A light emitting device comprising a 2d array of micro-led light sources

Abstract

A light emitting device for mounting on an external device, the light emitting device being configured to emit device light (2), comprising: a 2D array (3) of micro-LED light sources comprising: a plurality of first micro-LED light sources (6) configured to emit first light (61) having a first peak emission wavelength, wherein each first micro-LED light source comprises a first die (62) having a first surface area with a largest extension less than or equal to 100 μm, a plurality of second micro-LED light sources (7) configured to emit second light (71) having a second peak emission wavelength, wherein each second micro-LED light source comprises a second die (72) having a second surface area with a largest extension less than or equal to 100 μm, and a plurality of third micro-LED light sources (8) configured to emit third micro-LED light source light (81) having a third peak emission wavelength, wherein each third micro-LED light source comprises a third die (82) having a third surface area with a largest extension less than or equal to 100 μm, wherein the first, second, and third peak emission wavelengths mutually differ by at least 15 nm, a common encapsulant (5) covering the 2D array (3), and a lead frame (4) to which the 2D array (3) is mounted, wherein the lead frame (4) is configured to provide the 2D array (3) with an electrical contact (24, 26) and a thermal contact (25) to an external device.

Description

[0001] 2024PF80493

[0002] 1

[0003] A LIGHT EMITTING DEVICE COMPRISING A 2D ARRAY OF MICRO-LED LIGHT SOURCES

[0004] FIELD OF THE INVENTION

[0005] The invention relates to a light emitting device configured to, in operation, emit device light, and comprising a 2D array of micro-LED light sources.

[0006] As used herein, the term “blue light” is intended to refer to light with a peak wavelength falling within the wavelength interval of 420 nm to 500 nm.

[0007] As used herein, the term “green light” is intended to refer to light with a peak wavelength falling within the wavelength interval of 520 nm to 570 nm.

[0008] As used herein, the term “red light” is intended to refer to light with a peak wavelength falling within the wavelength interval of 620 to 750 nm.

[0009] As used herein, the term “micro-LED light source” is intended to refer to LED light sources having a size of less than 100 pm, such as between 50 pm and 100 pm.

[0010] BACKGROUND OF THE INVENTION

[0011] Hitherto, white LED light sources for general illumination have always been based on a blue LED chip covered by a phosphor. Such a white pc-LED has several disadvantages. Using direct-emitting LEDs also has drawbacks.

[0012] A LED package is a type of electronic package that contains a light-emitting diode (LED) and associated components, such as a phosphor layer, electrical contacts, and one or more optical parts such as a reflector and an encapsulant. A LED package is designed to protect the LED from damage and provide a path for electrical connection that makes it suitable for mounting the LED package on different substrates, such as printed circuit boards, PCBs, for different applications.

[0013] US 12,107,204 Bl discloses a micro-LED device and a method of fabricating the micro-LED device. The Micro-LED device is a die or a wafer including a two-dimensional array of micro-LEDs. The micro-LED device includes a CMOS backplane that includes pixel drive circuits formed thereon. The pixel drive circuits are connected to the 2D array of micro-LEDs through metal plugs. The metal plugs include, for example, tungsten or aluminum plugs formed in a dielectric layer (e.g., a SiO2 or SiN) layer. A metal bonding2024PF80493

[0014] 2

[0015] layer is deposited on metal plugs in the CMOS backplane and is bonded to a metal bonding layer on a micro-LED wafer to form a bonded metal layer. The metal bonding layers include, for example, Ni, Ti, TiN, or a combination thereof, and are electrodes for the 2D array of micro-LEDs. Each micro-LED of the 2D array of micro-LEDs further includes a back reflector.

[0016] However, the above-mentioned solutions have several disadvantages, including, but not limited to, limited color rendering, lower efficiency, blue light hazard, and temperature sensitivity.

[0017] SUMMARY OF THE INVENTION

[0018] It is an object of the present invention to overcome this problem, and to provide a light emitting device having one or more of an improved and less limited color rendering, a higher efficiency, an improved safety, particularly a lower blue light hazard, and a lower temperature sensitivity.

[0019] It is a further object of the present invention to provide a light emitting device which is easy to mount on different PCBs or substrates for different applications, and which is capable of providing, in operation, high-quality white or colored light.

[0020] According to a first aspect of the invention, this and other objects are achieved by means of a light emitting device configured to, in operation, emit device light, the light emitting device comprising: a 2D array of micro-LED light sources comprising: a plurality of X first micro-LED light sources configured to emit first micro-LED light source light having a first peak emission wavelength, I, wherein each first micro-LED light source comprises a first die having a first surface area SAI, wherein the first surface area SAI has a first largest spatial extension, SEI, that is less than or equal to 100 micrometers, a plurality of Y second micro-LED light sources configured to emit second micro-LED light source light having a second peak emission wavelength, X2, wherein each second micro-LED light source comprises a second die having a second surface area SA2, wherein the second surface area SA2 has a second largest spatial extension, SE2, that is less than or equal to 100 micrometers, and a plurality of Z third micro-LED light sources configured to emit third micro-LED light source light having a third peak emission wavelength, X3, wherein each third micro-LED light source comprises a third die having a third surface area SA3, wherein the third surface area SA3 has a third largest spatial extension, SE3, that is less than or equal to 100 micrometers, wherein the first peak emission wavelength, I, the second peak emission wavelength, X2, and the third peak emission wavelength, X3, are mutually different by at2024PF80493

[0021] 3

[0022] least 15 nm, wherein the 2D array of the micro-LED light sources comprises N rows of micro-LED light sources and M columns of micro-LED light sources, wherein N > 10 and M > 10, wherein the 2D array of micro-LED light sources comprises a micro-LED light source density of at least 20 % with respect to an area defined as being enclosed by a direct circumference (C) of the 2D array of micro-LED light sources, a common encapsulant covering the 2D array of micro-LED light sources, and a lead frame to which the 2D array of micro-LED light sources is configured to be mounted, wherein, when the light emitting device is mounted on an external device, the lead frame is configured to provide the 2D array of micro-LED light sources with an electrical contact and a thermal contact to the external device.

[0023] Thereby, a light emitting device having one or more of an improved and less limited color rendering, a higher efficiency, an improved safety, particularly a lower blue light hazard, and a lower temperature sensitivity is provided for.

[0024] Such a light emitting device is further easy to mount on different PCBs or substrates for different applications, and further provides, in operation, high-quality white or colored light. The former is due to the lead frame, while the latter is a result of the use of the 2D array of different Micro-LEDs.

[0025] The wording micro-LED density may be defined as the coverage of the plurality of micro-LEDs of the two-dimensional array of a plurality of micro-LEDs as expressed by the ratio of the total surface area of the plurality of micro-LEDs dies to the surface area being enclosed by the outline of the two-dimensional array of a plurality of micro-LEDs.

[0026] Each micro-LED light source has a respective surface area having a respective largest spatial extension, which may also be referred to as a largest dimension, being the largest physical range over which each micro-LED extends.

[0027] The first peak emission wavelength, I, the second peak emission wavelength, X2, and the third peak emission wavelength, X3, may be mutually different by at least 20 nm or at least 25 nm.

[0028] X may be at least 10 or at least 20 or at least 30. Alternatively, or additionally, Y may be at least 10 or at least 20 or at least 30. Alternatively, or additionally, Z may be at least 10 or at least 20 or at least 30.

[0029] The electrical contact and the thermal contact may be provided by the same element or by one element. Alternatively, the electrical contact and the thermal contact may be provided by mutually different elements.2024PF80493

[0030] 4

[0031] The lead frame may further comprise at least one first connection element configured as an electrical contact element for providing the electrical contact, and at least one second connection element configured as heat sink for providing the thermal contact.

[0032] Thereby, a light emitting device is provided which is particularly easy to mount on different PCBs or substrates for different applications.

[0033] The lead frame may comprise a lead frame substrate, wherein the 2D array of micro-LED light sources is arranged on a first major surface of the lead frame substrate, and wherein the at least one first connection element and the at least one second connection element is arranged on a second major surface of the lead frame substrate, the second major surface being opposite to the first major surface, and wherein the lead frame substrate comprises a plurality of vias for providing the electrical contact between the at least on first connection element and the 2D array of micro-LED light sources.

[0034] Thereby, a light emitting device with a very simple structure, especially in terms of the electrical connection to the 2D array of micro-LEDs, is provided for.

[0035] The circumference (C) of the 2D array of micro-LED light sources may comprise a size of less than 5 mm x 5 mm, preferably a size of less than 3 mm x 3 mm, more preferably size of less than 2 mm x 2 mm..

[0036] Thereby, a light emitting device with a very compact structure is provided for. The 2D array of micro-LED light sources may comprise a micro-LED light source density of at least 20 %, or at least 30 %, or at least 40 %, with respect to an area defined as being enclosed by a direct circumference of the 2D array of micro-LED light sources.

[0037] Thereby, a light emitting device capable of providing a very homogenous and uniform device light is provided for.

[0038] The first peak emission wavelength, I, may be in the range of 420 nm to 490 nm.

[0039] The second peak emission wavelength, X2, may be in the range of 500 nm to 590 nm.

[0040] The third peak emission wavelength, X3, may be in the range of 600 nm to 690 nm.

[0041] In an operational mode the device light may be white light having a correlated color temperature in a range of 2000 K and 6500 K, or 2700 - 4500K, and a color rendering index of at least 80, at least 85 or at least 90.2024PF80493

[0042] 5

[0043] The number of first, second and third micro-LED light sources, respectively, may be chosen such that Y > X and Z > X, or such that Y > 2X and / or Z > 2X.

[0044] Thereby, a light emitting device with an improved efficiency and an improved safety is provided for, such a light emitting device further being capable of providing, in operation, high-quality white or colored light.

[0045] One or more of the following may apply: (i) the plurality of X first micro-LED light sources may comprise one or more primary first micro-LED light sources configured to emit primary first micro-LED light source light having a peak emission wavelength, XL, and one or more secondary first micro-LED light sources configured to emit secondary first micro-LED light source light having a peak emission wavelength, XI”, wherein I Xl’-Xl” I > 15 nm, (ii) the plurality of Y second micro-LED light sources may comprise one or more primary second micro-LED light sources configured to emit primary second micro-LED light source light having a peak emission wavelength, X2’, and one or more secondary second micro-LED light sources configured to emit secondary second micro-LED light source light having a peak emission wavelength, X2”, wherein I X2”-X2’ I > 15 nm, or > 20 nm, or > 25 nm, and (iii) the plurality of Z third micro-LED light sources may comprise one or more primary third micro-LED light sources configured to emit primary third micro-LED light source light having a peak emission wavelength, X3’, and one or more secondary third micro-LED light sources configured to emit secondary third micro-LED light source light having a peak emission wavelength, X3”, wherein I X3”-X3’ I > 15 nm, or > 20 nm, or > 25 nm.

[0046] Thereby, a light emitting device having one or more of a further improved and even less limited color rendering, an even higher efficiency, an even more improved safety, particularly a lower blue light hazard, and an even lower temperature sensitivity is provided for. Particularly, if different blue LEDs are provided, the blue light hazard is reduced further.

[0047] The plurality of X first micro-LED light sources may further comprise one or more tertiary first micro-LED light sources configured to emit tertiary first micro-LED light source light having a peak emission wavelength, XL”, wherein XL” XI’ and XL” XI”, or wherein the difference between XL” and XL is at least 15 nm, or at least 20 nm, or at least 25 nm, and the difference between XL” and XI” is at least 15 nm, or at least 20 nm, or at least 25 nm.

[0048] Thereby, the blue light hazard is reduced even further.

[0049] The plurality of Y second micro-LED light sources may further comprise one or more tertiary second micro-LED light sources configured to emit tertiary second micro-2024PF80493

[0050] 6

[0051] LED light source light having a peak emission wavelength, 2’”, wherein 2’, X2” and 2’” mutually differ at least 15 nm.

[0052] The plurality of Z third micro-LED light sources may further comprise one or more tertiary third micro-LED light sources configured to emit tertiary second micro-LED light source light having a peak emission wavelength, X3” ’, wherein 3’, X3” and 3’” mutually differ at least 15 nm.

[0053] The first peak emission wavelength, I, the second peak emission wavelength, 2, and the third peak emission wavelength, 3, may be (i) in the range of 420 nm to 500 nm, or (ii) in the range of 520 nm to 570 nm, or (iii) in the range of 620 nm to 750 nm, and wherein I 2- 1 I > 15 nm, , or > 20 nm, or > 25 nm, I X3-X1 I > 15 nm, or > 20 nm, or > 25 nm, and I X3-X2 I > 15 nm, or > 20 nm, or > 25 nm.

[0054] Thereby, a light emitting device with an improved color rendering is provided for.

[0055] The plurality of X first micro-LED light sources, the plurality of Y second micro-LED light sources, and the plurality of Z, third micro-LED light sources may be arranged in an alternating fashion.

[0056] The plurality of X first micro-LED light sources, the plurality of Y second micro-LED light sources, and the plurality of Z, third micro-LED light sources may be distributed evenly in the 2D array of micro-LED light sources.

[0057] With either of these arrangements it is ensured that the naked eye observes the combined device light as white light without seeing colored effects.

[0058] The device light may comprise: in a first operational mode, first device light being first white light having a first correlated color temperature, CCT1, in a range from 2000 K to 6500 K, or from 1700 K to 6500 K and a first color rendering index, CRI1, of at least 80, and, in a second operational mode, second device light being second white light having a second correlated color temperature, CCT2, in a range from 2000 K to 6500 K, or from 1700 K to 6500 K and a second color rendering index, CRI2, of at least 80, wherein CCT2 > CCT1 + 500 K, or CCT2 > CCT1 + 750 K, or CCT2 > CCT1 + 1000 K.

[0059] The lead frame may comprise a first electrical circuit and a second electrical circuit, and wherein the 2D array (3) of micro-LED light sources is arranged such that at least two micro-LED light source strings are formed powered by the first electrical circuit and the second electrical circuit respectively.

[0060] Thereby, it becomes possible to individually control each string, and thus different subsets, of Micro-LEDs in the 2D array of Micro-LEDs when using a controller.2024PF80493

[0061] 7

[0062] The light emitting device may further comprise a reflector.

[0063] The light emitting device may further comprise an encapsulant, such as a dome-shaped encapsulant.

[0064] Providing a reflector and / or a dome-shaped encapsulant enables optimized light extraction from the light emitting device.

[0065] The light emitting device may further comprise at least one electrical component configured to provide reverse polarity protection.

[0066] The at least one electrical component configured to provide reverse polarity protection may be a Zener-diode.

[0067] Thereby, each micro-LED in the 2D array of micro-LEDs, or in a string of micro-LEDs of the 2D array of micro-LEDs, is protected from surge voltages and overvoltages which may otherwise harm the micro-LED light sources.

[0068] The invention further relates to a light emitting arrangement comprising a light emitting device according to the invention.

[0069] The light emitting arrangement may further comprise the external device. The light emitting arrangement, or the light emitting device, may further comprise a controller configured to individually control the plurality of X first micro-LED light sources, the plurality of Y second micro-LED light sources, and the plurality of Z third micro-LED light sources.

[0070] The light emitting arrangement, or the light emitting device, may further comprise at least one sensor for directly or indirectly sensing at least one characteristic of one or more of the plurality of X first micro-LED light sources, the plurality of Y second micro-LED light sources, and the plurality of Z third micro-LED light sources, and wherein the controller further is configured to receive a signal from the sensor, and to individually control the plurality of X first micro-LED light sources, the plurality of Y second micro-LED light sources, and the plurality of Z third micro-LED light sources based on the signal received from the sensor.

[0071] The external device may further comprise a substrate, wherein the light emitting arrangement comprises at least two light emitting devices according to the invention, wherein the substrate comprises at least two substrate connection elements, and wherein each of the at least two light emitting devices is connected to the substrate via the respective first connection element and the respective second connection element.

[0072] The light emitting arrangement may further comprise at least one electrical component configured to provide reverse polarity protection.2024PF80493

[0073] 8

[0074] The light emitting arrangement, may further comprise a reflector.

[0075] The light emitting device and the light emitting arrangement, may further comprise a common encapsulant.

[0076] The common encapsulant may be dome shaped.

[0077] The invention further relates to a lamp comprising a light emitting device or a light emitting arrangement according to the invention.

[0078] The lamp may further comprise a light transmissive envelope at least partly enclosing the light emitting device and / or a base for electrically and mechanically connecting the lamp to a socket or a socket of a luminaire.

[0079] The invention further relates to a luminaire comprising a light emitting device or a light emitting arrangement according to the invention.

[0080] The invention still further relates to a luminaire comprising a lamp according to the invention. The luminaire may comprise a light exit window and / or a luminaire housing.

[0081] It is noted that the invention relates to all possible combinations of features recited in the claims.

[0082] BRIEF DESCRIPTION OF THE DRAWINGS

[0083] This and other aspects of the present invention will now be described in more detail, with reference to the appended drawings showing embodiment(s) of the invention.

[0084] Fig. 1 shows a cross-sectional side view of a light emitting device according to the invention.

[0085] Fig. 2 shows a top view of the light emitting device according to Fig. 1.

[0086] Fig. 3 shows a cross-sectional side view of another light emitting device according to the invention.

[0087] Fig. 4 shows a top view of the light emitting device according to Fig. 3.

[0088] Fig. 5 shows a cross-sectional side view of another light emitting device according to the invention.

[0089] Fig. 6 shows a top view of the light emitting device according to Fig. 5.

[0090] Fig. 7 shows a circuit diagram illustrating the electrical and mechanical connections of a light emitting device arrangement comprising a plurality of light emitting devices according to the invention.

[0091] Fig. 8 shows a cross-sectional side view of a light emitting device arrangement comprising a plurality of light emitting devices according to the invention.2024PF80493

[0092] 9

[0093] Fig. 9 shows a cross-sectional side view of another light emitting device arrangement comprising a plurality of light emitting devices according to the invention.

[0094] Fig. 10 shows a schematical side view of a lamp comprising a light emitting device or a light emitting device arrangement according to the invention.

[0095] Fig. 11 shows a schematical side view of a luminaire comprising a lamp and a light emitting device or a light emitting device arrangement according to the invention.

[0096] As illustrated in the figures, the sizes of layers and regions are exaggerated for illustrative purposes and, thus, are provided to illustrate the general structures of embodiments of the present invention. Like reference numerals refer to like elements throughout.

[0097] DETAILED DESCRIPTION

[0098] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which currently preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided for thoroughness and completeness, and fully convey the scope of the invention to the skilled person.

[0099] Fig. 1 shows a cross-sectional side view of a light emitting device 1 according to the invention, and Fig. 2 shows a top view of the light emitting device 1.

[0100] Generally, and irrespective of the embodiment, the light emitting device 1 comprises a 2D array 3 of micro-LED light sources 6, 7, 8, a lead frame 4, and an encapsulant 5. The light emitting device 1 is configured to, in operation, emit device light 2.

[0101] The 2D array 3 of micro-LED light sources 6, 7, 8 comprises one or more, particularly a plurality of X, first micro-LED light sources 6. The plurality of X first micro-LED light sources 6 are configured to emit first micro-LED light source light 61. The first micro-LED light source light 61 has a first peak emission wavelength, XL The 2D array 3 of micro-LED light sources 6, 7, 8 further comprises one or more, particularly a plurality of Y, second micro-LED light sources 7. The plurality of Y second micro-LED light sources 7 are configured to emit second micro-LED light source light 71. The second micro-LED light source light 71 has a second peak emission wavelength, X2. The 2D array 3 of micro-LED light sources 6, 7, 8 further comprises one or more, particularly a plurality of Z, third micro-LED light sources 8. The plurality of Z third micro-LED light sources 8 are configured to emit third micro-LED light source light 81. The third micro-LED light source light 81 has a2024PF80493

[0102] 10

[0103] third peak emission wavelength, X3. The first peak emission wavelength, I, the second peak emission wavelength, X2, and the third peak emission wavelength, X3, are mutually different, particularly by at least 15 nm.

[0104] For instance, the first peak emission wavelength, I, may be in the range of 420 nm to 490 nm, or 420 nm to 500 nm, the second peak emission wavelength, X2, may be in the range of 500 nm to 590 nm, or 520 nm to 570 nm, and the third peak emission wavelength, X3, may be in the range of 600 nm to 690 nm, or 620 nm to 750 nm. For instance, and particularly in such a case, it may apply that Y > X and Z > X, or that Y > 2X and Z > X , or that Y > X and Z > 2X, or that Y > 2X and Z > 2X.

[0105] For instance, the first peak emission wavelength, XI, the second peak emission wavelength, X2, and the third peak emission wavelength, X3, may all be (i) in the range of 420 nm to 500 nm, or (ii) in the range of 520 nm to 570 nm, or (iii) in the range of 620 nm to 750 nm. For instance, and particularly in such a case, it may alternatively, or additionally, apply that I X2-X1 I > 15 nm, I X3-X1 I > 15 nm and I X3-X2 I > 15 nm.

[0106] The one or more first micro-LED light sources 6, the one or more second micro-LED light sources 7, and the one or more third micro-LED light sources 8 may be arranged in an alternating fashion. Alternatively, the one or more first micro-LED light sources 6, the one or more second micro-LED light sources 7, and the one or more third micro-LED light sources 8 may be distributed evenly in the 2D array 3 of micro-LED light sources 6, 7, 8.

[0107] Each first micro-LED light source of the plurality of X first micro-LED light sources 6 comprises a first die 62 having a first surface area SAL The first surface area SAI has a first largest spatial extension SEI that is less than or equal to 100 micrometers. Each second micro-LED light source of the plurality of Y second micro-LED light sources 7 comprises a second die 72 having a second surface area SA2. The second surface area SA2 has a second largest spatial extension SE2 that is less than or equal to 100 micrometers. Further, each third micro-LED light source of the plurality of Z third micro-LED light sources 8 comprises a third die 82 having a third surface area SA3. The third surface area SA3 has a third largest spatial extension SE3 that is less than or equal to 100 micrometers.

[0108] The 2D array 3 of micro-LED light sources 6, 7, 8 is configured to be or is mounted on the lead frame 4. The lead frame 4 may be a metal-based lead frame 4. The lead frame 4 is configured to provide the 2D array 3 of micro-LED light sources 6, 7, 8 with an electrical contact and a thermal contact to an external device 29 when the light emitting device 1 is mounted on the external device 29. The light emitting device, or light emitting2024PF80493

[0109] 11

[0110] devices, 1, 100, 101 may be connected to the external device 29 via one or more solders. The lead frame 4 comprises at least one, in the embodiment shown in Fig. 1 two, first connection elements 24, 26. The first connection elements 24, 26 are configured as an electrical contact element. The lead frame 4 further comprises at least one second connection element 25. The second connection element 25 is configured as a heat sink for leading heat away from the 2D array 3 of micro-LED light sources 6, 7, 8. When the light emitting device 1 is mounted on an external device 29 (cf. Figs. 8 and 9), the lead frame 4 is configured to provide the 2D array 3 of micro-LED light sources with an electrical contact and a thermal contact to the external device 29.

[0111] The lead frame 4 comprises a lead frame substrate 41. The lead frame substrate 41 comprises a first major surface 42 and a second major surface 43 opposite to the first major surface 42. The 2D array of micro-LED light sources 3 is arranged on the first major surface 42 of the lead frame substrate 41. The at least one first connection element 24, 26 and the at least one second connection element 25 is arranged on the second major surface 43 of the lead frame substrate 41. The lead frame substrate 41 further comprises a plurality of vias 44. The vias 44 are configured to providing the electrical contact between the at least one first connection element 24, 26 and the 2D array of micro-LED light sources 3.

[0112] The 2D array 3 of micro-LED light sources 6, 7, 8 comprises N rows of micro-LED light sources and M columns of micro-LED light sources. N and M may be chosen such that N > 5 and M > 5, preferably such that N > 10 and M > 10, most preferably such that N > 15 and M > 15. The 2D array 3 of micro-LED light sources 6, 7, 8 comprises a width, W, and a length, L, cf. Fig. 2. The 2D array 3 of micro-LED light sources 6, 7, 8 further comprises an area or size A defined as W*L. The size A of the 2D array 3 of micro-LED light sources 6, 7, 8 may be less than 3 mm x 3 mm. The 2D array 3 of micro-LED light sources 6, 7, 8 also comprises a micro-LED light source density. The micro-LED light source density may be at least 20 %, or at least 30 %, or at least 40 %. The micro-LED light source density may be measured with respect to an area defined as being enclosed by a direct circumference, C, of the 2D array 2 of Micro-LED light sources 6, 7, 8, cf. Fig. 2. The direct circumference, C, may be defined as C = 2*L + 2*W.

[0113] The encapsulant 5 is one common encapsulant 5. The encapsulant 5 covers the 2D array of micro-light sources. The encapsulant 5 may be a transparent or translucent encapsulant. Alternatively, the encapsulant 5 may comprise one or more optical characteristics, such as being diffusive. The encapsulant 5 may be dome shaped.2024PF80493

[0114] 12

[0115] The light emitting device 1 further comprises at least one optional reflector 22. The reflector 22 may be a reflective layer or coating or element arranged on a surface of the encapsulant 5. The reflector 22 is configured to reflect one or more of the first micro-LED light source light 61, the second micro-LED light source light 71 and the third micro-LED light source light 81 in a direction away from the array 3 of micro-LED light sources 6, 7, 8.

[0116] The device light 2 may, in a first operational mode, comprise first device light being first white light having a first correlated color temperature, CCT1, in a range from 2000 K to 6500 K and, optionally, a first color rendering index, CRI1, of at least 80.

[0117] Alternatively, or additionally, the device light 2 may, in a second operational mode, comprise second device light being second white light having a second correlated color temperature, CCT2, in a range from 2000 K to 6500 K and, optionally, a second color rendering index, CR.I2, of at least 80. In case of the device light 2 comprising both first and second device light, it may apply that CCT2 > CCT1 + 500 K.

[0118] Fig. 3 shows a cross-sectional side view of another light emitting device 100 according to the invention, and Fig. 4 shows a top view of the light emitting device 100. The light emitting device 100 differs from the light emitting device 1 shown in Figs. 1 and 2 and described above in virtue of the following features.

[0119] The plurality of Y second micro-LED light sources 7 comprises one or more primary second micro-LED light sources 7’ and one or more secondary second micro-LED light sources 7”. The one or more primary second micro-LED light sources 7’ are configured to emit primary second micro-LED light source light 71’. The primary second micro-LED light source light 71’ has a peak emission wavelength, 2’. The one or more secondary second micro-LED light sources 7” are configured to emit secondary second micro-LED light source light 71”. The secondary second micro-LED light source light 71” has a peak emission wavelength, 2”. The peak emission wavelengths 2’ and X2” are chosen such that I X2”-X2’ I > 15 nm, or I X2”-X2’ I > 20 nm.

[0120] Furthermore, the plurality of Z third micro-LED light sources 8 comprises one or more primary third micro-LED light sources 8’ and one or more secondary third micro-LED light sources 8”. The one or more primary third micro-LED light sources 8’ are configured to emit primary third micro-LED light source light 81’. The primary third micro-LED light source light 81’ has a peak emission wavelength, 3’. The one or more secondary third micro-LED light sources 8” are configured to emit secondary third micro-LED light source light 81”. The secondary third micro-LED light source light 81” has a peak emission2024PF80493

[0121] 13

[0122] wavelength, X3”. The peak emission wavelengths X3’ and X3” are chosen such that | X3”-X3’ I > 15 nm, or I X3”-X3’ I > 20 nm.

[0123] Still further, the plurality of X first micro-LED light sources 6 comprises one or more primary first micro-LED light sources 6’ and one or more secondary first micro-LED light sources 6”. The one or more primary first micro-LED light sources 6’ are configured to emit primary first micro-LED light source light 61’. The primary first micro-LED light source light 6’ has a peak emission wavelength, XL. The one or more secondary first micro-LED light sources 6” are configured to emit secondary first micro-LED light source light 61”. The secondary first micro-LED light source light 61” has a peak emission wavelength, XI”. The peak emission wavelengths XL and XI” are chosen such that I Xl’-Xl” I > 15 nm, or I Xl’-Xl” I > 20 nm.

[0124] It is noted that embodiments in which only one or two of the above-mentioned three options applies are also feasible.

[0125] The plurality of X first micro-LED light sources 6 further optionally comprises one or more optional tertiary first micro-LED light sources 6’”. The one or more tertiary first micro-LED light sources 6’” are configured to emit tertiary first micro-LED light source light 61’”. The tertiary first micro-LED light source light 61’” has a peak emission wavelength, XL”. The peak emission wavelength XL” may be chosen such that the difference between XL” and XL is at least 15 nm and the difference between XL” and XI” is at least 15 nm. Alternatively, the peak emission wavelength XL” may be chosen such that XL” X1’ and XI’” X1”.

[0126] The plurality of Y second micro-LED light sources 7 further optionally comprises one or more optional tertiary second micro-LED light sources 7’”. The one or more tertiary second micro-LED light sources 7’” are configured to emit tertiary second micro-LED light source light 71’”. The tertiary second micro-LED light source light 71’” has a peak emission wavelength, X2’”. The peak emission wavelength, X2’” may be chosen such that X2’, X2” and X2’” are mutually different by at least 15 nm.

[0127] The plurality of Z third micro-LED light sources 8 further optionally comprises one or more optional tertiary third micro-LED light sources 8’”. The one or more tertiary third micro-LED light sources 8’” are configured to emit tertiary second micro-LED light source light 81’”. The tertiary second micro-LED light source light 81’” has a peak emission wavelength, X3’”. The peak emission wavelength, X3’” may be chosen such that X3’, X3” and X3’” are mutually different by at least 15 nm.2024PF80493

[0128] 14

[0129] Fig. 5 shows a cross-sectional side view of another light emitting device 101 according to the invention, and Fig. 6 shows a top view of the light emitting device 101. The light emitting device 101 differs from the light emitting device 1 shown in Figs. 1 and 2 and described above in virtue of the following features.

[0130] The 2D array 3 of micro-LED light sources 6, 7, 8 comprises a plurality of X first micro-LED light sources 6, a plurality of Y second micro-LED light sources 7, and a plurality of Z third micro-LED light sources 8.

[0131] In this case, however, the first peak emission wavelength, I, the second peak emission wavelength, X2, and the third peak emission wavelength, X3, are chosen such as to all be (i) in the range of 420 nm to 500 nm, or (ii) in the range of 520 nm to 570 nm, or (iii) in the range of 620 nm to 750 nm.

[0132] In either case, the first peak emission wavelength, I, the second peak emission wavelength, X2, and the third peak emission wavelength, X3, are chosen such that I X2-X1 I > 15 nm, I X3-X1 I > 15 nm, and I X3-X2 I > 15 nm, or such that I X2-X1 I > 20 nm, I X3-X1 I > 20 nm, and I X3-X2 I > 20 nm.

[0133] The plurality of X first micro-LED light sources 6, the plurality of Y second micro-LED light sources 7, and the plurality of Z third micro-LED light sources 8 may be arranged in an alternating fashion. Alternatively, the plurality of X first micro-LED light sources 6, the plurality of Y second micro-LED light sources 7, and the plurality of Z third micro-LED light sources 8 may be distributed evenly in the 2D array 3 of micro-LED light sources 6, 7, 8.

[0134] Referring now to Fig. 7, in either of the above light emitting devices 1, 100 and 101, the 2D array 3 of micro-LED light sources 6, 7, 8 may be arranged such that at least two micro-LED light source strings 19, 20, 21, 22 are formed. More particularly, the lead frame 41 comprises a first electrical circuit 28 and an optional second electrical circuit, and wherein the 2D array 3 of micro-LED light sources is arranged such that at least two micro-LED light source strings 19, 20, 21 are formed powered by the first electrical circuit 28 and, where provided, by the second electrical circuit.

[0135] Additionally, or alternatively, the light emitting device 1 further comprises at least one electrical component 17 being configured to provide reverse polarity protection. The at least one electrical component 17 may for instance be a Zener-diode.

[0136] As is shown in Fig. 1 and Fig. 7, the light emitting device 1 further comprises an optional controller 27. The controller 27 is configured to individually control the plurality2024PF80493

[0137] 15

[0138] of X first micro-LED light sources 6, the plurality of Y second micro-LED light sources 7, and the plurality of Z third micro-LED light sources 8 of the 2D array 3 of micro-LED light sources 6, 7, 8. The controller 27 may also be configured to individually control subsets of the micro-LED light sources 6, 7, 8, of the 2D array 3 of micro-LED light sources 6, 7, 8.

[0139] The light emitting device 1 further comprises at least one optional sensor 18. The sensor 18 is configured to directly, or indirectly, sense at least one characteristic of one or more of the plurality of X first micro-LED light sources 6, the plurality of Y second micro-LED light sources 7, and the plurality of Z third micro-LED light sources 8. The at least one characteristic may for instance be the temperature of the micro-LED light sources 6, 7, 8, the CCT of the emitted light, the CRI of the emitted light or the intensity of the emitted light. The controller 27 may then further be configured to receive a signal from the sensor 18, and to individually control the plurality of X first micro-LED light sources 6, the plurality of Y second micro-LED light sources 7, and the plurality of Z third micro-LED light sources 8, or subsets of the plurality of X first micro-LED light sources 6, the plurality of Y second micro-LED light sources 7, and the plurality of Z third micro-LED light sources 8, of the 2D array 3 of micro-LED light sources 6, 7, 8 based on the signal received from the sensor 18.

[0140] Fig. 8 shows a cross-sectional side view of a light emitting device arrangement 200 according to the invention and comprising a plurality of light emitting devices 1, 100, 101 according to the invention. In the embodiment shown in Fig. 8, the light emitting device arrangement 200 comprises three light emitting devices 1.

[0141] Fig. 9 shows a cross-sectional side view of another light emitting device arrangement 201 comprising a plurality of light emitting devices 1, 100, 101 according to the invention. In the embodiment shown in Fig. 9, the light emitting device arrangement 201 comprises two light emitting devices 1.

[0142] In either case, the light emitting device arrangement 200 or 201 comprises a substrate 13. The substrate 13 comprises at least two substrate connection elements 14, 15, 16 (cf. Fig. 8). Each of the light emitting devices 1 is connected to a respective substrate connection element 14, 15, 16 of the substrate connection elements 14, 15, 16. The connection between a light emitting device 1 and the corresponding connection element 14, 15 or 16 may be made via the lead frame 4. Alternatively, the connection between a light emitting device 1 and the corresponding connection element 14, 15 or 16 may be made via the at least one first connection element 24, 26 and the at least one second connection element 25.2024PF80493

[0143] 16

[0144] The light emitting arrangement 200 or 201 may further comprise the external device 29.

[0145] The light emitting arrangement 200 or 201 may further comprise the controller 27 being configured to individually control the plurality of X first micro-LED light sources 6, the plurality of Y second micro-LED light sources 7, and the plurality of Z third micro-LED light sources 8.

[0146] The light emitting arrangement 200 or 201 may further comprise at least one sensor 18 for directly or indirectly sensing at least one characteristic of the micro-LED light sources 6, 7, 8.

[0147] Fig. 10 shows an exemplary lamp 300 comprising a light emitting device 1, 100, 101 according to any embodiment of the invention. In the embodiment shown, the light emitting device 1, 100, 101 comprises a substantially straight light emitting device. The light emitting device of such a lamp may in other embodiments be a light emitting device with another shape, such as, but not limited to, flat. Alternatively, the lamp 300 may comprise a light emitting arrangement 200 or 201 according to any embodiment of the invention.

[0148] The lamp 300 further comprises a driver or controller 305 configured for controlling the plurality of micro-LEDs 6, 7, 8 of the light emitting device 1, 100, 101. The controller 305 is configured to power the plurality of micro-LEDs 6, 7, 8 via electrical circuitry (not visible on the figures) of the light emitting device 1, 100, 101. The light emitting device 1, 100, 101 may also comprise a controller 27, which may or may not be separate from the controller 305. In other words, the controller 305 and the controller 27 of the light emitting device 1, 100, 101 may be integrated into one and the same driver or controller, or they may be mutually separate units.

[0149] The lamp 300 further comprises an envelope 301 at least partially enveloping the at least one light emitting device 1, 100, 101. The lamp 300 further comprises a cap 303. As shown in Fig. 10, the controller 305 is arranged within the envelope 301. When comprising a cap 303, the controller 305 may also be arranged inside the cap 303 such that it is hidden from view. The lamp 300 further comprises threading 302 for connection to a socket, and a terminal 304 for connection to a source of electrical energy.

[0150] The envelope 301 of the lamp 300 may further and optionally be provided with a coating (not shown), such as a reflective coating, covering at least a part of the envelope 301.

[0151] Turning finally to Fig. 11, an exemplary luminaire in the form of a pendant 400 is shown. The pendant 400 comprises a light emitting device 1, 100, 101 according to2024PF80493

[0152] 17

[0153] any embodiment of the invention. Alternatively, the pendant 400 may comprise a light emitting arrangement 200 or 201 according to any embodiment of the invention.

[0154] The light emitting device 1, 100, 101 is as shown in Fig. 11 provided within a lamp 300 in the form of a light bulb. The light emitting device 1, 100,101 as shown in Fig. 11 comprises a substantially straight light emitting device.

[0155] As is also mentioned above, the light bulb further comprises a transparent envelope (cf. transparent envelope 301 of lamp 300) at least partially enveloping the at least one light emitting device 1, 100, 101. The transparent envelope may be shaped in any feasible shape, for example such as to resemble the shape of any one of a standard light bulb, a globe light bulb, a candlelight bulb, a customized light bulb and even a spiral light bulb. The transparent envelope may comprise a luminescent material. The transparent envelope may be a glass envelope.

[0156] The pendant 400 further comprises a socket 401 for connecting the lamp 300, and thereby the light emitting device 1, 100, 101, to the pendant 400. The socket 401 is adapted to cooperate with the base 303 of the lamp 300. The socket 401 may comprise a threading adapted to cooperate with the threading 302 of the lamp 300. The socket 401 may comprise a terminal adapted to cooperate with the terminal 304 of the lamp 300. The pendant 400 further comprises a reflector or screen 403.

[0157] The pendant 400 may further comprise a driver 402 configured for controlling the light emitting device 1, 100, 101. The driver 402 may or may not be the same unit as the controller 305 described above. In other words, the driver 402 and the controller 305 may be integrated into one and the same driver or controller, or they may be mutually separate units. Alternatively, or additionally, the light emitting device 1, 100, 101 may also comprise a controller 27, which may or may not be separate from one or both of the driver 402 and the controller 305.

[0158] As shown in Fig. 11, the driver 402 is arranged on a reflector or screen 403 of the pendant 400. The driver may also be arranged within or incorporated into the reflector or screen 403. The pendant 400 further comprises an electrical wiring 404 for connection to a source of electricity, such as a mains.

[0159] It is noted that the pendant 400 shown in Fig. 11 is only one example of a luminaire according to the invention. Any suitable type of luminaire may be envisaged, such as but not limited to, a standing luminaire, a wall hung luminaire, a chandelier, a reading luminaire, an outdoor luminaire, and a table luminaire.2024PF80493

[0160] 18

[0161] The person skilled in the art realizes that the present invention by no means is limited to the preferred embodiments described above. On the contrary, many modifications and variations are possible within the scope of the appended claims.

[0162] Additionally, variations to the disclosed embodiments can be understood and effected by the skilled person in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage.

Claims

2024PF8049319CLAIMS:

1. A light emitting device (1) for mounting on an external device, the light emitting device (1) being configured to, in operation, emit device light (2), the light emitting device comprising:(i) a 2D array (3) of micro-LED light sources comprising:a plurality of X first micro-LED light sources (6) configured to emit first micro-LED light source light (61) having a first peak emission wavelength, I, wherein each first micro-LED light source comprises a first die (62) having a first surface area SAI, wherein the first surface area SAI has a first largest spatial extension, SEI, that is less than or equal to 100 micrometers,a plurality of Y second micro-LED light sources (7) configured to emit second micro-LED light source light (71) having a second peak emission wavelength, X2, wherein each second micro-LED light source comprises a second die (72) having a second surface area SA2, wherein the second surface area SA2 has a second largest spatial extension, SE2, that is less than or equal to 100 micrometers, anda plurality of Z third micro-LED light sources (8) configured to emit third micro-LED light source light (81) having a third peak emission wavelength, X3, wherein each third micro-LED light source comprises a third die (82) having a third surface area SA3, wherein the third surface area SA3 has a third largest spatial extension, SE3, that is less than or equal to 100 micrometers,wherein the 2D array of the micro-LED light sources comprises N rows of micro-LED light sources and M columns of micro-LED light sources, wherein N > 10 and M > io,wherein the 2D array of micro-LED light sources comprises a micro-LED light source density of at least 20 % with respect to an area defined as being enclosed by a direct circumference (C) of the 2D array of micro-LED light sources;wherein the first peak emission wavelength, I, the second peak emission wavelength, X2, and the third peak emission wavelength, X3, are mutually different by at least 15 nm;2024PF8049320(ii) a common encapsulant (5) covering the 2D array of micro-LED light sources; and(iii) a lead frame (4) to which the 2D array of micro-LED light sources is mounted, wherein, when the light emitting device is mounted on the external device, the lead frame (4) is configured to provide the 2D array of micro-LED light sources with an electrical contact and a thermal contact to the external device.

2. The light emitting device according to claim 1, wherein the lead frame (4) further comprises:at least one first connection element (24, 26) configured as an electrical contact element for providing the electrical contact, andat least one second connection element (25) configured as heat sink for providing the thermal contact.

3. The light emitting device according to claim 2, wherein the lead frame (4) comprises a lead frame substrate (41), wherein the 2D array of micro-LED light sources (3) is arranged on a first major surface (42) of the lead frame substrate, and wherein the at least one first connection element (24, 26) and the at least one second connection element (25) is arranged on a second major surface (43) of the lead frame substrate opposite to the first major surface, and wherein the lead frame substrate (41) comprises a plurality of vias (44) for providing the electrical contact between the at least one first connection element (24, 26) and the 2D array of micro-LED light sources (3).

4. The light emitting device according to any one of the above claims, wherein the following applies:the direct circumference (C) of the 2D array (3) of micro-LED light sources comprises a size of less than 3 mm x 3 mm, andthe 2D array (3) of micro-LED light sources comprises a micro-LED light source density of at least 40 % with respect to an area defined as being enclosed by the direct circumference (C) of the 2D array (3) of micro-LED light sources.

5. The light emitting device according to any one of the above claims, wherein:the first peak emission wavelength, I, is in the range of 420 nm to 490 nm,2024PF8049321the second peak emission wavelength, X2, is in the range of 500 nm to 590 nm, andthe third peak emission wavelength, X3, is in the range of 600 nm to 690 nm, and wherein in an operational mode the device light is white light having a correlated color temperature in a range of 2000 K to 6500 K, and a color rendering index of at least 80, whereinY > X and Z > X.

6. The light emitting device according to claim 5, wherein two or more of the following apply:the plurality of X first micro-LED light sources (6) comprises one or more primary first micro-LED light sources (6’) configured to emit primary first micro-LED light source light (61’) having a peak emission wavelength, XL, and one or more secondary first micro-LED light sources (6”) configured to emit secondary first micro-LED light source light (61”) having a peak emission wavelength, XI”, wherein I Xl’-Xl” I > 15 nm,the plurality of Y second micro-LED light sources (7) comprises one or more primary second micro-LED light sources (7’) configured to emit primary second micro-LED light source light (71’) having a peak emission wavelength, X2’, and one or more secondary second micro-LED light sources (7”) configured to emit secondary second micro-LED light source light (71”) having a peak emission wavelength, X2”, wherein I X2”-X2’ I > 15 nm, andthe plurality of Z third micro-LED light sources (8) comprises one or more primary third micro-LED light sources (8’) configured to emit primary third micro-LED light source light (81’) having a peak emission wavelength, X3’, and one or more secondary third micro-LED light sources (8”) configured to emit secondary third micro-LED light source light (81”) having a peak emission wavelength, X3”, wherein I X3”-X3’ I > 15 nm.

7. The light emitting device according to any one of claims 1 to 5, wherein one or more of the following applies:(i) the plurality of X first micro-LED light sources (6) comprises one or more primary first micro-LED light sources (6’) configured to emit primary first micro-LED light source light (61’) having a peak emission wavelength, XL, and one or more secondary first micro-LED light sources (6”) configured to emit secondary first micro-LED light source2024PF8049322light (61”) having a peak emission wavelength, XI”, and one or more tertiary first microLED light sources (6”’) configured to emit tertiary first micro-LED light source light (61”’) having a peak emission wavelength, XI’”, wherein XT, XI” and XI’” mutually differ at least 15 nm,(ii) the plurality of Y second micro-LED light sources (7) comprises one or more primary second micro-LED light sources (7’) configured to emit primary second micro-LED light source light (71’) having a peak emission wavelength, X2’, and one or more secondary second micro-LED light sources (7”) configured to emit secondary second micro-LED light source light (71”) having a peak emission wavelength, X2”, and one or more tertiary second micro-LED light sources (7’”) configured to emit tertiary second micro-LED light source light (71’”) having a peak emission wavelength, X2’”, wherein X2’, X2” and X2’” mutually differ at least 15 nm, and(iii) the plurality of Z third micro-LED light sources (8) comprises one or more primary third micro-LED light sources (8’) configured to emit primary third micro-LED light source light (81’) having a peak emission wavelength, X3’, and one or more secondary third micro-LED light sources (8”) configured to emit secondary third micro-LED light source light (81”) having a peak emission wavelength, X3”, and one or more tertiary third micro-LED light sources (8’”) configured to emit tertiary second micro-LED light source light (81’”) having a peak emission wavelength, X3’”, wherein X3’, X3” and X3’” mutually differ at least 15 nm.

8. The light emitting device according to any one of claims 1 to 4, wherein the first peak emission wavelength, XI, the second peak emission wavelength, X2, and the third peak emission wavelength, X3, all are (i) in the range of 420 nm to 500 nm, or (ii) in the range of 520 nm to 570 nm, or (iii) in the range of 620 nm to 750 nm, and wherein I X2-X1 I > 15 nm, I X3-X1 I > 15 nm and I X3-X2 I > 15 nm.

9. The light emitting device according to any one of the above claims, wherein the plurality of X first micro-LED light sources (6), the plurality of Y second micro-LED light sources (7), and the plurality of Z third micro-LED light sources (8) are arranged in an alternating fashion.2024PF804932310. The light emitting device according to any one of the above claims, wherein the device light (2) comprises:in a first operational mode, first device light being first white light having a first correlated color temperature, CCT1, in a range from 2000K to 6500K and a first color rendering index, CRI1, of at least 80, andin a second operational mode, second device light being second white light having a second correlated color temperature, CCT2, in a range from 2000K to 6500K and a second color rendering index, CRI2, of at least 80, whereinCCT2 > CCT1 + 500K.

11. The light emitting device according to any one of the above claims, wherein the lead frame comprises a first electrical circuit (28) and a second electrical circuit, and wherein the 2D array (3) of micro-LED light sources is arranged such that at least two microLED light source strings (19, 20, 21) are formed powered by the first electrical circuit (28) and the second electrical circuit, respectively.

12. A light emitting arrangement (200, 201) comprising the light emitting device (1) according to any one of the above claims, and further comprising the external device (29) and a controller (27) configured to individually control the plurality of X first micro-LED light sources (6), the plurality of Y second micro-LED light sources (7), and the plurality of Z third micro-LED light sources (8).

13. The light emitting arrangement according to claim 12, wherein the light emitting device (1) further comprises at least one sensor (18) for directly or indirectly sensing at least one characteristic of one or more of the plurality of X first micro-LED light sources (6), the plurality of Y second micro-LED light sources (7), and the plurality of Z third micro-LED light sources (8), and whereinthe controller (27) further is configured to receive a signal from the sensor (18), and to individually control the plurality of X first micro-LED light sources (6), the plurality of Y second micro-LED light sources (7), and the plurality of Z third micro-LED light sources (8) based on the signal received from the sensor (18).

14. The light emitting arrangement according to claim 12 or 13, wherein the external device comprises a substrate (13), and wherein the light emitting arrangement2024PF8049324comprises at least two light emitting devices (1) according to any one of claims 2-11, wherein the substrate (13) comprises at least two substrate connection elements (14, 15, 16), and wherein each of the at least two light emitting devices (1) is connected to the substrate (13) via the respective first connection element (24, 26) and the respective second connection element (25).

15. A lamp or a luminaire comprising the light emitting device (1) according to any one of claims 1-11 or the light emitting device arrangement according to any one of claims 12-14.

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