Cost-effective engineering diffusers for laser-based lighting application

Abstract

The invention provides a light generating system (1000) comprising a first regular array (500) of solid state light sources (10) and an optical element arrangement (2000), wherein: (A) the first regular array (500) is an n*m array, wherein n ≥ 1 and m ≥ n; wherein n + m ≥ 4; wherein the first regular array (500) of solid state light sources (10) has a first pitch (p1) in a first direction; wherein the first regular array (500) of solid state light sources (10) is configured to generate a first beam (5) of light source light (11); (B) the optical element arrangement (2000) is configured in a light receiving relationship with the first regular array (500) of solid state light sources (10); wherein the optical element arrangement (2000) comprises k lens arrangements (400); wherein k ≥ 1; wherein each lens arrangement (400) comprises a plurality of lenses (30) arranged in a second array (600); wherein the plurality of lenses (30) in each lens arrangement (400) have an average center-to- center distance (d1); wherein p1 / d1 ≥ 1.4; and (C) the optical element arrangement (2000) is configured to one or more of (i) diffuse and (ii) shape the first beam (5) of light source light (11) into a second beam (6) of light source light (11).

Description

[0001] 2024PF80145

[0002] 1

[0003] COST-EFFECTIVE ENGINEERING DIFFUSERS FOR LASER-BASED LIGHTING

[0004] APPLICATION

[0005] FIELD OF THE INVENTION

[0006] The invention relates to a light generating system. The invention further relates to a lighting device comprising the light generating system.

[0007] BACKGROUND OF THE INVENTION

[0008] Diffusers are known in the art. For instance, US2021333442A1 describes a micro-optic cell design with a regularly spaced micro-lens array, having a series of randomly positioned lenslets that have been digitally overwritten, wherein the overwritten area is greater than 0 up to 100 percent fill, and wherein a light shaping diffuser pattern is placed on top of the lenslets of the micro-optic cell.

[0009] US2008 / 043466A1 discloses a lighting device for efficiently distributing light over an area to provide uniform illumination over a wide angle or other tailored illumination patterns. Each light device has at least one light source, at least one collimator for partially collimating light from the light source, and at least one diffuser for diffusing light from the collimator. The diffuser provides diffused light over an area from the diffuser having an intensity that is angularly dependent in accordance with the angular distribution intensity of light outputted from the collimator, so as to provide a predetermined illumination pattern from the device. The light sources and collimators may be provided in one or two- dimensional arrays, and a single diffuser may be formed on each collimator or the diffuser may be along a plate spaced from the collimator.

[0010] SUMMARY OF THE INVENTION

[0011] Lighting systems providing circular spots or beams may be desired in various lighting applications, such as in the entertainment industry, in retail lighting, and for search lights. Especially, it may be desired that the provided light is relatively uniform. However, prior art lighting systems may be limited in beam-shaping. For instance, prior art systems, especially narrow beam high flux systems (such as laser-based light sources), may be unsuitable for providing a smooth round beam. For laser-based phosphor converted lighting 2024PF80145

[0012] 2 systems, the light emitting area of the system may be defined by irradiance profile of the pumping laser, and may typically have an elliptical shape with a non-uniform luminance. Such asymmetric and non-uniform sources may make it challenging to create round symmetric beams (using standard optics). For instance, in high-brightness, high-light-output light engines the light from a rectangular array of blue pump lasers may need to be imaged onto a uniform, circular spot on a luminescent material. The laser beams may propagate very well collimated from the package. With a conventional lens they would be focused to a very small, very high irradiance hot spot on the phosphor, resulting in an asymmetric and non- uniform beam, and causing (thermal and / or photo-)degradation of the phosphor. To homogenize the laser beams on the phosphor, a mixing rod or diffusing optics (“diffusers”) might be used. However, prior art diffusers providing a beam with a uniform (and rotational symmetrical) light distribution may be expensive and difficult to engineer. For instance, prior art diffusers may use photolithography techniques with a high spatial resolution. As such, there may be a need for a cost-effective optical solution for providing a uniform beam of light. 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.

[0013] According to a first aspect, the invention provides a light generating system comprising a first regular array of (a plurality ol) solid state light sources and an optical element arrangement. The first regular array may be an n*m array, wherein n > 1 and m > n. In embodiments, n + m > 4. The first regular array of solid state light sources may have a first pitch pi in a first direction. Further, the first regular array of solid state light sources may be configured to generate a first beam of light source light. The optical element arrangement may be configured in a light receiving relationship with the first (regular) array of solid state light sources. Further, the optical element arrangement may comprise k lens arrangements. In embodiments, k > 1. Further, each lens arrangement (of the k lens arrangements) may comprise a plurality of lenses arranged in a second array. The plurality of lenses in each lens arrangement may have an (per lens arrangement individually selected) average center-to- center distance di. In embodiments, pi / di > 1.4. The optical element arrangement may be configured to one or more of (i) diffuse and (ii) shape the first beam of light source light. Especially, the optical element arrangement may be configured to one or more of (i) diffuse and (ii) shape the first beam of light source light into a second beam of light source light. Hence, in specific embodiments, the invention provides a light generating system comprising 2024PF80145

[0014] 3 a first regular array of solid state light sources and an optical element arrangement, wherein: (A) the first regular array is an n*m array, wherein n > 1 and m > n; wherein n + m > 4; wherein the first regular array of solid state light sources has a first pitch pi in a first direction; wherein the first regular array of solid state light sources is configured to generate a first beam of light source light; (B) the optical element arrangement is configured in a light receiving relationship with the first regular array of solid state light sources; wherein the optical element arrangement comprises k lens arrangements; wherein k > 1; wherein each lens arrangement comprises a plurality of lenses arranged in a second array; wherein the plurality of lenses in each lens arrangement have an average center-to-center distance di; wherein pi / di > 1.4; and (C) the optical element arrangement is configured to one or more of (i) diffuse and (ii) shape the first beam of light source light into a second beam of light source light.

[0015] Such a light generating system may provide a second beam of light source light having a uniform intensity distribution (in a cross-section of the second beam). Further, such an optical element arrangement may especially be cost-effective to produce, as only relatively cheap techniques may be required to produce the optical element arrangement. Additionally, such an optical element arrangement may be produced from relatively cheap materials, allowing the production of a thicker and more mechanically stable optical element arrangement (for a similar or lower cost compared to prior art systems). Further yet, prior art diffusers may typically (back)scatter part of the light incident on the diffuser to angles outside of the desired angular range for the lighting system, resulting in a spill light and decreasing the optical efficiency. The optical element arrangement of the present invention may improve optical efficiency by reducing the part of the light scattered by the diffusing element of the light generating system.

[0016] The light generating system may comprise a first regular array of (a plurality of) solid state light sources. The term “array” may refer to a regular array, a random array, a quasi-random array, or a tessellation array (see below). The term “array” may especially refer to a 2D array. Further, the term “regular array” may refer to a 2D array having one or two constant pitches. The term “pitch” may refer to a repetitive (center-to-center) distance between repeated elements in an array comprising translational symmetry (i.e., within the array having the pitch the element may be repeatedly translated by a distance of the pitch). In embodiments, the (repeated) elements in the array may be in physical contact (see also below). Alternatively, the (repeated) elements in the array may be physically separated within the array. As indicated above, the first array of solid state light sources may especially be a 2024PF80145

[0017] 4 first regular array. The first regular array may be an n*m array. Hence, in embodiments, the first regular array may comprise n*m solid state light sources. In embodiments, n (in the first regular array) may be selected from the range of > 1, such as from the range of > 2, especially from the range of > 3. Additionally or alternatively, n may be selected from the range of < 15, such as from the range of < 10, especially from the range of < 5, though larger numbers are herein not excluded. Further, m (in the first regular array) may be selected from the range of > n, such as from the range of > 2, especially from the range of > 4. Additionally or alternatively, m may be selected from the range of < 20, such as from the range of < 15, especially from the range of < 10, though larger numbers are herein not excluded. In embodiments, n + m > 4 may apply, such as n + m > 6, especially n + m > 8.

[0018] The first regular array may have a first pitch pi in a first direction. The first direction may especially be one of the direction of n and the direction of m in the first regular array. Further, the first pitch pi may be selected from the range of > 1 mm, such as from the range of > 1.5 mm, especially from the range of > 2 mm. Additionally or alternatively, the first pitch pi may be selected from the range of < 20 mm, such as from the range of < 15 mm, especially from the range of < 10 mm. Hence, in specific embodiments, pi < 15 mm. Such a first pitch pi may facilitate configuring the plurality of solid state light source close enough together that a second beam of light source light having a uniform intensity distribution may be provided. Further, such a first pitch pi may provide a relatively compact first array. In embodiments, the solid state light sources may be in physical contact in the first regular array. Yet, especially, the solid state light sources may be configured physically separated in the first regular array.

[0019] The first regular array may further have a third pitch ps in a second direction. The second direction (having the third pitch ps) may (in embodiments) be orthogonal to the first direction (having the first pitch pi). In embodiments, the solid state light sources in the first regular array may be arranged according to a square grid, wherein ps = pi. Alternatively, the solid state light sources may be arranged according to a rectangular grid, wherein especially ps > pi. Hence, in embodiments, ps > pi, such as ps > 1.1 *pi, especially ps > 1.5*pi. Additionally or alternatively, in embodiments, ps < 5*pi, such as ps < 4*pi, especially ps < 3*pi. Hence, in specific embodiments, the first regular array may have a third pitch ps in a second direction, wherein ps > pi.

[0020] The solid state light sources (in the first regular array) may comprise, such as especially be, any type of light source known in the art. Examples of suitable solid state light sources are provided below. Yet, especially, the solid state light sources may comprise laser 2024PF80145

[0021] 5 light sources, such as laser diodes. Additionally or alternatively, the solid state light sources may comprise one or more of superluminescent diodes and stacked junction light emitting diodes. Hence, in specific embodiments, the solid state light sources may comprise one or more of laser diodes, superluminescent diodes, and stacked junction light emitting diodes. Such solid state light sources may especially provide high-intensity light with a relatively narrow radiance distribution. Further, such solid state light sources may be relatively energyefficient.

[0022] The first regular array of solid state light sources may be configured to generate a first beam of light source light. The first beam of light source light may comprise, especially consist of, a plurality of sub-beams (of light source light) provided by the (separate) solid state light sources in the first regular array. As indicated above, the solid state light sources may provide high-intensity light with a relatively narrow radiance distribution. Especially, the light source light from each of the solid state light sources may be configured to illuminate an area with a first equivalent circular diameter Di, especially on a first major surface of the optical element arrangement (wherein the first major surface of the optical element arrangement may especially be configured facing and in a light receiving relationship with the first regular array). The equivalent circular diameter (or ECD) of an (irregularly shaped) two-dimensional shape is the diameter of a circle of equivalent area. For instance, the equivalent circular diameter of a square with side a is 2a / SQRT(a). For a circle, the diameter D is the same as the equivalent circular diameter D. Would a circle in an xy- plane with a diameter D be distorted to any other shape (in the xy-plane), without changing the area size, then the equivalent circular diameter of that shape would be D. The first equivalent circular diameter Di may be defined by a full width at half maximum (FWHM) of an irradiance distribution of the (sub-beam ol) light source light on the first major surface (of the optical element arrangement). That is, the irradiance may be highest at the center of the illuminated area, and may decrease with increasing distance from the center of the illuminated area, wherein a plurality of points around the center (and within a plane of the first major surface of the optical element arrangement) at which the irradiance drops to 50% of the irradiance at the center of the illuminated area may indicate the boundary defining the half maximum, and wherein a distance between points opposite from each other across the center of the illuminated area may define a FWHM (of the sub-beam). In embodiments, the illuminated area (of a sub-beam) may have a circular shape on the first major surface of the optical element arrangement, wherein the FWHM for every set of (opposite) points may define the first equivalent circular diameter Di. Alternatively, illuminated area (of a sub- 2024PF80145

[0023] 6 beam) may have an elliptical shape on the first major surface of the optical element arrangement, wherein the plurality of points define a FWHM surface area (of said sub-beam), and wherein the FWHM surface area determines the first equivalent circular diameter Di. Especially, for a non-circular illuminated area, a plurality of n (illuminated) area diameters Da may be determined (for each sub-beam) while rotating about the center of the illuminated area (and within a plane of the first major surface of the optical element arrangement), wherein the first equivalent circular diameter Di may be determined by

[0024] (Da,i+Da,2+Da,3+... +Da,n) / n. The first equivalent circular diameter Di (for each sub-beam of light source light) may be (individually) selected from the range of > 0.5 mm, such as from the range of > 1 mm, especially from the range of > 2 mm. Additionally or alternatively, the first equivalent circular diameter Di (for each sub-beam of light source light) may be (individually) selected from the range of < 15 mm, such as from the range of < 10 mm, especially from the range of < 5 mm. In embodiments, the solid state light sources may be configured to generate collimated (sub-beams ol) light source light. Especially, the subbeams of light source light may have a first beam divergence angle 0i of < 2°, such as < 1°, especially < 0.5°, like < 0.3°.

[0025] As indicated above, the plurality of sub-beams (having the first equivalent circular diameter Di in an illuminated area) of the solid state light sources may be comprised by the first beam of light source light. Especially, the first beam of light source light may consist of the plurality of sub-beams. In embodiments, (the irradiance distributions and / or radiant intensity distributions ol) adjacent sub-beams in the first beam may at least partially overlap. Yet, especially, at least 70%, such as at least 80%, especially at least 90%, including (essentially) 100%, of an irradiance and / or radiant intensity (distribution) of a first sub-beam (in the first beam) may not overlap with the irradiance and / or radiant intensity (distribution) of an adjacent sub-beam. Hence, in embodiments, (in the absence of the optical element arrangement) the first beam of light source light may provide distinct “hot spots” upon irradiating an image plane with the first beam (comprising the plurality of sub-beams). The (radiant intensity of the) first beam of light source light may have a FWHM (in the angular domain) in a cross-section perpendicular to the first beam. In embodiments, (in the absence of the optical element arrangement and) within a distance of 120 cm, such as within a distance of 100 cm, especially within a distance of 80 cm, up to a distance of at least 10 cm, from (light emitting surfaces of the solid state light sources in) the first regular array, a radiant intensity of the light source light (in the angular domain, and as seen from a virtual plane parallel to the first regular array) may have a first variance over at least part of a cross- 2024PF80145

[0026] 7 section of the first beam of light source light (wherein the boundaries of the first beam crosssection are defined by the FWHM of the first beam in the angular domain). It will be clear to the person skilled in the art that the distances of within 120 cm, such as within 100 cm, especially within 80 cm, such as up to 10 cm, are arbitrarily chosen to clarify the intensity distribution of the first beam of light source light (as seen from a plane parallel to and downstream from the first regular array). It will further be clear to the skilled person that directly downstream of the first regular array, e.g. within 2 cm from the first regular array, (and in a plane parallel to the first regular array,) the first beam of light source light may consist of individual, spatially separated sub-beams of light source light provided by the individual solid state light sources in the first regular array. The (radiant intensity of the) light source light may have the first variance over at most 85%, such as at most 75%, especially at most 65%, of a cross-section of the first beam of light source light. The at least part of the cross-section having the first variance may be centered in the first beam (i.e., with a first variance over 75% of the cross-section, the outer 12.5% of the cross-section may be disregarded for determining the first variance). Further, the first variance may be determined by normalizing the radiant intensity in said at least part of the cross-section, wherein the highest radiant intensity indicates 100%, a radiant intensity of (essentially) zero indicates 0%, and the difference (in percentage) between the highest and lowest radiant intensity (in said at least part of the cross-section) indicates the first variance. In embodiments, the first variance may be selected from the range of > 20%, such as from the range of > 30%, especially from the range of > 40%. Further, the first variance may be selected from the range of > 60%, such as from the range of > 75%, especially from the range of > 90%, including (essentially) 100%. Hence, in embodiments the radiant intensity of the light source light may reach (essentially) zero in some locations along a (virtual) cross-section of the first beam of light source light (in the angular domain). Yet, in specific embodiments, (pi < 15 mm may apply, wherein) within a distance of 100 cm from the first regular array, a radiant intensity of the light source light may vary > 30% over at most 75% of a cross-section of the first beam of light source light. Such a variance may facilitate that the first regular array may provide a non-uniform beam of light source light. Further, such a variance may facilitate that the subbeams of the solid state light sources may not (fully) overlap (in the angular domain), thereby providing a first beam with a larger (spatial) cross-section (i.e., a larger beam) compared to a first regular array wherein the sub-beams overlap, and a non-uniform irradiance distribution of the first beam of light source light upon irradiating a surface with the first beam. 2024PF80145

[0027] 8

[0028] The light generating system may further comprise the optical element arrangement. The optical element arrangement may be configured in a light receiving relationship with the first regular array of solid state light sources. Hence, the first beam of light source light may be incident on the optical element arrangement. The optical element arrangement may be configured to diffuse (e.g. homogenize) the first beam of light source light (see also below). Especially, the optical element arrangement may be configured to distribute a radiant flux of the (sub-beams ol) light source light over a larger (angular) (cross- sectional) area. That is, a sub-beam of light source light may have a first beam divergence angle Hi upstream of the optical element arrangement, and a second beam divergence angle lh downstream of the optical element arrangement, wherein th > Hi, such as th > 2* Bi, especially th > 4* Hi. 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”. As indicated above, the first beam divergence angle Hi may be selected from the range of < 2°, such as from the range of < 1°, especially from the range of < 0.5°, like from the range of < 0.3°. Further, in embodiments, the second beam divergence angle may be selected from the range of > 2°, such as from the range of > 5°, especially from the range of > 7°, like from the range of > 10°.

[0029] Additionally or alternatively, the second beam divergence angle may be selected from the range of < 25°, such as from the range of < 20°, especially from the range of < 17°, like from the range of < 15°. Hence, downstream of the optical element arrangement, (and in the second beam,) a (spatial) overlap in radiant flux distributions of adjacent sub-beams of light source light may be increased, providing a second beam of light source light having a more uniform radiant flux distribution (over at least part of a cross-section of the second beam of light source light). Especially, a radiant intensity of the light source light may have a second variance over at least part of a cross-section (in the angular domain) of the second beam of light source light (wherein the boundaries of the second beam cross-section are defined by a FWHM of the second beam in the angular domain). The (radiant intensity of the) light source light may especially have the second variance over at least 65%, such as at least 75%, especially at least 85%, of the cross-section (in the angular domain) of the second beam of light source light. The at least part of the cross-section (in the angular domain) having the second variance may be centered in the second beam. Further, the second variance may be 2024PF80145

[0030] 9 determined by normalizing the radiant intensity in said at least part of the cross-section, wherein the highest radiant intensity indicates 100%, a radiant intensity of (essentially) zero indicates 0%, and the difference (in percentage) between the highest and lowest radiant intensity (in said at least part of the cross-section) indicates the second variance. In embodiments, the second variance may be selected from the range of < 20%, such as from the range of < 15%, especially from the range of < 10%, like from the range of < 5%, including (essentially) 0%. That is, a radiant intensity of the light source light downstream of the optical element arrangement may vary < 15% over at least 75% of a cross-section of the second beam of light source light. Hence, in specific embodiments, within a distance of 100 cm from the first regular array of solid state light sources, in the absence of the optical element arrangement, a radiant intensity of the light source light may vary > 30% over at most 75% of a cross-section of the first beam of light source light, and in the presence of the optical element arrangement a radiant intensity of the light source light downstream of the optical element arrangement may vary < 15% over at least 75% of a cross-section of the second beam of light source light. Such an optical element arrangement may thus facilitate diffusing the first beam of light source light into a homogeneous second beam of light source light. Especially, such an optical element arrangement may facilitate providing a second beam of light source light having a (roughly) equal radiant intensity over at least 75% of the cross-section of the second beam.

[0031] Hence, the optical element arrangement may be configured in a light receiving relationship with the first regular array of solid state light sources. Especially, a first major surface of the optical element arrangement may be configured in a light receiving relationship with (and facing) the first regular array. In embodiments, along an optical path of the (first beam ol) light source light, (the first major surface ol) the optical element arrangement may be configured at a distance of > 0.5 mm, such as > 1 mm, especially > 1.5 mm, from (a light emitting surface of the solid state light sources in) the first regular array. Additionally or alternatively, along an optical path of the light source light, (the first major surface ol) the optical element arrangement may be configured at a distance of < 50 cm, such as < 40 cm, especially < 30 cm, from (a light emitting surface of the solid state light sources in) the first regular array. The optical element arrangement may further have a second major surface, configured opposite to the first major surface. The light source light may be emitted from the second major surface as the second beam of light source light. Hence, the second major surface of the optical element arrangement may be configured downstream of the first major surface. The optical element arrangement may comprise a (low absorption) light 2024PF80145

[0032] 10 transmissive material. Herein, the term “light transmissive” material indicates the material may be (specular) transmissive, such as transparent, for one or more wavelengths selected from the range of 190-1500 nm, such as from the range of 200-1000 nm, especially from the range of 380-780 nm (i.e. visible light). Further, the term “low absorption light transmissive” material may indicate that the material may absorb < 10%, such as < 5%, especially < 2%, of a spectral power of (visible) light received by the low absorption light transmissive material (from an angle perpendicular to a face of the low absorption light transmissive material). In embodiments, the light transmissive material may comprise one or more materials selected from the group comprising glass, polycarbonate (PC), polyethylene (PE), polystyrene (PS), polypropylene (PP), polyethylene terephthalate (PET), (clear) polyvinyl chloride (PVC), cyclic olefin copolymers (COC), fluorinated ethylene propylene (FEP), styrene methyl methacrylate (SMMA), polysiloxanes, poly(methyl methacrylate) (PMMA), fused silica, and silicone replica (e.g. on a glass substrate). Especially, the light transmissive material may be selected from the group of glass, fused silica, and silicone replica on a glass substrate. Herein, the term “silicone replica on a glass substrate” may indicate a silicone material (mimicking the optical properties of glass) bound to a glass substrate. For instance, the optical element arrangement may comprise silicone lenses on a glass substrate (e.g. a glass plate). The glass may further be selected from the group comprising N-BK7 glass (SCHOTT, glass code 517-642), H-K51 glass (CDGM, glass code 523-586), H-K9L glass (CDGM, glass code 516-642), and borofloat glass (SCHOTT), though other types of glass are herein not excluded. Hence, in specific embodiments, the optical element arrangement may comprise a light transmissive material selected from the group of NBK7 glass, HK51 glass, HK9L glass, borofloat glass, fused silica, and silicone replica on a glass substrate. Such materials may have a relatively low absorption. Further, such materials may have a suitable refractive index.

[0033] Especially, the (light transmissive material of the) optical arrangement comprises light transparent material. Especially, the optical element arrangement may in embodiments have an absorption length and / or a scatter length of at least 5 times, such as at least 10 times, especially at least 50 times, like at least 100 times, a (largest) thickness of the optical element arrangement. The absorption length may be defined as the length over which the intensity of the light along a propagation direction due to absorption drops with 1 / e. Likewise, the scatter length may be defined as the length along a propagation direction along which light is lost due to scattering and drops thereby with a factor 1 / e. Here, the length may thus especially refer to the distance between a first major surface and a second major surface of the optical element arrangement, with the light transmissive material configured between 2024PF80145

[0034] 11 at least the first major surface and the second major surface. Further, the length may refer to a largest thickness of the optical element arrangement (in a cross-section perpendicular to the first and / or second major surface). The largest thickness may in embodiments especially be the length from the top of the lenses to the furthest of the first major surface and the second major surface (assuming lenses at one side of the optical arrangement; would in embodiments be lenses at both sides of the optical arrangement, then the largest thickness may especially be the length from the tops of the lenses at both sides).

[0035] In embodiments, the optical element arrangement may be configured to transmit > 85%, such as > 90%, especially > 95%, including (essentially) 100%, of a spectral power of the light source light received by the optical element arrangement (from an angle perpendicular to the first major surface of the optical element arrangement). Further, in embodiments, the optical element arrangement may be configured to reflect < 15%, such as < 10%, especially < 5%, including (essentially) 0%, of the spectral power of the light source light received by the optical element arrangement (from an angle perpendicular to the first major surface of the optical element arrangement). In specific embodiments, the optical element arrangement may comprise an antireflection coating. The antireflection coating may be configured on one or more of the first major surface and the second major surface of the optical element arrangement. Further, the antireflection coating may be configured to reduce the amount of light reflected at the first major surface and second major surface. In embodiments, the antireflection coating may be selected from the group comprising a magnesium fluoride (MgF2) coating, a magnesium oxide (MgO) coating, and a multi-layer dielectric stack (comprising e.g. one or more of silicon oxide (SiCh), hafnium oxide (HfCh). and titanium oxide (TiCh).

[0036] The optical element arrangement may comprise k lens arrangements. In embodiments, k may be selected from the range of > 1, such as from the range of > 2, especially from the range of > 3. Additionally or alternatively, k may be selected from the range of < 150, such as from the range of < 100, especially from the range of < 80. Each lens arrangement may comprise a plurality of lenses arranged in a second array. The second array may be a regular array, a random array, a quasi-random array, or a tessellation array. Especially, the second array may be a regular array. In addition to what is described above in relation to the term “regular array”, the term “regular array” may herein further refer to a pattern of (identical) shapes, especially polygons, that fit together closely in a repetitive pattern without gaps or overlapping. Especially, in such embodiments, a set of x adjacent rows (or x adjacent columns) may form a repetitive unit, wherein the repetitive unit may be 2024PF80145

[0037] 12 repeated along the regular array. For instance, the regular array may be formed of hexagons, wherein x = 2, wherein (geometrical centers of) the hexagons of the two rows (or two columns) within the set may be offset with respect to each other (in a direction parallel to the row). In specific embodiments, the regular array may comprise a regular translation array of the entrance shape (e.g. a polygon). The term “regular translation array” may herein especially refer to a regular array wherein the translated shape, such as the polygon, may be moved without rotation or mirroring thereof. Alternatively, the second array may especially be a tessellation array. The term “tessellation” may herein especially refer to a pattern of (different or equal) shapes, especially free-form shapes, that fit together closely without gaps or overlapping. A tessellation array may comprise a non-random pattern, wherein the locations of elements may be precisely mathematically determined. Further, a tessellation array may (essentially) not comprise a repetitive unit. A center-to-center distance between shapes in the tessellation array be individually selected for each set of (adjacent) shapes, i.e., a tessellation array may not have a pitch. Examples of tessellation arrays are provided below. Especially, the second array may be a 2D array.

[0038] As indicated above, each lens arrangement may comprise a plurality of lenses (arranged in a second array). Especially, each lens arrangement may comprise > 6 lenses, such as > 15 lenses, especially > 25 lenses. Further, each lens arrangement may comprise > 40 lenses, such as > 50 lenses, especially > 60 lenses. Additionally or alternatively, each lens arrangement may comprise < 4000 lenses, such as < 3000 lenses, especially < 2000 lenses. The number of lenses in the lens arrangement may be individually selected for each lens arrangement. Yet, especially, each lens arrangement may have the same number of lenses. The plurality of lenses may be configured on the first major surface of the optical element arrangement. Alternatively, the plurality of lenses may be configured on the second major surface of the optical element arrangement. Yet, the plurality of lenses may (also) be configured on (both) the first major surface and second major surface of the optical element arrangement. In such embodiments, the plurality of lenses of the first major surface may be configured aligned with the plurality of lenses on the second major surface. Yet, especially, the plurality of lenses may be configured on the first major surface, wherein the second major surface may be (essentially) planar.

[0039] The plurality of lenses in each lens arrangement may have an average distance di between (geometrical) centers of (directly) adjacent lenses. That is, the plurality of lenses in each lens arrangement may have an average center-to-center distance di. In embodiments, the average center-to-center distance di may be individually selected for each lens 2024PF80145

[0040] 13 arrangement. Hence, each lens arrangement may have the same average center-to-center distance di, or at least two of the lens arrangements (when k > 2) may have a different average center-to-center distance di. The average center-to-center distance di may be selected from the range of > 0.3 mm, such as from the range of > 0.5 mm, especially from the range of > 1 mm. Hence, in specific embodiments, di > 0.5 mm. Lenses having an average center-to- center distance di of > 0.5 mm may facilitate producing the lenses using a relatively cheap method such as glass molding, rather than a relatively expensive method like lithography which would be required for lenses having an average center-to-center distance di of < 0.5 mm. Further, an optical element arrangement wherein di > 0.5 mm may be suitable for use with most regular arrays of solid state light sources known in the art. The average center-to- center distance di may (additionally or alternatively) be selected from the range of < 15 mm, such as from the range of < 10 mm, especially from the range of < 5 mm.

[0041] In embodiments, the average center-to-center distance di may be smaller than the first pitch pi (of the first regular array). Especially, in embodiments, pi / di > 1.2, such as pi / di > 1.4, especially pi / di > 1.8. Further, in embodiments, pi / di > 2.1, such as pi / di > 2.5, especially pi / di > 4. Additionally or alternatively, in embodiments, pi / di < 15, such as pi / di < 10, especially pi / di < 8. In embodiments, 1.2 < pi / di < 15, such as 1.8 < pi / di < 10, especially 2.5 < pi / di < 8. Hence, in specific embodiments, 1.8 < pi / di < 10. Such a ratio between pi and di may facilitate providing a more uniform second beam of light source light downstream of the optical element arrangement. The average center-to-center distance di may further be smaller than four times the first equivalent circular diameter Di. The average center-to-center distance di may be selected from the range of di / Di > 0.1, such as di / Di > 0.2, especially di / Di > 0.3. Additionally or alternatively, the average center-to-center distance di may be selected such that di / Di < 4, such as di / Di < 3, especially di / Di < 2.5. Further, in embodiments, di / Di < 2, such as di / Di < 1.5, especially di / Di < 1. Hence, in specific embodiments, the light source light from each of the solid state light sources may be configured to illuminate an area with a first equivalent circular diameter Di on a first major surface of the optical element arrangement; wherein the first equivalent circular diameter Di may be defined by a full width at half maximum of an irradiance distribution of the light source light on the first major surface; and wherein di / Di < 3. A ratio of di / Di < 3 may facilitate that the area illuminated by a single solid state light source may be smaller than (the surface ol) a lens in the second array. As larger lenses may be easier to produce than small lenses, such a ratio of di / Di may facilitate that the optical element arrangement may be 2024PF80145

[0042] 14 relatively economical to produce. Further, a ration of di / Di < 3 may still be low enough to provide a uniform second beam of light source light.

[0043] The plurality of lenses (in each second array) may be physically coupled. In embodiments, the plurality of lenses (in each second array) may be in (direct) physical contact with each other. Alternatively, the plurality of lenses (in each second array) may be physically coupled via one or more fillets. The term “fillet” is known to the person skilled in the art, and may herein refer to a (rounded) transition between two lenses. The fillet may especially be a concave rounded transition between lenses. That is, would the lenses be configured on the first major surface of the optical element arrangement, a center of the one or more fillets may be configured curving towards the second major surface. Hence, the one or more fillets may physically couple the plurality of lenses, wherein the one or more fillets may be configured between adjacent lenses. Especially, each pair of lenses may be physically coupled by one fillet. Hence, for instance, a first lens physically coupled to six adjacent lenses in the second array may be physically coupled to said six adjacent lenses via six fillets, wherein each fillet may physically couple the first lens to one adjacent lens. In embodiments, the plurality of lenses may thus be physically separated from each other by the one or more fillets. The one or more fillets may have a fillet width Wf. The fillet width Wf may especially be the smallest width of the fillet in between two adjacent lenses. In embodiments, the fillet width Wf may be (for each fillet) individually selected from the range of < 0.15 mm, such as from the range of < 0.1 mm, especially from the range of < 0.05 mm, like from the range of < 0.03 mm. The fillet width Wf may in embodiments be at least partially determined by the production method of the optical element arrangement, wherein the fillet width Wf may essentially always be > 0 mm. Especially, in embodiments, the fillet width Wf may be at minimum 0.005 mm, such as at minimum 0.01 mm, especially at minimum 0.02 mm. Additionally or alternatively, the fillet width Wf may be (for each fillet) individually selected from the range of Wf / di < 0.2, such as from the range of Wf / di < 0.1, especially from the range of Wf / di < 0.05. Hence, in specific embodiments, the lenses may be physically coupled via one or more fillets, wherein the fillets may have fillet widths Wf, and wherein the fillet widths Wf may be individually selected from the range of Wf / di < 0.1. Such a fillet width Wf may be relatively small compared to the center-to-center distance di. Hence, such a fillet width Wf may facilitate that the majority of the light source light incident on the optical element arrangement may be incident on the plurality of lenses (and not on the one or more fillets). 2024PF80145

[0044] 15

[0045] The one or more fillets may define one or more of the first major surface and the second major surface of the optical element arrangement. For instance, the lenses may be configured on the first major surface of the optical element arrangement. In such embodiments, an average distance from the second major surface to (the nearest point on) the one or more fillets (in a direction perpendicular to the second major surface) may determine the location of the first major surface. Alternatively, the lenses may be configured on the second major surface, wherein an average distance from the first major surface to (the nearest point on) the one or more fillets (in a direction perpendicular to the first major surface) may determine the location of the second major surface. Would the lenses be configured on both the first and second major surface, the locations of both the first and second major surface may be determined by an average of the smallest distance between two (opposite) fillets.

[0046] The (plurality ol) lenses may have a radius of curvature Rcin a plane perpendicular to the first (and / or second) major surface of the optical element arrangement. In embodiments, the (plurality ol) lenses may be concave lenses. Yet, especially, the (plurality of) lenses may be convex lenses. In embodiments, the radius of curvature Rcmay be individually selected for each lens arrangement; i.e., in embodiments the lenses in each lens arrangement may have a different radius of curvature Rc. Yet, especially, the lenses in each lens arrangement may have the same radius of curvature Rc. In embodiments, the radius of curvature Rc(in mm) may be determined by Rc= Ro Herein, Ro (with units mm) may indicate the radius of curvature in embodiments wherein the fillet width Wf is zero (Wf = 0), x may be a dimensionless coefficient dependent on the pattern in the second array (i.e., x may be different for e.g. a regular array and a tessellation array), and y may be a constant depending on the (desired) second beam divergence angle th. In embodiments, Ro may be defined as Ro = y*di, wherein y and di are as defined above. In embodiments, y may be selected from the range of > 1.5, such as from the range of > 3, especially from the range of > 4. Additionally or alternatively, y may be selected from the range of < 19, such as from the range of < 17, especially from the range of < 15. Hence, y may be selected from the range of 1.5-19, such as from the range of 3-17, especially from the range of 4-15. Further, x may be selected from the range of > 10, such as from the range of > 12, especially from the range of > 13. Additionally or alternatively, x may be selected from the range of < 18, such as from the range of < 17, especially from the range of < 16. That is, x may be selected from the range of 10-18, such as from the range of 12-17, especially from the range of 13-16. Hence, in specific embodiments, the lenses may have a radius of curvature Rc; wherein Rc= Ro— 2024PF80145

[0047] 16 x*W wherein Ro = y*di; wherein y may be a constant depending on a second beam divergence angle t ; wherein y may be selected from the range of 3-17 mm; and wherein x may be selected from the range of 12-17. Such a formula for the radius of curvature Rcmay facilitate that a modeled “ideal” radius of curvature Ro may be adjusted based on the production method and the desired second beam divergence angle $2, wherein different production methods may lead to different fillet widths Wf.

[0048] In embodiments, the radius of curvature Rcmay be selected from the range of > 1.3 mm, such as from the range of > 2.5 mm, especially from the range of > 3.4 mm. Additionally or alternatively, the radius of curvature Rcmay be selected from the range of < 40 mm, such as from the range of < 20 mm, especially from the range of < 15 mm. That is, the radius of curvature Rcmay be selected from the range of 1.3-40 mm, such as from the range of 2.5-20 mm, especially from the range of 3.4-15 mm. Hence, in specific embodiments, the radius of curvature Rcmay be selected from the range of 2.5-20 mm. Lenses having a radius of curvature Rcselected from the range of 2.5-20 mm may facilitate diffusing and / or shaping a first beam of light source light into a second beam of light source light having a top-hat profile (see below).

[0049] The lenses may have a single radius of curvature Rc. Lenses having a single radius of curvature Rcmay especially be referred to as “spherical lenses” (regardless of the (perpendicular) projected shape of the lens boundaries of the spherical lens on a plane parallel to the first and / or second major surface of the optical element arrangement). In embodiments, all lenses have of the lens arrangements have essentially the same radius of curvature Rc. Spherical lenses may have a semi-circular shape in a plane perpendicular to the first (and / or second) major surface of the optical element arrangement. Alternatively, for concave lenses, spherical lenses may comprise a semi-circular depression in a plane perpendicular to the first (and / or second) major surface of the optical element arrangement. In embodiments, all of the lenses in a lens arrangement may be spherical lenses. Further, all of the lenses in the optical element arrangement may be spherical lenses. Alternatively, at least some of the lenses may have a plurality of radii of curvature Rc(individually selected from the range of 1.3-40 mm, such as from the range of 2.5-20 mm, especially from the range of 3.4-15 mm). Especially, said at least some of the lenses may have a first radius of curvature Rcin a (geometrical) center of the lens, wherein the radius of curvature Rcmay deviate (radially) with increasing distance from the center of the lens. Lenses having a plurality of radii of curvature Rcmay especially be referred to as “aspherical lenses”. 2024PF80145

[0050] 17

[0051] Aspherical lenses may have a shape in a plane perpendicular to the first (and / or second) major surface of the optical element arrangement selected from the group comprising a hyperbolic shape, a parabolic shape, a semi-elliptical shape, an irregular curved shape, or a higher-order polynomial curved shape. Alternatively, for concave lenses, aspherical lenses may comprise a depression having a shape selected from the group comprising a hyperbolic shape, a parabolic shape, a semi-elliptical shape, an irregular curved shape, or a higher-order polynomial curved shape, in a plane perpendicular to the first (and / or second) major surface of the optical element arrangement. In embodiments, all of the lenses in a lens arrangement may be aspherical lenses. Further, all of the lenses in the optical element arrangement may be aspherical lenses. In embodiments, some of the lens arrangements may comprise (only) spherical lenses, and some of the lens arrangements may comprise (only) aspherical lenses. Further, a (single) lens arrangement may comprise a combination of spherical and aspherical lenses.

[0052] As indicated above, the k lens arrangements may each comprise (a plurality of lenses arranged in) a second array. The second array may comprise, such as be, a regular array. In such embodiments, k may be selected from the range of > 1, such as from the range of > 2. Alternatively, the second array may comprise, such as be, a (non-periodic) tessellation array. In such embodiments, k may be selected from the range of > 1, such as especially from the range of > 2. Hence, in specific embodiments, the second array may comprise (a) a regular array, wherein k > 1, or (b) a tessellation array, wherein k > 2. A regular array may provide the benefit that the optical element arrangement may be relatively easy to design. Alternatively, a tessellation array may provide a relatively more uniform second beam of light source light, wherein the second beam may optionally have a rotational symmetric circular beam distribution.

[0053] In embodiments wherein k > 2 may apply, the second arrays of the different lens arrangements may be different types of arrays (e.g., different types of regular arrays, different types of tessellation arrays, or a combination of regular and tessellation arrays). Yet, especially, in embodiments wherein k > 2 may apply, the second arrays of all lens arrangements may be the same type of array. The second array may be a regular array. Especially, the second array may be a regular x*y array. In such embodiments, x > 2 may apply, such as x > 3, especially x > 4. Additionally or alternatively, in such embodiments, x < 1000 may apply, such as x < 900, especially x < 800. Further, in embodiments, y > x, such as y > 1.1 *x, especially y > 1.5*x, wherein y may be an integer. In embodiments, the first regular array (of solid state light sources) may be a regular n*m array, and the second array 2024PF80145

[0054] 18 may be a regular x*y array, wherein x > n. The regular x*y array may have a second pitch p2. In embodiments, the average center-to-center distance di may define (such as be) the second pitch p2 of the lenses in the regular array. Hence, for a regular second array, p2 = di. In embodiments, pi / di may be an integer. Yet, in embodiments, the second array may be a regular array, wherein pi / di (i. e. , pi / p2) may be a non-integer. Especially, pi / di may be a noninteger when pi / di < 5, such as pi / di < 4, especially pi / di < 3, applies. Further, ps / di (i. e. , ps / p2) may be a non-integer. Especially, ps / di may be a non-integer when ps / di < 5, such as ps / di < 4, especially ps / di < 3, applies. Hence, in specific embodiments, the second array may be a regular x*y array, wherein x > 2 and y > x; wherein the average center-to-center distance di may define a second pitch p2 of the lenses in the regular array; and wherein for pi / di < 4 applies that pi / di is a non-integer. An optical element arrangement comprising a regular array may be easier to design than an optical element arrangement comprising a tessellation array. Further, a regular array wherein pi / di may be a non-integer for pi / di < 4 may facilitate providing a second beam having a more rotational symmetric circular beam distribution.

[0055] The lenses in the regular array may have a lens shape. The lens shape may especially be determined by a (perpendicular) projection of the boundaries of the lens on a plane parallel to (and intersecting) the regular array (and parallel to the first and / or second major surface of the optical element arrangement). The boundaries of a lens may especially be determined by the point(s) of physical coupling (via the one or more fillets) between lenses. That is, the boundaries between adjacent lenses in the array may (in a projection on a plane parallel to the first array and the first and / or second major surface of the optical element arrangement) define a lens shape of the lenses. The lens shape of a lens may be selected separately from the radius (or radii) of curvature of the lens. Hence, each lens may have a spherical or aspherical shape in a cross-section perpendicular to the first (and / or second) major surface of the optical element arrangement, and an individually selected lens shape in a plane parallel to the first (and / or second) major surface of the optical element arrangement. In embodiments, the lens shape may be selected from the group of a circular shape, an elliptical shape, and a regular (simple) polygonal shape, such as especially from the group of a circular and a regular (simple) polygonal shape. The regular (simple) polygonal shape may especially be selected from the group of a triangular shape, a rectangular shape, and a hexagonal shape. Hence, in specific embodiments, the lenses in the regular array may have a lens shape in a plane parallel to the regular array selected from the group of a circular shape, a triangular shape, a rectangular shape, and a hexagonal shape. Lenses having circular, triangular, rectangular, or hexagonal lens shape may especially be arranged (in the regular 2024PF80145

[0056] 19 array) with a high packing density. In specific embodiments, the array may comprise lenses with different lens shapes. In other embodiments, the lenses may all have essentially the same lens shapes and essentially the same (cross-sectional) dimensions.

[0057] Lenses with a circular lens shape may be arranged in the regular array according to one (or more) of a rectangular (e.g. square) grid, a triangular grid, and a hexagonal grid. Lenses with a triangular, rectangular, of hexagonal lens shape may be arranged in the regular array according to respectively a triangular, rectangular, or hexagonal grid. In embodiments, all of the lenses in the regular array may have the same lens shape. Alternatively, a first subset of lenses in the regular array may have a first lens shape, and a second subset of lenses in the regular array may have a second lens shape. In such embodiments, the lens shapes of the first and second subset of lenses may especially be individually selected from the group of regular (simple) polygonal shapes. Further, in such embodiments, lenses from the second subset may be configured surrounded (within the regular array) by lenses from the first subset, wherein the lenses from the second subset may be smaller than the lenses from the first subset, and wherein the lenses from the first subset may have the second pitch p2. For example, the lenses from the first subset may have an octagonal lens shape, and may be arranged (with the second pitch p2) according to a first rectangular, especially square, grid in the regular array, such that a set of four octagonal lenses arranged in a square may form a diamond-shaped opening in the center of the set. Further, the lenses from the second subset may have a square (or diamond) lens shape, and may be arranged according to a second square grid in the regular array, wherein each lens of the second subset is configured in an opening of the first square grid. Yet, especially, all lenses in the regular array may have the same lens shape, and may be arranged according to one of a triangular grid, a rectangular (e.g. square) grid, or a hexagonal grid. In embodiments, in a rectangular (non-square) grid, the lenses may be configured to refract the light source light incident on the lenses to a different degree in different (perpendicular) directions. Especially, in such embodiments, the lenses in the second array may be configured at a first average center-to-center distance dia in a primary direction, and at a second average center- to-center distance dib in a (perpendicular) secondary direction, wherein dia dib, and wherein the lenses may be configured to refract incident light source light to a different degree in the primary direction and the secondary direction. Yet, especially, the lenses may have a hexagonal lens shape, wherein the lenses may be arranged according to a hexagonal grid, and wherein the second array may be a regular translation array. 2024PF80145

[0058] 20

[0059] The optical element arrangement may comprise k lens arrangements, wherein each of the k lens arrangements may comprise a regular (second) array. In such embodiments, k > 2 may apply. Further, the lenses (of each of the k lens arrangements) may have a hexagonal lens shape. In such embodiments, the lenses in each of the k lens arrangements may have the same orientation. That is, the lenses in a first lens arrangement (of the k lens arrangements) may have a translational symmetry with the lenses of a second (adjacent) lens arrangement (of the k lens arrangements). Alternatively, the orientations of (lens translation vectors for) lenses of adjacent lens arrangements may be rotated by an angle ai with respect to each other (in a plane parallel to the k lens arrangements). Especially, a direction of the second pitch p2 in a first lens arrangement (of the k lens arrangements) may be configured at the angle ai with a direction of the second pitch p2 in an adjacent lens arrangement. In embodiments, ai > 10° may apply, such as ai > 15°, especially ai > 20°. Additionally or alternatively, ai < 60° may apply, like ai < 55°, such as ai < 45°, especially ai < 35°. Hence, in embodiments, 10° < ai < 60°, like 10° < ai < 55°, such as 15° < ai < 45°, especially 20° < ai < 35°. In specific embodiments, the lenses may have a hexagonal lens shape, and ai may be selected from the range of 15°-45°, such as (essentially) 15°, or such as (essentially) 30°, or such as (essentially) 45°. Alternatively, the lenses may have a triangular lens shape, and ai may be (essentially) 60°. Alternatively, the lenses may have a square lens shape, and ai may be (essentially) 45°, or (essentially) 22.5°. Yet, in specific embodiments, the optical element arrangement may comprise the k lens arrangements, wherein k > 2; wherein the lenses may have a hexagonal lens shape; and wherein the orientations of lenses of adjacent lens arrangements may be rotated by an angle ai with respect to each other; wherein 15° < ai < 45°. An optical element arrangement wherein the lenses of adjacent lens arrangements have the same orientation may result in a second beam of light source light having a shape (in a cross-section of the second beam) at least approximating the shape of the lenses (i.e., hexagonal lenses may result in an (approximately) hexagonal second beam). Yet, by rotating the orientations of lenses of adjacent lens arrangements, a more rotationally symmetric circular second beam may be provided. Especially, rotating the hexagonal lenses by an angle ai of (essentially) 15° or (essentially) 45° may provide a more rotationally symmetric circular second beam.

[0060] In (alternative) embodiments, as indicated above, the second array may be a (non-periodic) tessellation array. In such embodiments, the optical element arrangement may especially comprise k lens arrangements, wherein k > 1, especially k > 2, may apply. Further, in such embodiments, the k lens arrangements may be arranged in a third regular array. The k 2024PF80145

[0061] 21 lens arrangements may be configured in physical contact in the third regular array. Alternatively, the k lens arrangements may be configured physically coupled, yet spaced apart (i.e., physically separated), in the third regular array. The k lens arrangements may be arranged in the third regular array according to one of a triangular grid, a rectangular (e.g. square) grid, and a hexagonal grid, such as especially according to a square grid. Hence, in embodiments, the k lens arrangements may have a cross-sectional shape (in a plane parallel to and intersecting the third regular array) selected from the group of a circular shape, a triangular shape, a rectangular (e.g. square) shape, and a hexagonal shape, such as especially a square shape. The k lens arrangements may have an arrangement pitch pain the third regular array. In embodiments, the arrangement pitch pamay be selected from the range of > 1.5 mm, such as from the range of > 2 mm, especially from the range of > 5 mm, like from the range of > 10 mm. Additionally or alternatively, the arrangement pitch pamay be selected from the range of < 50 mm, such as from the range of < 40 mm, especially from the range of < 30 mm. In embodiments, the k lens arrangements may have the arrangement pitch pain one or two (orthogonal) directions in the third array. As indicated above, each of the k lens arrangements in the third regular array may comprise a second array, wherein the second array may be a (non-periodic) tessellation array. The (non-periodic) tessellation array may especially be selected from the group comprising an irregular ring tessellation array, a phyllotaxis tessellation array, a rotated hexagonal tessellation array, a Hirschhom tessellation array, a polycrystal tessellation array, a spiral tessellation array, and a self-avoiding random tessellation array. Hence, in specific embodiments, the second array may be a tessellation array, wherein the k lens arrangements may be arranged in a third regular array; wherein the tessellation array may be selected from the group comprising an irregular ring tessellation array, a phyllotaxis tessellation array, a rotated hexagonal tessellation array, a Hirschhom tessellation array, a poly crystal tessellation array, a spiral tessellation array, and a selfavoiding random tessellation array. A tessellation array may facilitate providing a rotational symmetric circular second beam without having to rotate the orientation of lenses in adjacent lens arrangements. Further, an optical element arrangement comprising k tessellation arrays may be more decorative than an optical element arrangement comprising k regular arrays.

[0062] In embodiments, each of the k lens arrangements may comprise an individually selected type of tessellation array, wherein at least two of the k lens arrangements may comprise a different type of tessellation array. Alternatively, each of the k lens arrangements may comprise the same type of tessellation array. Further, in embodiments, the shape, orientation, and position of the lenses in the tessellation array may 2024PF80145

[0063] 22 be the same for each of the k lens arrangements. That is, the tessellation arrays of the k lens arrangements may be non-rotated and non-mirrored copies of each other. Alternatively, the tessellation arrays of adjacent lens arrangements may be mirror images of each other. Especially, (the tessellation array of) a first lens arrangement of the k lens arrangements may be a mirror image of (the tessellation array of) at least one adjacent lens arrangement (in the third regular array). Hence, in specific embodiments, a first lens arrangement of the k lens arrangements may be a mirror image of at least one adjacent lens arrangement. Having a first lens arrangement be a mirror image of an adjacent lens arrangement may provide the benefit that at a boundary between said adjacent lens arrangements, a (vertical) discontinuity (in a direction perpendicular to the first and / or second major surface of the optical element arrangement) between (the heights ol) adjacent lenses may be reduced (especially essentially eliminated), thereby providing a more gradual (or “smoother”) transition between the adjacent lens arrangements.

[0064] Further, in embodiments, the first lens arrangement (of the k lens arrangements) may be a mirror image of all adjacent lens arrangements (in the third regular array). For instance, in a third regular array comprising a rectangular (e.g. square) grid, the first lens arrangement may have four adjacent lens arrangements: one above, one below, one to the left, and one to the right of the first lens arrangement. In such embodiments, the lens arrangement above the first lens arrangement may be identical to the lens arrangement below the first lens arrangement, and the lens arrangement to the left of the first lens arrangement may be identical to the lens arrangement to the right of the first lens arrangement. Hence, in specific embodiments, the first lens arrangement may be a mirror image of all adjacent lens arrangements. Such a configuration may further reduce or prevent the appearance of discontinuities at the transitions between adjacent lens arrangements in the third regular array.

[0065] As indicated above, the optical element arrangement comprising the k lens arrangements (wherein the k lens arrangements may comprise one or more of a regular array and a tessellation array) may be configured to one or more of (i) diffuse and (ii) shape the first beam of light source light. Hence, the optical element arrangement may be configured to diffuse the first beam of light source light. Especially, the plurality of lenses may be configured to distribute a radiant flux of the (sub-beams ol) light source light over a larger (cross-sectional) area. Especially, as indicated above, the optical element arrangement may be configured to increase the first beam divergence angle 01 of the first beam of light source light, to provide a second beam of light source light having a second beam divergence angle 2024PF80145

[0066] 23 th. wherein $2 > Bi, such as $2 > 2* Bi, especially $2 > 4* BL Further, the optical element arrangement may be configured to reduce a variance in the radiant intensity distribution (in the angular domain) across a cross-section of the first beam of light source light, to provide a second beam of light source light having a radiant intensity varying < 15% over at least 75% of a cross-section of the second beam of light source light (in the angular domain). Hence, the term “diffuse the first beam of light source light” may herein (also) refer to homogenizing the first beam of light source light.

[0067] Further, the optical element arrangement may be configured to shape the first beam of light source light (into the second beam of light source light). Especially, the optical element arrangement may be configured to one or more of (i) decrease a ratio between a full width at 10% (of the) maximum (FW10M) and a FWHM of the second beam of light source light, and (ii) adjust the beam shape of the second beam of light source light (in a crosssection perpendicular to the second beam). Hence, (a radiant intensity distribution ol) the second beam of light source light (directly) downstream of the optical element arrangement may have a full width at 10% maximum (FW10M) in a cross-section perpendicular to (a propagation direction ol) the second beam of light source light (and in the angular domain). Further, (a radiant intensity distribution ol) the second beam of light source light (directly) downstream of the optical element arrangement may have a full width at half maximum (FWHM) in a cross-section perpendicular to (a propagation direction ol) the second beam of light source light (and in the angular domain). In embodiments, for the second beam of light source light may apply that FWHM / FW10M > 0.65, such as FWHM / FW10M > 0.7, especially FWHM / FW10M > 0.8, like FWHM / FW10M > 0.85. Hence, in specific embodiments, the second beam downstream of the optical element arrangement may have (a) a full width at half maximum FWHM, and (b) a full width at 10% maximum FW10M; wherein FWHM / FW10M > 0.7 may apply. A ratio of FWHM / FW10M > 0.7 may facilitate that a radiant intensity of the second beam of light source light may decrease sharply towards the edges of the second beam. Hence, such a ratio of FWHM / FW10M > 0.7 may provide a second beam having a top-hat profile, wherein a graph of a radiant intensity distribution of the light source light across a cross-section of the second beam (in the angular domain) may show two (approximately) vertical lines near the edges of the second beam, connected by an (essentially) horizontal line indicating a uniform (maximum) radiant intensity towards the center of the second beam.

[0068] The optical element arrangement may further be configured to shape the first beam of light source light by adjusting a cross-sectional shape of the first beam of light 2024PF80145

[0069] 24 source light. Especially, upstream of the optical element arrangement, the first beam of light source light may have a first cross-sectional beam shape in a cross-section perpendicular to a propagation direction of the first beam of light source light, wherein the optical element arrangement may be configured to shape the first beam into the second beam having a second cross-sectional beam shape in a cross-section perpendicular to a propagation direction of the second beam of light source light. In embodiments, the first cross-sectional beam shape may be determined by the shape of the first regular array. For instance, the solid state light sources may be configured in the first regular array according to a rectangular grid of 4x7 solid state light sources, such that the first beam of light source light (comprising 28 sub-beams) may have a rectangular first cross-sectional beam shape (with a first variance of > 30% over at most 75% of a cross-section of the first beam). The second cross-sectional beam shape may be determined by the number and type of second array(s) (e.g., a regular or tessellation array), the lens shape of the lenses in the second array, and the relative orientations of lenses in adjacent lens arrangements of the optical element arrangement. For instance, the optical element arrangement may comprise a single lens arrangement (i.e., k = 1) comprising a second regular array, wherein the lenses in the second regular array may have a hexagonal lens shape, and wherein the second beam of light source light may have a hexagonal second cross-sectional beam shape. Yet, especially, the optical element arrangement may be configured to shape the first beam of light source light into a second beam of light source light having a rotational symmetric (circular) beam distribution. Herein, the term “rotational symmetric circular beam distribution” may especially indicate that the second cross-sectional beam shape may approximate a circle. Further, the term “rotational symmetric circular beam distribution” may indicate that the second cross-sectional beam shape may be (virtually) rotated (in a plane perpendicular to the second beam) to any degree, wherein the second cross-sectional beam shape after rotation may be (essentially) equal to the second cross- sectional beam shape before rotation.

[0070] The term “approximate” and its conjugations herein, such as in “to approximate a shape”, refers to being nearly identical to, especially identical to, the following term, for example nearly identical to a circular segment or a semi-cylindrical shape. For example, the second cross-sectional beam shape may define a (filled) circle but for a defect. Similarly, for example, a (filled) circular shape defined by the second cross-sectional beam shape may not be perfectly round but slightly ellipsoidal. In particular, a second cross- sectional beam shape approximating a first shape may herein refer to: a first shape realization encompassing the second cross-sectional beam shape, wherein the first shape realization is 2024PF80145

[0071] 25 defined as the smallest encompassing shape of the second cross-sectional beam shape wherein the first shape realization has the shape of the first shape, wherein a ratio of the area of the first shape realization to the area of the second cross-sectional beam shape is < 1.2, especially < 1.1, such as < 1.05, especially < 1.02. For instance, the second cross-sectional beam shape may approximate a (filled) circular shape, wherein the first shape realization may be defined as the smallest encompassing circular shape of the second cross-sectional beam shape, wherein a ratio of the volume of the first shape realization to the volume of the second cross-sectional beam shape may be < 1.2, especially < 1.1, such as < 1.05, especially < 1.02, including 1. Further, if the dimensions of the first shape are defined, the term approximate may refer to the second cross-sectional beam shape and the first shape being superimposable such that an intersection between the second cross-sectional beam shape and the first shape covers n% of the second cross-sectional beam shape and n% of the first shape, wherein n is > 90%, such as > 95%, especially > 98%, such as > 99%, including (essentially) 100%. Further, the term “rotational symmetric” may herein indicate a rotational symmetry of order > 6, such as order > 12, especially order > 24.

[0072] Hence, the second beam may have a rotational symmetric circular beam distribution (having rotational symmetry of order > 6, such as order > 12, especially order > 24), wherein the second cross-sectional beam shape may approximate a circle. That is, starting from the (geometrical) center of the second cross-sectional beam shape and moving outwards in any direction, a graph of the radiant intensity distribution as a function of distance from the center may deviate < 15%, such as < 10%, especially < 5%, including (essentially) 0%, from a same graph obtained in any other direction from the center. Further, as indicated above, a radiant intensity of the light source light downstream of the optical element arrangement may vary < 15% over at least 75% of a cross-section of the second beam of light source light (in the angular domain). In embodiments, the second cross- sectional beam shape may thus especially approximate a (homogeneously filled) circle. Hence, in specific embodiments, the second beam may have a rotational symmetric circular beam distribution in a cross-section of the second beam. A rotational symmetric circular beam distribution may facilitate that, upon irradiating a surface with the second beam of light source light, the irradiated area may receive a similar irradiance (intensity) throughout the irradiated area, thereby preventing “hot spots” and reducing (uneven) photodegradation of the surface. Further, a rotational symmetric circular beam distribution may provide more decorative lighting effects (e.g. spot lighting). 2024PF80145

[0073] 26

[0074] Hence, the optical element arrangement may be configured to one or more of (i) diffuse and (ii) shape the first beam of light source light into a second beam of light source light. In other words, the optical element arrangement may be configured to convert the first beam of light source light received by the optical element arrangement into a second beam of light source light. Upstream of the optical element arrangement, the light source light received by the optical element arrangement may especially be indicated as the first beam of light source light, whereas light emanating away from the optical element arrangement at another (opposite) side of the optical element arrangement (than where the first beam of light source light is received) may be indicated as the second beam of light source light. Optical axes of the first beam of light source light received by the optical element arrangement and of the second beam of light source light emanating away of the optical element arrangement may be parallel, such as especially colinear.

[0075] The second beam of light source light may be used to illuminate (and / or irradiate) objects as such, i.e., without further beam shaping. Alternatively, the second beam of light source light may be (further) shaped downstream of the optical element arrangement. For instance, the second beam divergence angle th of the second beam of light source light may be increased or reduced downstream of the optical element arrangement. Hence, in embodiments, the light generating system may comprise one or more second optical elements. The one or more second optical elements may especially comprise one or more optical elements selected from the group of lenses, prisms, dichroic beam splitters, polarizing beam splitters, (reflective) mirrors, light filters, and apertures. In embodiments, the one or more second optical elements may comprises one or more lenses, such as one or more condenser lenses. Hence, in specific embodiments, the light generating system may comprise a condenser lens. The condenser lens may be configured downstream of the optical element arrangement. Further, the condenser lens may have an effective focal length fc. In embodiments, the light generating system may comprise a plurality of condenser lenses, wherein the plurality of condenser lenses may have the effective focal length fc. The term “effective focal length” is known to the person skilled in the art, and may refer to the inverse of the optical power of the condenser lens. The effective focal length fcmay be selected from the range of > 1 mm, such as from the range of > 2 mm, especially from the range of > 5 mm. Additionally or alternatively, the effective focal length fcmay be selected from the range of < 200 mm, such as from the range of < 150 mm, especially from the range of < 100 mm.

[0076] Further, the second beam of light source light may have a half-angle a. The half-angle a may be determined in a cross-section of the second beam parallel to the 2024PF80145

[0077] 27 propagation direction, and may refer to the angle between a first line (along the propagation direction) indicating the maximum radiant intensity and a second line (along the propagation direction) indicating (the position ol) half of the maximum radiant intensity (wherein for a perfectly collimated beam the half-angle a would be zero). In embodiments, the second beam of light source light may have the half-angle a upstream of the condenser lens. In embodiments, the half-angle a may be equal to the second beam divergence angle O2. Hence, in embodiments, the half-angle a may be selected from the range of > 2°, such as from the range of > 5°, especially from the range of > 7°, like from the range of > 10°. Additionally or alternatively, the half-angle a may be selected from the range of < 25°, such as from the range of < 20°, especially from the range of < 17°, like from the range of < 15°. In embodiments, the condenser lens may be configured to generate an image spot (of the second beam having the half-angle a) in a focal plane of the condenser lens. At the image spot, the (angular) radiant intensity distribution of the second beam of light source light may be transformed into a spatial irradiance distribution. That is, in the image spot, the second cross- sectional beam shape may be transformed into a spatial beam shape (resembling the second cross-sectional beam shape of the second beam of light source light). Hence, in embodiments, the second beam may have a rotationally symmetric circular second cross-sectional beam shape, wherein the condenser lens may be configured to generate a (substantially) circular image spot (having rotational symmetry). Further, the image spot may have an (effective) radius n. The (effective) radius may be defined by half of the FWHM of the irradiance distribution in the focal plane of the condenser lens. Further, the (effective) radius ri may be defined by n = fc*tan(a). In embodiments, the (effective) radius n may be selected from the range of > 0.3 mm, such as from the range of > 1 mm, especially from the range of > 2 mm. Additionally or alternatively, the (effective) radius n may be selected from the range of < 20 mm, such as from the range of < 15 mm, especially from the range of < 10 mm. In embodiments, the irradiance may be (essentially) equal throughout the image spot.

[0078] Alternatively, the irradiance may vary across the image spot. Yet, especially, (moving across the image spot,) an irradiance of the image spot may vary < 20%, such as < 15%, especially < 10%, like < 5%, including (essentially) 0%, over at least 0.65*n, such as over at least 0.75*n, especially over at least 0.85*n. That, a minimum irradiance in (at least part ol) the image spot may differ < 20%, such as < 15%, especially < 10%, like < 5%, including (essentially) 0%, from the maximum irradiance in said (at least part of) the image spot. Hence, in specific embodiments, the second beam may have a half-angle a, and the light generating system may comprise a condenser lens; wherein the condenser lens may be 2024PF80145

[0079] 28 configured downstream of the optical element arrangement; wherein the condenser lens may have an effective focal length fc; wherein the condenser lens may be configured to generate an image spot with radius n in a focal plane of the condenser lens; wherein n = fi*tan(a); and wherein an irradiance of the image spot may vary < 15% over at least 0.75*n. Such a condenser lens may facilitate focusing the second beam of light source light into a smaller image spot. Yet, such a condenser lens may essentially not alter the top-hat profile of the second beam of light source light.

[0080] The solid state light sources may be configured to provide light source light having a suitable color point and / or a suitable correlated color temperature (CCT). In such embodiments, the light source light may be directly used in lighting applications. Alternatively, the solid state light sources may be configured to provide light source light having a first color point, and the light generating system may be configured to convert at least part of the light source light into light having a second color point, to provide system light having (one or more ol) a suitable color point, color gamut, CCT, and / or color rendering index (CRI). Especially, the solid state light sources may be configured to generate one or more of violet light and blue light. The term “violet light”, and similar terms, may especially relate to light having a wavelength in the range of about 380-440 nm. The term “blue light”, and similar terms, may especially relate to light having a wavelength in the range of about 440-490 nm. In embodiments, each solid state light source may be configured to generate light source light having (essentially) the same spectral power distribution (and intensity). Alternatively, at least two of the solid state light sources may be configured to generate light source light having different spectral power distributions (and / or intensities). Yet, in embodiments, each of the solid state light sources may be configured to generate light source light having a peak wavelength individually selected from the range of 380-490 nm, such as from the range of 400-490 nm, especially from the range of 420-470 nm.

[0081] Further, as indicated above, the light generating system may be configured to convert at least part of the light source light into light having a different spectral power distribution from the light source light. Especially, the light generating system may comprise a luminescent body. The luminescent body may be a layer, like a self-supporting layer. The luminescent body may also be a coating. The luminescent body may also comprise a luminescent coating on a support. Especially, the luminescent body may essentially be self- supporting. In embodiments, a luminescent material (see below) may be provided as luminescent body, such as a luminescent single crystal, a luminescent glass, or a luminescent ceramic body. Such body may be indicated as “converter body” or “luminescent body”. In 2024PF80145

[0082] 29 embodiments, the luminescent body may be a luminescent single crystal or a luminescent ceramic body. In other embodiments, the luminescent body may comprise a light transmissive body, wherein a luminescent material may be embedded. For instance, the luminescent body may comprise a glass body or polymeric body, with luminescent material embedded therein. The luminescent body may be transparent or light scattering. In embodiments, the luminescent body may be a (small) tile. The luminescent body may be configured downstream of the optical element arrangement. Further, the luminescent body may be configured downstream of the condenser lens. Especially, the luminescent body may be configured in the focal plane of the condenser lens (i.e., the second beam of light source light may be focused on the luminescent body). The luminescent body may comprise a luminescent material. The luminescent material may be any (combination ol) luminescent material (s) known in the art. Several suitable examples of luminescent materials are provided below, yet it should be noted that the invention is not limited to the luminescent materials provided below. The luminescent material may be configured to convert at least part of the light source light received by the luminescent material into luminescent material light. Especially, the luminescent material may be configured to convert > 50%, such as > 65%, especially > 80%, like > 95%, including (essentially) 100%, of the light source light received by the luminescent material into luminescent material light. In embodiments, the luminescent material light may comprise, such as be, one (or more) of green light, yellow light, orange light, and red light. The term “green light”, and similar terms, may especially relate to light having a wavelength in the range of about 490-560 nm. The term “yellow light”, and similar terms, may especially relate to light having a wavelength in the range of about 560-590 nm. The term “orange light”, and similar terms, may especially relate to light having a wavelength in the range of about 590-620 nm. The term “red light”, and similar terms, may especially relate to light having a wavelength in the range of about 620-780 nm. The luminescent body may be configured in the transmissive mode. Herein, the term “transmissive mode” may indicate that when at least part of the light source light is propagating in the same direction from the luminescent body as it was propagating to the luminescent body directly upstream of the luminescent body, it may have a direction overlapping with the direction in which the luminescent material light escapes from the light generating system. Yet, in alternative embodiments, the luminescent body may be configured in a reflective mode. Herein, the term “reflective mode” may indicate that when light source light is reflected at the luminescent body, it may have a direction overlapping with the direction in which the luminescent material light escapes from the system. Hence, in specific 2024PF80145

[0083] 30 embodiments, the light generating system may comprise a luminescent body, wherein the luminescent body may be configured downstream of the optical element arrangement; wherein the luminescent body may comprise a luminescent material; wherein the luminescent material may be configured to convert at least part of the light source light received by the luminescent material into luminescent material light. A light generating system comprising a luminescent body may facilitate providing light with a relatively broad spectral power distribution. Especially, a light generating system comprising a luminescent body may facilitate providing white light. 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 K and 20000 K, especially between 2700 K and 20000 K, for general lighting especially in the range of 2000-7000 K, such as in the range of 2700-6500 K. The CCT may especially be within about 15 SDCM (standard deviation of color matching) from the BBL (black body locus), especially within 10 SDCM from the BBL, such as within 5 SDCM from the BBL.

[0084] Further, the light generating system may comprise a diffuser element. The diffuser element may be configured downstream of the optical element arrangement. Further, the diffuser element may be configured downstream of the condenser lens. Especially, the diffuser element may be configured in the focal plane of the condenser lens (i.e., the second beam of light source light may be focused on the diffuser element). The diffuser element may be configured to diffuse (or scatter) at least part of the light source light received by the diffuser element into diffused light source light. Especially, the diffuser element may be configured to diffuse > 50%, such as > 65%, especially > 80%, like > 95%, including (essentially) 100%, of the light source light received by the diffuser element into diffused light source light. In embodiments, the diffuser element may be configured in the transmissive mode. Yet, in alternative embodiments, the diffuser element may be configured in a reflective mode. Hence, in specific embodiments, the light generating system may comprise a diffuser element, wherein the diffuser element may be configured downstream of the optical element arrangement; wherein the diffuser element may be configured to convert at least part of the light source light received by the diffuser element into diffused light source light. A light generating system comprising a diffuser element may facilitate reducing the intensity of the light source light in the system light, thereby improving eye safety of the light generating system. In embodiments, the light generating system may comprise one or more of the luminescent body and the diffuser element, such as (both) the luminescent body and the diffuser element. 2024PF80145

[0085] 31

[0086] The light generating system may optionally comprise one or more second solid state light sources. In embodiments, the light generating system may comprise a (single) second solid state light source. Alternatively, the light generating system may comprise a plurality of second solid state light sources. The plurality of second solid state light sources may be configured in a fourth regular array, such as a v*w array, wherein v > 1 and w > v may apply. In specific embodiments, the fourth regular array (of second solid state light sources) may be identical to the first regular array (of solid state light sources). Alternatively, the fourth regular array may differ from the first regular array in one or more of: (i) the number of light sources in one or more of the rows and columns of the array; (ii) the type of solid state light source; (iii) the pitch between light sources in the array (in one or more of a first direction and a second direction); (iv) the spectral power distribution of the light source light; and (v) a size of the area illuminated by a sub-beam of light source light. The one or more second solid state light sources may be configured to generate second light source light. In embodiments, the second light source light may have a second peak wavelength selected from the range of 380-490 nm, such as from the range of 400-490 nm, especially from the range of 420-470 nm. Hence, the second light source light may be one or more of violet light and blue light, such as especially blue light. Alternatively, the second light source light may have a second peak wavelength selected from the range of 590-780 nm, such as from the range of 600-700 nm, especially from the range of 610-650 nm. Hence, the second light source light may be one or more of orange light and red light, such as especially red light. Further yet, in embodiments the second light source light may have a second peak wavelength selected from the range of 490-590 nm, such as from the range of 500-580 nm, especially from the range of 510-560 nm. Hence, the second light source light may be one or more of green light and yellow light. In embodiments, the optical element arrangement may be configured in a light receiving relationship with the one or more second solid state light sources. Alternatively, the light generating system may comprise a second optical element arrangement, wherein the second optical element arrangement may be configured in a light receiving relationship with the one or more second solid state light sources. In (other) embodiments, the second light source light may (essentially) not be incident on an optical element arrangement. Yet, in embodiments, the light generating system may comprise a second optical element arrangement, wherein the second optical element arrangement may be configured in a light receiving relationship with the one or more second solid state light sources, and wherein one or more of the luminescent body and the diffuser element, such as 2024PF80145

[0087] 32 especially the diffuser element, may be configured downstream of (and in a light receiving relationship with) the second optical element arrangement.

[0088] In a first operational mode of the light generating system, the light generating system may be configured to generate system light. The system light may comprise one or more of the light source light, the luminescent material light, and the second light source light. Optionally, the system light may (further) comprise the diffused light source light. Especially, in the first operational mode of the light generating system, the system light may comprise the luminescent material light, and optionally the second light source light. As indicated above, one or more of the light source light and the second light source light may be violet and / or blue light, and the luminescent material light may be one or more of green light, yellow light, orange light, and red light. Further, as indicated above, the second light source light may be one of green light, yellow light, orange light, and red light. Further yet, as indicated above, the luminescent material may be configured to convert (essentially) all of the light source light received by the luminescent material into luminescent material light. Hence, in embodiments, the system light may be colored light, such as colored light having a color point selected from the CIE 1931 color space. Alternatively, in embodiments, the system light may be white light. Especially, in the first operational mode of the light generating system, the system light may be white light. The white system light may have a CCT selected from the range of 1500-15000 K, such as from the range of 1800-12000 K, especially from the range of 2000-10000 K. Hence, in specific embodiments, (the light generating system may comprise a luminescent body, wherein the luminescent body may be configured downstream of the optical element arrangement; wherein the luminescent body may comprise a luminescent material; wherein the luminescent material may be configured to convert at least part of the light source light received by the luminescent material into luminescent material light; and) the light generating system may further comprise one or more second solid state light sources; wherein the one or more second solid state light sources may be configured to generate second light source light; wherein in a first operational mode of the light generating system the light generating system may be configured to generate system light comprising the luminescent material light and second light source light; wherein the system light may be white light having a correlated color temperature selected from the range of 1800-12000 K. A light generating system providing white system light may be especially suitable for general lighting applications. Further, a light generating system comprising one or more second solid state light sources may facilitate that the luminescent material may convert (essentially) all of the (e.g. blue) light source light, wherein the second 2024PF80145

[0089] 33 solid state light sources may provide a blue component to the system light, thereby improving the intensity of the system light. Alternatively, the second light source light may be one of green light, yellow light, orange light, and red light, wherein the light generating system may not comprise the luminescent body, or wherein the luminescent material may be configured to convert < 95% of the light source light into luminescent material light.

[0090] As indicated above, suitable examples of luminescent materials will be provided below. The term “luminescent material” may herein refer to a material that can convert first radiation, especially one or more of UV radiation and blue radiation, into second radiation, especially visible light. Herein, UV (ultraviolet) may especially refer to a wavelength selected from the range of 190-380 nm, such as 200-380 nm, though other wavelengths may also be possible. The term “visible light”, and similar terms, refers to light having one or more wavelengths in the range of about 380-780 nm. In general, the first radiation and second radiation have different spectral power distributions, with the second radiation especially having a spectral power distribution at larger wavelengths than the first radiation (i.e. “down-conversion”). Hence, upon excitation with radiation, the luminescent material may emit radiation. Further, the term “luminescent material” may refer to phosphorescence and / or fluorescence. The term “luminescent material” may also refer to a plurality of different luminescent materials. Hence, the term “luminescent material” may in specific embodiments also refer to a luminescent material composition. Examples of possible luminescent materials are indicated below. Instead of the term “luminescent material” also the term “phosphor” may be applied, as is known to the person skilled in the art.

[0091] In embodiments, luminescent materials may be selected from garnets and nitrides, especially doped with trivalent cerium or divalent europium, respectively. The term “nitride” may also refer to oxynitride or nitridosilicate, etc. Alternatively or additionally, the luminescent material(s) may be selected from silicates, especially doped with divalent europium. The luminescent material may comprise a divalent europium comprising oxynitride luminescent material. Further, in embodiments, the luminescent material may comprise a divalent europium comprising nitride luminescent material.

[0092] The luminescent material may comprise a cerium comprising garnet luminescent material of the type AsBsOnT'e. wherein A comprises one or more of yttrium (Y), lanthanum (La), gadolinium (Gd), terbium (Tb) and lutetium (Lu), and wherein B comprises one or more of aluminum (Al), gallium (Ga), indium (In), and scandium (Sc); and wherein the light source light may comprise blue light. Embodiments of garnets especially include A3B5O12 garnets, wherein A comprises at least Y or Lu, and wherein B comprises at 2024PF80145

[0093] 34 least Al. Such garnets may be doped with cerium (Ce), with praseodymium (Pr) or a combination of Ce and Pr. Further, B and O may at least partly be replaced by Si and N. The term “:Ce”, indicates that part of the metal ions (i.e. in the garnets: part of the “A” ions) in the luminescent material is replaced by Ce. This is known to the person skilled in the art.

[0094] The luminescent material may comprise a luminescent material of the type A3SieNii:Ce3+, wherein A comprises one or more of Y, La, Gd, Tb and Lu, such as in embodiments one or more of La and Y. The luminescent material may alternatively or additionally comprise one or more of MS:Eu2+and / or I LSisb- Eu2and / or MAISiN.vEu2and / or Ca2AlSi3O2Ns:Eu2+, etc., wherein M comprises one or more of Ba, Sr and Ca, especially in embodiments at least Sr.

[0095] The term “luminescent material” herein especially relates to inorganic luminescent materials. Alternatively or additionally, also other luminescent materials may be applied. For instance quantum dots and / or organic dyes may be applied and may optionally be embedded in transmissive matrices like e.g. polymers, like PMMA, or poly siloxanes, etc.

[0096] In embodiments, the luminescent material may comprise a luminescent material of the type Mi-xLi3-2yAli+2y-zSizO4-4y-zN4y+z:Eux, wherein M may comprise one or more of magnesium (Mg), calcium (Ca), strontium (Sr), and barium (Ba). Luminescent materials of the type Mi-xLi3-2yAli+2y-zSizO4-4y-zN4y+z:Eux may be indicated as SLA-type phosphors, and may be described in US2021171827A1, which is hereby herein incorporated by reference. In SLA-type phosphors, x may be selected from the range of 0 < x < 0.1, such as from the range of 0.0005 < x < 0.08, especially from the range of 0.001 < x < 0.05. Further, y may be selected from the range of 0 < y < 1, such as from the range of 0 < y < 0.75, especially from the range of 0 < y < 0.6. Additionally, z may be selected from the range of 0 < z < 0.1, such as from the range of 0 < z < 0.07, especially from the range of 0 < z < 0.05. The luminescent material may further comprise a SiAlON phosphor, such as selected from the group comprising (a) Sii2-m-nAlm+nOnNi6-n:Eu2+(a-SiA10N), (b) Sir, nAlnOnNsn:Eu2+, wherein 0 < n < 4.2 (P-SiAlON), and (c) Si2-nAlnOi+nN2-n:Eu2+, wherein 0 < n < 0.2 (O-SiAlON).

[0097] The luminescent material may comprise a tetravalent manganese-comprising luminescent material, i.e., a luminescent material doped with tetravalent manganese. Especially, in embodiments, the luminescent material may comprise a luminescent material of the type M’xM2-2xAXe:Mn4+, wherein M’ comprises an alkaline earth cation, M comprises an alkaline cation, and x may be selected from the range of 0-1, wherein A comprises a tetravalent cation, for instance comprising one or more of silicon and titanium, and wherein 2024PF80145

[0098] 35

[0099] X comprises a monovalent anion, at least comprising fluorine. The alkaline earth cation M’ may comprise one or more of magnesium (Mg), strontium (Sr), calcium (Ca), and barium (Ba), especially one or more of Sr and Ba. Further, the alkaline cation M may comprise one or more of sodium (Na), potassium (K), rubidium (Rb), ammonium (NFU+), lithium (Li), and cesium (Cs), such as at least K, or such as at least Rb. In embodiments, A may comprise a tetravalent cation, and preferably at least comprises silicon. A may (further) comprise one or more of titanium (Ti), germanium (Ge), stannum (Sn) and zinc (Zn). The monovalent anion X may comprise fluorine (F), chlorine (Cl), bromine (Br), and iodine (I), such as at least F. The luminescent material may be coated, as described in WO2013121355A1.

[0100] Here below, some general embodiments relating to the light source are provided. The term “light source” may in principle relate to any light source known in the art. In a specific embodiment, the light source may comprise a solid state light source (such as a LED or laser diode). The term “light source” may also refer to a chip scale package (CSP) and / or a chip scale packaged (CSP) LED. A CSP may comprise a single solid state die (such as a LED) with provided thereon a luminescent material comprising layer. The term “light source” may also refer to a midpower package. A midpower package may comprise one or more solid state die(s), optionally covered by a luminescent material comprising layer. The die dimensions may be < 2 mm, such as in the range of e.g. 0.2-2 mm. Herein, the term “light source” may also refer to mini LEDs or micro LEDs, such as especially micro LEDs or “microLEDs”. Herein, the term mini LED refers to solid state light sources having (die) dimensions, especially length and width, selected from the range of 0.1-1 mm. Further, the term micro LED refers to solid state light sources having (die) dimensions, especially length and width, selected from the range of < 100 pm.

[0101] The term “light source” may refer to a semiconductor light-emitting device, such as an LED, a resonant cavity LED (RCLED), a vertical cavity laser diode (VCSELs), an edge emitting laser, etc... The term “light source” may also refer to an organic LED (OLED), such as a passive-matrix (P MOLED) or an active-matrix (AMOLED). In an embodiment, the solid state light source may be selected from the group of a LED, a laser diode, a superluminescent diode, or a multi -junction LED.

[0102] The light source may be configured to provide primary radiation, which is used as such, such as e.g. a blue light source, like a blue LED. Such LEDs may be indicated as direct color LEDs. In other embodiments, the light source may be configured to provide primary radiation and part of the primary radiation may converted into secondary radiation (e.g. by a luminescent material). Secondary radiation may be based on conversion by a 2024PF80145

[0103] 36 luminescent material. The luminescent material may be comprised by the light source, such as an LED with a luminescent material layer or dome. Such LEDs may be indicated as phosphor converted LEDs or PC LEDs.

[0104] In embodiments, the solid state light sources may be laser light sources. The term “laser light source” especially refers to a laser. Such laser may be configured to generate laser light source light having one or more wavelengths in the UV, visible, or infrared. The term “laser” especially refers to a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. In embodiments, the term “laser” may refer to a solid-state laser. In specific embodiments, the terms “laser” or “laser light source”, or similar terms, may refer to a laser diode. Hence, in embodiments the solid state light sources may comprise laser diodes. In embodiments, the term “laser” may refer to one or more of cerium doped lithium strontium (or calcium) aluminum fluoride (Ce:LiSAF, Ce:LiCAF), chromium doped chrysoberyl (alexandrite) laser, chromium ZnSe (CrZnSe) laser, divalent samarium doped calcium fluoride (Sm:CaF2) laser, Er:YAG laser, erbium doped and erbium-ytterbium codoped glass lasers, F-Center laser, holmium YAG (Ho:YAG) laser, Nd:YAG laser, NdCrYAG laser, neodymium doped yttrium calcium oxoborate Nd:YCa4O(BO3)s or Nd:YCOB, neodymium doped yttrium orthovanadate (Nd:YVO4) laser, neodymium glass (Nd:glass) laser, neodymium YLF (Nd:YLF) solid-state laser, promethium 147 doped phosphate glass (147Pm3+:glass) solid-state laser, ruby laser (AhO3:Cr3+), thulium YAG (Tm:YAG) laser, titanium sapphire (Ti:sapphire; AhO3:Ti3+) laser, trivalent uranium doped calcium fluoride (U:CaF2) solid-state laser, Ytterbium doped glass laser (rod, plate / chip, and fiber), Ytterbium YAG (Yb:YAG) laser, Yb2Os (glass or ceramics) laser, etc. In embodiments, the term “laser” may refer to one or more of a semiconductor laser diodes, such as GaN, InGaN, AlGalnP, AlGaAs, InGaAsP, lead salt, vertical cavity surface emitting laser (VCSEL), quantum cascade laser, hybrid silicon laser, etc. The term “laser”, and similar terms, may thus refer to a solid state laser based on a crystalline or glass body doped with ions, like transition metal ions and / or lanthanide ions, to a fiber laser, to a photonic crystal laser, to a semiconductor laser (laser diode or diode laser), etc.

[0105] In embodiments, laser light sources may be arranged in a laser bank. The laser bank may in embodiments comprise heat sinking and / or optics (e.g. a lens to collimate the laser light). Hence, in embodiments lasers in a laser bank (or “laser array bank”) may share the same optics. Hence, in specific embodiments, the first (and / or fourth) regular array of (second) solid state light sources may be (part ol) a laser bank. 2024PF80145

[0106] 37

[0107] The sub-beams (of light source light) may be focused or collimated beams of (laser) light source light. The term “focused” may especially refer to converging to a small spot. Focusing (of the laser light source light) may be executed with one or more optics, such as especially two (focusing) lenses. Collimation may be executed with one or more (other) optics, like collimation elements, such as lenses and / or parabolic mirrors. In embodiments, the sub-beam of (laser) light source light may be relatively highly collimated, such as < 2° FWHM, like < 1° FWHM, especially < 0.5° FWHM.

[0108] 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, accent lighting systems, spot lighting systems, theater lighting systems, fiber-optics application systems, projection systems, self-lit display systems, pixelated display systems, segmented display systems, warning sign systems, medical lighting application systems, indicator sign systems, decorative lighting systems, portable systems, automotive applications, (outdoor) (road) lighting systems, urban lighting systems, green house lighting systems, horticulture lighting, digital projection, or LCD backlighting. The light generating system (or luminaire) may be part of or may be applied in e.g. optical communication systems or disinfection systems.

[0109] In yet a further aspect, the invention also provides a lamp or a luminaire comprising the light generating system as defined herein. The luminaire may further comprise a housing, optical elements, louvres, etc.. The lamp or luminaire may comprise a housing enclosing the light generating system. The lamp or luminaire may comprise a light window in the housing or a housing opening, through which the system light may escape from the housing. In yet a further aspect, the invention also provides a projection device comprising the light generating system as defined herein. 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. The projection device may include one or more light generating systems such as described herein. Hence, in an aspect the invention also provides a lighting device selected from the group of a lamp, a luminaire, a projector device, a disinfection device, a photochemical reactor, and an optical wireless communication device, comprising the light generating system as defined herein. Further, in an aspect the invention provides a lighting device selected from the group of a search light, an automotive lighting device, and a stage lighting device, comprising the light generating system as defined herein. Especially, in a second aspect, the invention provides a lighting device selected from the group of a lamp, a luminaire, a projector device, a disinfection 2024PF80145

[0110] 38 device, a photochemical reactor, a search light, an automotive lighting device, a stage lighting device, and an optical wireless communication device, comprising the light generating system as defined herein. The lighting device may comprise a housing or a carrier, configured to house or support, one or more elements of the light generating system.

[0111] The terms “light” and “radiation” are herein interchangeably used, unless clear from the context that the term “light” only refers to visible light. The terms “light” and “radiation” may thus refer to UV radiation, visible light, and IR radiation. In specific embodiments, especially for lighting applications, the terms “light” and “radiation” refer to (at least) visible light.

[0112] BRIEF DESCRIPTION OF THE DRAWINGS

[0113] 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:

[0114] Figs. 1A-1C schematically depict an embodiment of the light generating system;

[0115] Fig. 2 schematically depicts an embodiment of the first beam of light source light;

[0116] Fig. 3 schematically depicts an embodiment of the second beam of light source light;

[0117] Fig. 4 schematically depicts a further embodiment of the light generating system; and

[0118] Fig. 5 schematically depicts an embodiment of the lighting device.

[0119] The schematic drawings are not necessarily to scale.

[0120] DETAILED DESCRIPTION OF THE EMBODIMENTS

[0121] Fig. 1A schematically depicts an embodiment of the light generating system 1000. The light generating system 1000 may comprise a first regular array 500 of (a plurality of) solid state light sources 10 and an optical element arrangement 2000. The first regular array 500 may especially be an n*m array, wherein n > 1 and m > n. In embodiments, n + m > 4. The first regular array 500 of solid state light sources 10 may have a first pitch pi in a first direction. Further, the first regular array 500 of solid state light sources 10 may be configured to generate a first beam 5 of light source light 11. The optical element arrangement 2000 may be configured in a light receiving relationship with the first regular 2024PF80145

[0122] 39 array 500 of solid state light sources 10. Further, the optical element arrangement 2000 may comprise k lens arrangements 400. In embodiments, k > 1. Further, each lens arrangement 400 may comprise a plurality of lenses 30 arranged in a second array 600. The plurality of lenses 30 in each lens arrangement 400 may have an (per lens arrangement 400 individually selected) average center-to-center distance di. In embodiments, pi / di > 1.4. The optical element arrangement 2000 may be configured to one or more of (i) diffuse and (ii) shape the first beam 5 of light source light 11 into a second beam 6 of light source light 11 (see Fig. 3).

[0123] The second array 600 may be a regular array 610 (as depicted in Fig. 1 A), wherein k > 1. Alternatively, the second array 600 may be a (non-periodic) tessellation array 620 (as depicted in Fig. IB), wherein k > 2. Further, the solid state light sources 10 may comprise one or more of laser diodes, superluminescent diodes, and stacked junction light emitting diodes. Additionally, the light source light 11 from each of the solid state light sources 10 may be configured to illuminate an area 9 with a first equivalent circular diameter Di on a first major surface 2001 of the optical element arrangement 2000. The first equivalent circular diameter Di may especially be defined by a full width at half maximum of an irradiance distribution of the light source light 11 on the first major surface 2001. In Fig. 1A and Fig. IB, the sub-beams of light source light 11 are configured to illuminate an ellipsoidal area, and for illustration purposes an area diameter Da- indicating the diameter of the area 9 in that direction - is indicated. In embodiments, an area diameter Damay be determined for every direction in a rotation about the center of the illuminated area 9, wherein an average diameter of the area diameters Damay define the equivalent circular diameter Di. In embodiments, di / Di < 3 may apply.

[0124] The lenses 30 may be configured on the first major surface 2001 of the optical element arrangement 2000. Additionally or alternatively, the lenses 30 may be configured on a second major surface 2002 of the optical element arrangement 2000. The second major surface 2002 may especially be configured downstream of the first major surface 2001. Further, the lenses 30 (in the lens arrangements 400) may be physically coupled via one or more fillets 40. The fillets 40 may have fillet widths Wf (in between two adjacent lenses 30). In embodiments, the fillet widths Wf may be (for each fillet) individually selected from the range of Wf / di < 0.1. The insert in Fig. 1A depicts a magnification of a cross-section of a pair of lenses 30, taken along the dotted line. As depicted, the fillets 40 may especially form a concave transition from one lens 30 to another lens 30. Further, the lenses 30 may have a radius of curvature Rc. In embodiments, Rc= Ro- wherein Ro = y*di, and y may be a 2024PF80145

[0125] 40 constant depending on a second beam divergence angle $2. In embodiments, y may be selected from the range of 3-17 mm. Further, in embodiments, x may be selected from the range of 12-17. In embodiments, the radius of curvature Rcmay be selected from the range of 2.5-17 mm. Reference do indicates the largest thickness of the optical element arrangement 2000 in a cross-section of the optical element arrangement 2000 perpendicular to the first major surface 2001 and the second major surface 2002.

[0126] The first regular array 500 may further have a third pitch ps in a second direction (orthogonal to the first direction). In embodiments, ps > pi. Further, in embodiments, di > 0.5 mm. Especially, in embodiments, 1.8 < pi / di < 10 may apply.

[0127] The second array 600 may be a regular x*y array 610, wherein x > 2 and y > x. In such embodiments, the average center-to-center distance di may define a second pitch p2 of the lenses 30 in the regular array 610. Further, in a regular array 610, for pi / di < 4 may apply that pi / di is a non-integer. The lenses 30 in the regular array 610 may have a cross- sectional lens shape in a plane parallel to (and intersecting) the regular array 610 selected from the group of a circular shape, a triangular shape, a square shape, and a hexagonal shape. The cross-sectional lens shape may especially be defined by the boundaries between lenses 30 in the regular array 610.

[0128] Further, the optical element arrangement 2000 may comprise the k lens arrangements 400 (each comprising a regular array 610), wherein k > 2. That is, the optical element arrangement 2000 may comprise > 2 regular arrays 610. The lenses 30 (of each lens arrangement 400) may in such embodiments especially have a hexagonal cross-sectional lens shape. Further, the orientations of (lens translation vectors for) lenses 30 of adjacent lens arrangements 400 may be rotated by an angle ai with respect to each other (in a plane parallel to the k lens arrangements 400). Especially, a direction of the second pitch p2 in a first lens arrangement 400 may be configured at the angle ai with a direction of the second pitch p2 in an adjacent lens arrangement 400. In embodiments, 15° < ai < 45° may apply.

[0129] Fig. IB schematically depicts a further embodiment of the light generating system 1000. The second array 600 may be a (non-periodic) tessellation array 620. The (nonperiodic) tessellation array 620 may be selected from the group comprising an irregular ring tessellation array, a phyllotaxis tessellation array, a rotated hexagonal tessellation array, a Hirschhom tessellation array, a poly crystal tessellation array, a spiral tessellation array, and a self-avoiding random tessellation array. In such embodiments, the optical element arrangement 2000 may especially comprise > 2 lens arrangement 400 (i.e., k > 2). The k lens arrangements 400 may be arranged in a third regular array 700. Further, (in the third regular 2024PF80145

[0130] 41 array 700,) a first lens arrangement 400 of the k lens arrangements 400 may be a mirror image of at least one adjacent lens arrangement 400. Especially, the first lens arrangement 400 may be a mirror image of all adjacent lens arrangements 400 (in the third regular array 700). The lenses 30 in the tessellation array 620 may have a free-form and individually selected cross-sectional lens shape. Hence, the center-to-center distance dr (measured from geometrical center to geometrical center) between each set of adjacent lenses 30 may be individually selected, and may deviate from the average center-to-center distance di. The k lens arrangements 400 may have an arrangement pitch pain the third regular array 700.

[0131] Fig. 1C schematically depicts embodiments of the (non-periodic) tessellation array 620. The (non-periodic) tessellation array 620 may comprise an irregular ring tessellation array (I), a spiral tessellation array (II), a self-avoiding random tessellation array (III), a Hirschhom tessellation array (IV), a poly crystal tessellation array (V), a phyllotaxis tessellation array (VI), and a rotated hexagonal tessellation array (VII).

[0132] Fig. 2 schematically depicts an embodiment of the first regular array 500 and the first beam 5 of light source light 11. In embodiments, pi < 15 mm may apply. Further, (in the absence of the optical element arrangement 2000 and) within a distance of 100 cm from the first regular array 500, a radiant intensity IR of the light source light 11 may vary > 30% over at most 75% of a cross-section of the first beam 5 of light source light 11 (in the angular domain). The cross-section of the first beam 5 may be determined by a FWHM of the first beam 5 of light source light 11 in the angular domain. In Fig. 2, the variation in radiant intensity IR of the light source light 11 is depicted for two orthogonal cross-sections of the first beam 5: a first cross-section along the first direction (having the first pitch pi), and a second cross-section along the second direction (having the third pitch pfi. As depicted in Fig. 2, the radiant intensity IR may drop to (essentially) zero between two solid state light sources 10 in the first regular array 500. Hence, the radiant intensity distributions of adjacent sub-beams of light source light 11 may (essentially) not overlap.

[0133] Fig. 2 further schematically depicts a spatial irradiance distribution of the subbeams of light source light 11 in the illuminated areas 9 on the first major surface 2001 of the optical element arrangement 2000. In such embodiments, reference IR indicates the irradiance (intensity) in units W / mm2

[0134] Fig. 3 schematically depicts an embodiment of the second beam 6 of light source light 11. Directly downstream of the optical element arrangement 2000, a radiant intensity IR of the light source light 11 may vary < 15% over at least 75% of a cross-section of the second beam 6 of light source light 11 (wherein the cross-section of the second beam 6 2024PF80145

[0135] 42 may be determined by a FWHM of the second beam 6 of light source light 11). Similar as for the first beam 5 of light source light 11, the radiant intensity distribution across the second beam 6 of light source light 11 is depicted for two orthogonal cross-sections of the second beam 6: a first cross-section along the first direction (of the first regular array 500), and a second cross-section along the second direction (of the first regular array 500). The second beam 6 (directly) downstream of the optical element arrangement 2000 may (apart from a FWHM) further have a full width at 10% (of the) maximum FW10M. In embodiments, FWHM / FW10M > 0.7 may apply. Further, the second beam 6 may have a rotational symmetric circular beam distribution in a cross-section of the second beam 6.

[0136] Fig. 4 schematically depicts a further embodiment of the light generating system 1000. The light generating system 1000 may comprise a condenser lens 800. The condenser lens 800 may be configured downstream of the optical element arrangement 2000. Further, the condenser lens 800 may have an effective focal length fc. The condenser lens 800 may be configured to generate an image spot 8 with (an effective) radius ri in a focal plane of the condenser lens 800. Further, (upstream of the condenser lens 800,) the second beam 6 may have a half-angle a. In embodiments, n = fc*tan(a) may apply. Especially, an irradiance of the image spot 8 may vary < 15% over at least 0.75*n.

[0137] The light generating system 1000 may comprise a luminescent body 200. The luminescent body 200 may be configured downstream of the optical element arrangement 2000. Further, the luminescent body 200 may be configured downstream of the condenser lens 800, and in (or near) the focal plane of the condenser lens 800. Hence, the image spot 8 may be generated on a surface of the luminescent body 200. The luminescent body 200 may comprise a luminescent material 210. The luminescent material 210 may especially be configured to convert at least part of the light source light 11 received by the luminescent material 210 into luminescent material light 211. Fig. 4 schematically depicts an embodiment of the luminescent body 200 operated in the transmission mode. It should be noted the luminescent body may further be operated in the reflective mode.

[0138] In Fig. 4, the optical element arrangement 2000 is schematically represented by a rectangle. It should be noted that in reality the optical element arrangement 2000 may comprise the lenses 30 on one or more of the first major surface 2001 and the second major surface 2002, facilitating a non-planar (oscillating) appearance of said surface. In Fig. 4, the lenses 30 may be configured on the first major surface 2001, such that only the second major surface 2002 is indicated in this schematic drawing. 2024PF80145

[0139] 43

[0140] The light generating system 1000 may optionally further comprise one or more second solid state light sources 20. The second solid state light sources 20 may be configured to generate second light source light 21. Further, in a first operational mode of the light generating system 1000, the light generating system 1000 may be configured to generate system light 1001 comprising the luminescent material light 210 and optionally second light source light 21. The system light 1001 (in the first operational mode) may especially be white light having a CCT selected from the range of 1800-12000 K.

[0141] Fig. 5 schematically depicts an embodiment of a luminaire 2 comprising the light generating system 1000 as described above. 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. Fig. 5 also schematically depicts an embodiment of lamp 1 comprising the light generating system 1000. Reference 3 indicates a projector device or projector system, which may be used to project images, such as at a wall, which may also comprise the light generating system 1000. Hence, Fig. 5 schematically depicts embodiments of a lighting device 1200 selected from the group of a lamp 1, a luminaire 2, a projector device 3, a disinfection device, a photochemical reactor, and an optical wireless communication device, comprising the light generating system 1000 as described herein. In embodiments, such lighting device 1200 may be a lamp 1, a luminaire 2, a projector device 3, a disinfection device, or an optical wireless communication device. Fig. 5 also schematically depicts an embodiments of an outdoor light, or stage light, or stadium light. Fig. 5 also schematically depicts a vehicle, like an automobile, but this may also be a truck, a motor cycle, etc. etc., with one or more automotive lighting devices 4, e.g. headlights. These automotive lighting devices 4 may also comprise the lighting device 1200. Lighting device light escaping from the lighting device 1200 is indicated with reference 1201. Lighting device light 1201 may essentially consist of system light 1001, and may in specific embodiments be system light 1001. Reference 1300 refers to a space, e.g. a room. Reference 1305 refers to a floor and reference 1310 to a ceiling; reference 1307 refers to a wall.

[0142] 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 2024PF80145

[0143] 44 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.

[0144] 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.

[0145] The devices, 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, or systems in operation. 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. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

[0146] The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In 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. The invention also provides a control system that may control the device or system, or that may execute a mode of operation of the system. 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, or system, controls one or more controllable elements 2024PF80145

[0147] 45 of such device, or system. The invention further applies to a device, 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 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

2024PF8014546CLAIMS:

1. A light generating system (1000) comprising (i) a first regular array (500) of solid state light sources (10) and (ii) an optical element arrangement (2000), wherein: the first regular array (500) is an n*m array, wherein n > 1 and m > n; wherein n + m > 4; wherein the first regular array (500) of solid state light sources (10) has a first pitch (pi) in a first direction; wherein the first regular array (500) of solid state light sources (10) is configured to generate a first beam (5) of light source light (11); the optical element arrangement (2000) is configured in a light receiving relationship with the first regular array (500) of solid state light sources (10); wherein the optical element arrangement (2000) comprises k lens arrangements (400); wherein k > 1; wherein each lens arrangement (400) comprises a plurality of lenses (30) arranged in a second array (600); wherein the plurality of lenses (30) in each lens arrangement (400) have an average center-to-center distance (di); wherein pi / di > 1.4; the optical element arrangement (2000) is configured to one or more of (i) diffuse and (ii) shape the first beam (5) of light source light (11) into a second beam (6) of light source light (11); the second array (600) comprises (a) a regular array (610), wherein k > 1, or (b) a tessellation array (620), wherein k > 2; the solid state light sources (10) comprise one or more of laser diodes, superluminescent diodes, and stacked junction light emitting diodes; the light source light (11) from each of the solid state light sources (10) is configured to illuminate an area (9) with a first equivalent circular diameter Di on a first major surface (2001) of the optical element arrangement (2000); wherein the first equivalent circular diameter Di is defined by a full width at half maximum of an irradiance distribution of the light source light (11) on the first major surface (2001); and wherein di / Di < 3.

2. The light generating system (1000) according to claim 1, wherein di / Di < 2.

3. The light generating system (1000) according to one of the preceding claims, wherein the second array (600) is a regular x*y array (610), wherein x > 2 and y > x; wherein2024PF8014547 the average center-to-center distance di defines a second pitch p2 of the lenses (30) in the regular array (610); and wherein for pi / di < 4 applies that pi / di is a non-integer.

4. The light generating system (1000) according to claim 3, wherein the lenses (30) in the regular array (610) have a lens shape in a plane parallel to the regular array (610) selected from the group of a circular shape, a triangular shape, a rectangular shape, and a hexagonal shape.

5. The light generating system (1000) according to any one of the preceding claims 3-4, wherein the optical element arrangement (2000) comprises the k lens arrangements (400), wherein k > 2; wherein the lenses (30) have a hexagonal lens shape; and wherein the orientations of lenses (30) of adjacent lens arrangements (400) are rotated by an angle ai with respect to each other; wherein 15° < ai < 45°.

6. The light generating system (1000) according to any one of the preceding claims 1-2, wherein the second array (600) is a tessellation array (620), wherein the k lens arrangements (400) are arranged in a third regular array (700); wherein the tessellation array (620) is selected from the group comprising an irregular ring tessellation array, a phyllotaxis tessellation array, a rotated hexagonal tessellation array, a Hirschhom tessellation array, a poly crystal tessellation array, a spiral tessellation array, and a self-avoiding random tessellation array.

7. The light generating system (1000) according to claim 6, wherein a first lens arrangement (400) of the k lens arrangements (400) is a mirror image of at least one adjacent lens arrangement (400).

8. The light generating system (1000) according to any one of the preceding claims, wherein one or more applies of: the second beam (6) downstream of the optical element arrangement (2000) has (a) a full width at half maximum FWHM, and (b) a full width at 10% maximum FW10M; wherein FWHM / FW10M > 0.7;1.8 < pi / di < 10; and2024PF8014548 the lenses (30) are physically coupled via one or more fillets (40); wherein the fillets (40) have fillet widths Wf, wherein the fillet widths Wf are individually selected from the range of Wf / di < 0.1.

9. The light generating system (1000) according to claim 8, wherein the lenses(30) have a radius of curvature Rc; wherein Rc= Ro- -^-Lwherein Ro = y*di; wherein y is a constant depending on a second beam divergence angle O2; wherein y is selected from the range of 3-17; and wherein x is selected from the range of 12-17.

10. The light generating system (1000) according to claim 9, wherein the radius of curvature Rc is selected from the range of 2.5-20 mm.

11. The light generating system (1000) according to any one of the preceding claims, wherein one or more applies of: di > 0.5 mm; the first regular array (500) has a third pitch ps in a second direction; wherein ps > pi; and the second beam (6) has a rotational symmetric circular beam distribution in a cross-section of the second beam (6).

12. The light generating system (1000) according to any one of the preceding claims, wherein pi < 15 mm; wherein within a distance of 100 cm from the first regular array (500) of solid state light sources (10), in the absence of the optical element arrangement (2000), a radiant intensity of the light source light (11) varies > 30% over at most 75% of a cross-section of the first beam (5) of light source light (11); and wherein in the presence of the optical element arrangement (2000) a radiant intensity of the light source light (11) downstream of the optical element arrangement (2000) varies < 15% over at least 75% of a cross-section of the second beam (6) of light source light (11).

13. The light generating system (1000) according to any one of the preceding claims, wherein the second beam (6) has a half-angle (a); wherein the light generating system (1000) comprises a condenser lens (800); wherein the condenser lens (800) is configured downstream of the optical element arrangement (2000); wherein the condenser lens (800) has2024PF8014549 an effective focal length (fc); wherein the condenser lens (800) is configured to generate an image spot (8) with radius (n) in a focal plane of the condenser lens (800); wherein n = fc*tan(a); and wherein an irradiance of the image spot (8) varies < 15% over at least 0.75*n.

14. The light generating system (1000) according to any one of the preceding claims, wherein: the light generating system (1000) comprises a luminescent body (200), wherein the luminescent body (200) is configured downstream of the optical element arrangement (2000); wherein the luminescent body (200) comprises a luminescent material (210); wherein the luminescent material (210) is configured to convert at least part of the light source light (11) received by the luminescent material (210) into luminescent material light (211); and the light generating system (1000) further comprises one or more second solid state light sources (20); wherein the one or more second solid state light sources (20) are configured to generate second light source light (21); wherein in a first operational mode of the light generating system (1000) the light generating system (1000) is configured to generate system light (1001) comprising the luminescent material light (210) and second light source light (21); wherein the system light (1001) is white light having a correlated color temperature selected from the range of 1800-12000 K.

15. A lighting device (1200) selected from the group of a lamp (1), a luminaire (2), a projector device (3), a disinfection device, a photochemical reactor, a search light, an automotive lighting device (4), a stage lighting device, and an optical wireless communication device, comprising the light generating system (1000) according to any one of the preceding claims.

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