EMBEDDED PHOSPHOR CERAMIC TILE

Abstract

The invention provides an assembly (2000) comprising a luminescent body (200), a thermally conductive element (400), and a coating layer (500), wherein: the luminescent body (200) comprises a luminescent material (210), wherein the luminescent body (200) comprises a ceramic luminescent body, and wherein the luminescent body (200) comprises an external surface (220); the thermally conductive element (400) comprises metal material (410); at least 25% of the external surface (220) is in thermal contact with the thermally conductive element (400); and—the coating layer (500) is configured between the luminescent body (200) and the thermally conductive element (400).

Claims

1. An assembly comprising a luminescent body, a thermally conductive element, and a coating layer, wherein: the luminescent body comprises a luminescent material, wherein the luminescent body comprises a ceramic luminescent body, and wherein the luminescent body comprises an external surface; the thermally conductive element comprises metal material; at least 25% of the external surface is in thermal contact with the thermally conductive element; wherein the coating layer is configured between the luminescent body and the thermally conductive element; wherein the coating layer and the thermally conductive element are conformal to the luminescent body; wherein the thermally conductive element comprises supersonic particle deposited metal material; wherein 25-95% of the external surface is surrounded by the thermally conductive element; wherein the supersonic particle deposited metal material has a porosity selected from the range of 5-30%.

2. The assembly according to claim 1, wherein the supersonic particle deposited metal material has a porosity selected from the range of 5-20%.

3. The assembly according to claim 1, wherein the thermally conductive element may comprise a multilayer comprising the metal material, wherein a first layer of the multilayer has a first thickness and a first porosity, wherein a second layer of the multilayer has a second thickness and a second porosity, wherein the first layer is configured closer to the luminescent body than the second layer, and wherein p1<p2 or p2<p1.

4. The assembly according to claim 1, wherein thermally conductive element comprises a multilayer comprising the metal material, wherein a first layer of the multilayer has a first thickness and a first porosity p1, wherein a second layer of the multilayer has a second thickness and a second porosity p2, wherein the first layer is configured closer to the luminescent body than the second layer, wherein d1<d2 and wherein p1<p2.

5. The assembly according to claim 1, wherein the luminescent body comprises a luminescent ceramic body, and wherein more than 50% and up to 95% of the external surface is surrounded by the thermally conductive element.

6. The assembly according to claim 1, wherein the luminescent body has has a first volume V1, wherein the thermally conductive element has a second volume V2, wherein V2≥10*V1.

7. The assembly according to claim 1, wherein the luminescent body has a first face and a second face, wherein the first face and the second face define a height of the luminescent body, wherein: the entire second face is directed to the thermally conductive element and the entire first face is not directed to the thermally conductive element; or the entire second face is directed to the thermally conductive element except for one or more pinholes, and the entire first face is not directed to the thermally conductive element; or the entire second face is directed to the thermally conductive element and part of the entire first face is directed to the thermally conductive element; or the entire second face is directed to the thermally conductive element, except for one or more pinholes, and part of the entire first face is directed to the thermally conductive element.

8. The assembly according to claim 1, wherein the coating layer comprises a reflective layer, wherein the reflective layer is in contact with the luminescent body, and wherein the reflective layer has a reflection of at least 80% under perpendicular radiation for one or more wavelengths selected from one or more of the UV wavelength range and the visible wavelength range.

9. The assembly according to claim 8, wherein the coating layer has a thickness selected from the range of 1-1000 μm.

10. The assembly according to claim 8, wherein the coating layer comprises an adhesion layer, wherein the adhesion layer is in contact with the thermally conductive element.

11. The assembly according to claim 1, further comprising a light source configured to generate light source light, wherein the light source comprises a laser light source, wherein the light source is configured to irradiate with the light source light the luminescent body, wherein the luminescent material is configured to convert at least part of the light source light into luminescent material light; and wherein the luminescent material comprises a luminescent material of the type A.sub.3B.sub.5O.sub.12:Ce, wherein A comprises one or more of Y, La, Gd, Tb and Lu, and wherein B comprises one or more of Al, Ga, In and Sc.

12. The assembly according to claim 11, wherein the thermally conductive element comprises one or more of (i) a first protruding part configured as beam dump for part of the light source light, and (ii) a second protruding part configured as light source support.

13. A method for producing an assembly comprising a luminescent body, a thermally conductive element, and a coating layer, wherein the method comprises: providing the luminescent body comprising a luminescent material, wherein the luminescent body comprises an external surface; a deposition stage comprising: providing the coating layer to part of the external surface; providing the thermally conductive element comprising metal material to the coating layer by supersonic particle deposition.

14. The method according to claim 13, comprising: shielding part of the external surface with a mold element while leaving part of the external surface accessible; executing the deposition stage; and removing the mold element.

15. A lamp or a luminaire or a projector system comprising the assembly according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0135] 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:

[0136] FIGS. 1a-1b schematically depict some aspects;

[0137] FIGS. 2a-2b schematically depict some embodiments;

[0138] FIGS. 3a-3b schematically depict some further aspects; and

[0139] FIG. 4 schematically depicts some applications. The schematic drawings are not necessarily to scale.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0140] FIG. 1a schematically depicts some embodiments of an assembly 2000 comprising a luminescent body 200, a thermally conductive element 400, and an optional coating layer 500. Variant I comprises such coating layer 500 and by way of example, variant II does not comprise such coating layer. The luminescent body 200 comprises a luminescent material 210. Especially, the luminescent body 200 comprises a ceramic luminescent body. The luminescent body 200 comprises an external surface 220, i.e. the outer faces or surface. The luminescent body 200 may have a first face 221 and a second face 222, which may define a height Hl. Reference 223 indicates a side face. There may be one or more side faces 223, like one side face 223 in the case of a disc-like luminescent body 200 and four side faces 223 in the case of a cubic or bar-like or plate-like luminescent body 200. The second face 222 is directed to the thermally conductive element 400. The thermally conductive element 400 comprises metal material 410. Especially, at least 25% of the external surface 220 is in thermal contact with the thermally conductive element 400. Further, as shown in variant I the coating layer 500 may be configured between the luminescent body 200 and the thermally conductive element 400.

[0141] As schematically depicted, the (optional) coating layer 500 and the thermally conductive element 400 are conformal to the luminescent body 200.

[0142] Especially, in embodiments (see e.g. also FIG. 3), the thermally conductive element 400 comprises supersonic particle deposited metal material 410.

[0143] In embodiments, 25-95% of the external surface 220 is surrounded by the thermally conductive element 400.

[0144] FIG. 1b schematically also depict some variants. Here the aspect of the possible porosity of the thermally conductive element 400 or thermally conductive body is shown with two possible variants. The variant I may have an essentially homogeneous distribution of the porosity; variant II may have an inhomogeneous distribution of the porosity, leading in this variant to two layers.

[0145] In embodiments, the supersonic particle deposited metal material 410 has a porosity selected from the range of 10-20%. The pores are very schematically indicated. Reference 417 refers to the pores.

[0146] Referring to variant II in FIG. 1b, the thermally conductive element 400 may comprise a multilayer comprising the metal material 410. A first layer 411 of the multilayer 410 may have a first thickness dl and a first porosity p1. A second layer 412 of the multilayer 410 may have a second thickness d2 and a second porosity p2. In embodiments, the first layer 411 may be configured closer to the luminescent body 200 than the second layer 412. In embodiments, d1≥1 mm and/or d2≥1 mm. Further, in specific embodiments p1<p2.

[0147] FIG. 2a schematically depict some variants wherein more than 50% and up to 95% of the external surface 220 is surrounded by the thermally conductive element 400.

[0148] In embodiments, the luminescent body 200 has a first volume V1, wherein the thermally conductive element 400 has a second volume V2, wherein V2≥2*V1, especially wherein V2≥10*V1.

[0149] As indicated above, the luminescent body 200 has a first face 221 and a second face 222, wherein the first face 221 and the second face 222 define a height H1 of the luminescent body 200.

[0150] In variant I in FIG. 2a, the entire second face 222 is directed to the thermally conductive element 400 and the entire first face 221 is not directed to the thermally conductive element 400. In variant II in FIG. 2a, the entire second face 222 is directed to the thermally conductive element 400, except for one or more pinholes 405, and the entire first face 221 is not directed to the thermally conductive element 400. In variant III in FIG. 2a, the entire second face 222 is directed to the thermally conductive element 400 and part of the entire first face 221 is directed to the thermally conductive element 400. In variant IV in FIG. 2a, the entire second face 222 is directed to the thermally conductive element 400, except for one or more pinholes 405, and part of the entire first face 221 is directed to the thermally conductive element 400.

[0151] FIG. 2a also shows an embodiment of a light generating device 1000, comprising the assembly 2000 and a light source 100, configured to generate light source light 101, which can at least partly converted into luminescent material light 211. Such light generating device 1000 may provide device light 1001 comprising at least the luminescent material light 211 and optionally the light source light 101. Hence, FIG. 2a schematically depict embodiments of the assembly 2000, further comprising a light source 100 configured to generate light source light 101. Especially, the light source 100 comprises a laser light source, such as a laser diode, thought the light source 100 may also be an LED. The light source 100 is configured to irradiate with the light source light 101 the luminescent body 200, wherein the luminescent material 210 is configured to convert at least part of the light source light 101 into luminescent material light 211. In specific embodiments the luminescent material 210 comprises a luminescent material of the type A.sub.3B.sub.5O.sub.12:Ce, wherein A comprises one or more of Y, La, Gd, Tb and Lu, and wherein B comprises one or more of Al, Ga, In and Sc. The light source light 101 may be provided in embodiments via a pinhole 405. By way of example, variant IV comprises more than one pinhole 405. Further, by way of example some variants include a coating layer 500 and some do not. Especially, however, in general the coating layer 500 may be applied.

[0152] FIG. 2b schematically depict some embodiments of the coating layer.

[0153] In variant I of FIG. 2b, the coating layer 500 may comprise a reflective layer 510. The reflective layer 510 may comprise one or more of aluminum and silver. Especially, the reflective layer 510 is in contact with the luminescent body 200. In embodiments, the reflective layer 510 may have a reflection of at least 50% (especially at least 80%) under perpendicular radiation for one or more wavelengths selected from one or more of the UV wavelength range and the visible wavelength range. The reflective layer 510 may have a thickness d3.

[0154] In variant II of FIG. 2b, the coating layer 500 comprises reflective layer 510 and a protective layer 520. The protective layer may e.g. be aluminum (or silver). The thickness d4 may be selected from the range of 1-1000 μm, or smaller.

[0155] Hence, when using a relatively thick reflective layer 510, one may effectively obtain a protective layer having reflective properties. In variant III of FIG. 2b, the coating layer 500 may comprise a relatively thick reflective layer 510, such as having a thickness d3,d4 selected from the range of 1-1000 μm. The reflective layer 510 may e.g. comprise Al.

[0156] In variant IV of FIG. 2b, the coating layer 500 comprises an adhesion layer 530. The adhesion layer 530 may facilitate adhesion of the SPD layer 400. In embodiments, the adhesion layer 530 may comprises chromium. In embodiments, the adhesion layer 530 is in contact with the thermally conductive element 400. Further, in embodiments the adhesion layer has an adhesion layer thickness d5 selected e.g. from the range of 50-1000 nm.

[0157] In variant VI of FIG. 2b, the adhesion layer 510 is directly deposited on the (thick) reflective layer 510.

[0158] FIG. 3a schematically depicts an embodiment of a method for producing an assembly 2000 comprising a luminescent body 200, a thermally conductive element 400, and a coating layer. For the sake of clarity, the coating layer is not depicted, but such coating layer may be configured between the luminescent body and the thermally conductive element 400. Hence, such coating may be provided after the second stage in the drawing and before the third stage in the drawing. As indicated above, the coating layer may e.g. be provided by one or more of CVD and PVD, especially PVD. Further, the coating layer may comprise in embodiments a multi-layer, of which the two or more layers may be provided with independently selected deposition methods.

[0159] The method may comprise: (i) providing a mold 600 and the luminescent body 200 and configuring the latter in the right position, and (ii) a deposition stage (see also below). Hence, the method may comprise providing the luminescent body 200 comprising a luminescent material 210, wherein the luminescent body 200 comprises an external surface 220. Further, the method may comprise a deposition stage comprising (a) optionally providing the coating layer to part of the external surface 220, and (b) providing the thermally conductive element 400 comprising metal material 410 to the coating layer 500 (on the luminescent body 200)or to the luminescent body 200 by supersonic particle deposition.

[0160] In embodiments, the method may further comprise (a) providing the coating layer 500 to 25-95% of the external surface 220 by providing one or more of (ai) a reflective layer 510, wherein the reflective layer 510 comprises one or more of aluminum and silver, and wherein the reflective layer 510 is provided by (vapor) deposition of the reflective layer 510 on the external surface 220 (of the luminescent body 200); (aii) an adhesion layer 530, wherein the adhesion layer 530 comprises chromium, and wherein the adhesion layer 530 is provided by (vapor) deposition, and wherein the thermally conductive element 400 (comprising metal material 410) is provided on the adhesion layer 530 by supersonic particle deposition.

[0161] The coating layer 500 (and also the thermally conductive element 400) may cover 25-95 of the external surface 220, especially 40-90%, such as 50-85%, even more especially 60-80%. The higher the coverage, the better for thermal management. Further, a too high coverage may not be good for the efficiency, as luminescent light may less easily couple out from the luminescent body. Further, the area that can be irradiated should also not be too small.

[0162] As schematically depicted in FIG. 3a, the method may thus (also) comprise (a) shielding part of the external surface 220 (of the luminescent body 200) with a mold element 600 while leaving part of the external surface 220 accessible; (b) executing the deposition stage; and (c) removing the mold element 600.

[0163] In FIG. 3a also the assembly 2000 as produced is shown. It is also effectively shown that a mold 600 was chosen allowing to provide one or more of a support for the light source and a beam dump. Hence, a variant is shown wherein the thermally conductive element 400 comprises a first protruding part 450 configured as beam dump for part of the light source light 101. FIG. 3a also schematically depicts an embodiment of a second protruding part 460, which may especially be a sloped part. Hence, in embodiments the light source maybe configured such that an optical axis of the light source light is under an angle with a face, here the first face of the luminescent body selected from the range of e.g. larger than 30° but smaller than 90°.

[0164] FIG. 3b schematically depict an embodiment with two light sources. Especially, they may be configured to generate light source light 101 having different spectral power distributions.

[0165] FIG. 4 schematically depicts an embodiment of a luminaire 2 comprising the light generating device 1000 as described above. Reference 301 indicates a user interface which may be functionally coupled with the control system (not depicted) comprised by or functionally coupled to the lighting system 1000. FIG. 4 also schematically depicts an embodiment of lamp 1 comprising the light generating device 1000. Reference 3 indicates a projector device or projector system, which may be used to project images, such as at a wall.

[0166] The term “plurality” refers to two or more.

[0167] 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%.

[0168] The term “comprise” also includes embodiments wherein the term “comprises” means “consists of”.

[0169] 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”.

[0170] 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.

[0171] The devices, apparatus, or systems may herein amongst others be described during operation. As will be clear to the person skilled in the art, the invention is not limited to methods of operation, or devices, apparatus, or systems in operation.

[0172] 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.

[0173] In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

[0174] 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”.

[0175] The article “a” or “an” preceding an element does not exclude the presence of a plurality of such elements.

[0176] The invention further applies to a device, apparatus, or system comprising one or more of the characterizing features described in the description and/or shown in the attached drawings. The invention further pertains to a method or process comprising one or more of the characterizing features described in the description and/or shown in the attached drawings.

[0177] 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.

[0178] Therefore, amongst others the invention provides in embodiments a luminescent material body, especially having the shape of a tile, a reflective layer attached to part of the luminescent body, an adhesion layer attached to the reflective layer, and a heatsink attached to the adhesion layer, wherein the heatsink is SPD made. Instead of the term “SPD” also the term “SPC”, supersonic powder coating, may be applied.