiling 1310. The hashed area schematically indicates the second light escape area 1520, whereas the enclosed rectangular area schematically indicates the first light escape area 1510. In the bottom view, both the first and the second light escape areas 1510, 1520 are seen through the third light escape area 1530.

[0119] In embodiment (II), the lighting device 1500 further comprises a fourth light escape area 1540. In such embodiments, the light generating system 1000, especially the lighting device 1500, may be configured to further provide fourth module light. Especially, in the first operational mode, the light generating 1000 system may provide fourth module light, wherein the fourth module light propagates from the fourth light escape area 1540. The fourth light escape area may, in a bottom view, at least partially surround the third light escape area 1530, such as in the depicted embodiment wherein the fourth light escape area 1540 (fully) surrounds the third light escape area 1530. In further embodiments, the fourth light escape area 1540 may be arranged in-plane with the third light escape area 1530. In the depicted embodiments, the third light escape area 1530 has a rectangular shape. In further embodiments, the third light escape area may also have different shapes, such as a (different) polygonal shape with 3-8 sides, especially having 3, 4 or 6 sides, or such as a rounded shape, such as a circular shape.

[0120] Fig. 2B schematically depicts embodiments of the lighting module 1500, specifically of the arrangement of the first, second and third light escape areas 1510, 1520, 1530. In embodiments (I) and (III), the second light escape area comprises a solid element, such as a light transmissive window, whereas in embodiment (II), the second light escape area comprises an opening, i.e., the second light escape area 1520 may essentially comprise air. Similarly, in embodiment (III), the third light escape area 1530 comprises a solid element, such as a (solid and transparent) system end window 1010, whereas in embodiments (I) and (II), the third light escape area comprises an opening, i.e., the third light escape area may essentially comprise air.

[0121] Fig. 3 schematically depicts three embodiments of the second light escape area 1520 wherein the second part of the device light 101 has a spatial variation in one or more of spectral power distribution and radiant flux. Specifically, embodiments (I), (II) and (III) schematically depict clouds, a scenery comprising mountains, and buildings, respectively. The images on the second light escape area may especially be provided by projecting the images on a surface (see above) or by arranging an object (or “obstruction”) to intercept part of the device light 101 propagating to the second light escape area 1520.

[0122] Hence, in embodiments, the one or more light generating devices 100 may be configured such that in the first operational mode an object is configured intercepting part of the second part of the device light 101 propagating to the second light escape area 1520. Especially, the one or more light generating devices 100 may be configured such that in the first operational mode the second part of the device light 101 received at the second light escape area 1520 at least temporarily displays one or more objects selected from a scenery, a horizon, a building, and a cloud.

[0123] Additionally or alternatively, in embodiments, the second part of the device light 101 may have a temporal variation in one or more of spectral power distribution and radiant flux. The temporal variation may, for instance, be provided by varying the spectral power distribution of the one or more light generating devices, but may further be provided by moving light sources and / or objects (or “obstructions”).

[0124] Hence, the light generating system 1000, especially the lighting module 1500, may be configured to provide second device light 121 having a spatial and / or temporal variation. For instance, in embodiments, the one or more light generating devices 100 may be configured such that in the first operational mode one or more of the following applies (for the second part of the device light 101 as received at the second light escape area 1520): (a) a spectral power distribution of the second part of the device light 101 varies over time, (b) a spectral power distribution of the second part of the device light 101 varies over the second light escape area 1520, (c) a radiant flux of the second part of the device light 101 varies over time, (d) a radiant flux of the second part of the device light 101 varies over the second light escape area 1520, (e) a stationary object is configured intercepting part of the second part of the device light 101 propagating to the second light escape area 1520, (f) a moving object (especially moving with time) is configured intercepting part of the second part of the device light 101 propagating to the second light escape area 1520, and (g) a shape changing object, changing its shape with time, is configured intercepting part of the second part of the device light 101 propagating to the second light escape area 1520.

[0125] Fig. 4 schematically depicts an embodiment of an indoor space 1300. In the depicted embodiment, the indoor space 1300 comprises a ceiling 1310 and the light generating system 1000, wherein the lighting module 1500 (of the light generating system 1000) is functionally coupled to the ceiling 1310. Especially, in the depicted embodiment, the lighting module 1500 is recessed into the ceiling 1310. In further embodiments, the ceiling 1310 may comprise a suspended ceiling.

[0126] In the depicted embodiment, the indoor space 1300 further comprises a control system 300, wherein the control system 300 is configured to control the lighting module 1500, especially in dependence of one or more of an input signal of a user interface, a sensor signal of a sensor 310, and a timer. Especially, in further embodiments, a sensor may be configured to detect presence and / or movement of a human in the indoor space and to provide a related sensor signal to the control system 300, wherein the control system is configured to control the lighting module 1500 based on the sensor signal. Specifically, the control system 300 may switch the light generating devices 100 on or off depending on the presence or (prolonged) absence of a human in the indoor space, respectively.

[0127] Reference 301 indicates a user interface which may be functionally coupled with the control system 300 comprised by or functionally coupled to the light generating system 1000. References 1305, 1307 and 1310 indicate the floor, wall and ceiling of the indoor space 1300, respectively.

[0128] The term “plurality” refers to two or more. The terms “substantially” or “essentially” herein, and similar terms, will be understood by the person skilled in the art. The terms “substantially” or “essentially” may also include embodiments with “entirely”, “completely”, “all”, etc. Hence, in embodiments the adjective substantially or essentially may also be removed. Where applicable, the term “substantially” or the term “essentially” may also relate to 90% or higher, such as 95% or higher, especially 99% or higher, even more especially 99.5% or higher, including 100%. The term “comprise” also includes embodiments wherein the term “comprises” means “consists of’. The term “and / or” especially relates to one or more of the items mentioned before and after “and / or”. For instance, a phrase “item 1 and / or item 2” and similar phrases may relate to one or more of item 1 and item 2. The term "comprising" may in an embodiment refer to "consisting of but may in another embodiment also refer to "containing at least the defined species and optionally one or more other species". Use of the verb "to comprise" and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise”, “comprising”, and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”. The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

[0129] Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

[0130] The devices, apparatus, or systems may herein amongst others be described during operation. As will be clear to the person skilled in the art, the invention is not limited to methods of operation, or devices, apparatus, or systems in operation.

[0131] 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.

[0132] The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In a device claim, or an apparatus claim, or a system claim, enumerating several means, several of these means may be embodied by one and the same item of hardware. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. In yet a further aspect, the invention (thus) provides a software product, which, when running on a computer is capable of bringing about (one or more embodiments of) the method as described herein. The invention also provides a control system that may control the device, apparatus, or system, or that may execute the herein described method or process. Yet further, the invention also provides a computer program product, when running on a computer which is functionally coupled to or comprised by the device, apparatus, or system, controls one or more controllable elements of such device, apparatus, or system. The invention further applies to a device, apparatus, or system comprising one or more of the characterizing features described in the description and / or shown in the attached drawings. The invention further pertains to a method or process comprising one or more of the characterizing features described in the description and / or shown in the attached drawings. The various aspects discussed in this patent can be combined in order to provide additional advantages. Further, the person skilled in the art will understand that embodiments can be combined, and that also more than two embodiments can be combined. Furthermore, some of the features can form the basis for one or more divisional applications.

Claims

CLAIMS:

1. A light generating system (1000) comprising a lighting module (1500), wherein the lighting module (1500) comprises a skylight module; wherein the lighting module (1500) comprises one or more light generating devices (100), a first light escape area (1510), a second light escape area (1520), and a third light escape area (1530); wherein: the one or more light generating devices (100) are configured to generate device light (101); the first light escape area (1510) and the second light escape area (1520) are configured under a mutual angle (a) selected from the range of 30-150°; wherein a first distance (dl) between the first light escape area (1510) and the third light escape area (1530) is at least partly bridged by the second light escape area (1520); wherein the light generating system (1000) comprises a system end window (1010), wherein the system end window (1010) comprises the third light escape area (1530); and the light generating system (1000) is configured such that, when coupled to a ceiling or a recessed ceiling, in a first operational mode the light generating system (1000) to provide in a vertical direction first module light (1511) representing sunlight and to provide in a horizontal direction second module light (1521) representing skylight, wherein the first module light (1511) comprises a first part of the device light (101) that propagates from the first light escape area (1510) and through the third light escape area (1530), and wherein the second module light (1521) comprises a second part of the device light (101) that propagates through and from the second light escape area (1520) and through the third light escape area (1530); wherein the first module light (1511) and the second module light (1521) differ in one or more of (i) color point and (ii) homogeneity of the light (1511,1522) over the respective light escape area (1510,1520), and wherein first module light (1511) has a first correlated color temperature CCT1 in a range of 1800 - 6000 K, and the second module light (1521) is blue light or has a second correlated color temperature CCT2 in a range of 6500 - 20000 K.

2. The light generating system (1000) according to claim 1, wherein the lighting module (1500) comprises an enclosure (1400), wherein the enclosure (1400) comprises an enclosure window (1430), wherein the enclosure window (1430) comprises the third light escape area (1530).

3. The light generating system (1000) according to claim 2, wherein the enclosure window (1430) is an opening in the enclosure (1400).

4. The light generating system (1000) according to any one of the preceding claims, wherein the device light (101) comprises blue light, and wherein the second light escape area (1520) is defined by a light transmissive window comprising a Rayleigh scatterer for blue light.

5. The light generating system (1000) according to any one of the preceding claims, wherein the device light (101) comprises white light, wherein the lighting module (1500) comprises a white diffuse element (1515) which is reflective or translucent for white light; wherein the white diffuse element (1515) is configured to reflect or transmit at least part of the white light of the device light (101), and wherein the white diffuse element (1515) comprises the first light escape area (1510).

6. The light generating system (1000) according to any one of the preceding claims, wherein the one or more light generating devices (100) comprise a first light generating device (110) configured to generate white first device light (111); wherein the light generating system (1000) is configured such that in the first operational mode at least part of the first white device light (111) escapes from the first light escape area (1510).

7. The light generating system (1000) according to claim 6, wherein the first light generating device (110) comprises a light transmissive window (115) comprising a light transmissive material, wherein the light transmissive window (115) comprises the first light escape area (1510).

8. The light generating system (1000) according to any one of the preceding claims, wherein the one or more light generating devices (100) comprise a second light generating device (120) configured to generate second device light (121); wherein the lightgenerating system (1000) is configured such that in the first operational mode at least part of the second device light (121) escapes from the second light escape area (1520).

9. The light generating system (1000) according to any one of the preceding claims, wherein the first module light (1511) is white light having a first correlated color temperature CCT1 of at maximum 8000 K, and wherein the second module light (1521) is (i) blue light or (ii) white light having a second correlated color temperature CCT2 of at least 1800 K; wherein when both the first module light (1511) and the second module light (1521) are white light, then CCT2-CCTl>500 K.

10. The light generating system (1000) according to any one of the preceding claims, wherein the one or more light generating devices (100) are configured such that in the first operational mode one or more of the following applies: (a) the second part of the device light (101) has a spatial or temporal variation in one or more of spectral power distribution and radiant flux, or (b) an object is configured intercepting part of the second part of the device light (101) propagating to the second light escape area (1520).

11. The light generating system (1000) according to any one of the preceding claims, wherein the one or more light generating devices (100) comprise projection device (190) configured to generate a beam of projection device light (191), wherein the projection device (190) is configured to irradiate one or more of (a) a light transmissive element (i) comprised by the second light escape area (1520) or (ii) defining the second light escape area (1520), and (b) a light reflective wall (1405) comprised by the enclosure (1400) as defined in claim 2.

12. The light generating system (1000) according to any one of claims 10-11, wherein the one or more light generating devices (100) are configured such that in the first operational mode the second part of the device light (101) received at the second light escape area (1520) at least temporarily displays one or more objects selected from a scenery, a horizon, a building, and a cloud.

13. The light generating system (1000) according to any one of the preceding claims, wherein the lighting module (1500) comprises a plurality of second light escape areas (1520), wherein the light generating system (1000) comprises a frame (1600) comprising aplurality of second beams (1612), wherein the second beams (1612) (i) are arranged to bridge at least part of the distance (dl) between the first light escape area (1510) and the third light escape area (1530), and (ii) define at least part of the second light escape areas (1520).

14. An indoor space (1300) comprising a ceiling (1310) and the light generating system (1000) according to any one of the preceding claims, wherein the lighting module (1500) is functionally coupled to the ceiling (1310).

15. The indoor space (1300) according to claim 14, further comprising a control system (300), wherein the control system (300) is configured to control the lighting module (1500) in dependence of one or more of an input signal of a user interface, a sensor signal of a sensor (310), and a timer.

Images