LED array comprising normal-sized LEDS and micro leds

Abstract

The present invention relates to a lighting device (100) configured to provide device light, the lighting device comprising a carrier (113), a first white LED light source (105) to provide first white LED light and a second white LED light source (106) to provide second white LED light, arranged on the carrier (113). The first white LED light source (105) comprises at least one first light emitting diode, N-LED (101), the N-LED (101) comprising a die having a first surface area, SA1, wherein the SA1 has a largest spatial extent, SE1, that is greater than or equal to 300 micrometers. The second white LED light source (106) comprises a plurality of second light emitting diodes, M-LEDs (102), each of the M-LEDs (102) comprising a die having a second surface area, SA2, wherein the SA2 has a largest spatial extent, SE2, that is less than or equal to 100 micrometers. The ratio R1, is defined by SA1 / SA2 and is equal to or larger than 10. The plurality of M-LEDs (102) is arranged in a group of M-LEDs and confined within an area, A, and the at least one N-LED (101) is arranged outside the area A. The first white LED light has a first correlated color temperature, CCT1, in a range from 2000K to 6500K; and optionally having a color render index, CRI1, of at least 70. The second white LED light has a second correlated color temperature, CCT2, in a range from 2000K to 6500K; and optionally having a color render index, CRI2, of at least 70. In an operational mode of the lighting device the device light comprises the first LED light and the second LED light. The at least one first light emitting diode, N-LED (101), is covered by a first optical structure (107) configured to collimate the first white LED light; and the plurality of second light emitting diodes, M-LEDs (102), is covered by a second optical structure (108) and configured to collimate the second white LED light.

Description

[0001] 2024PF80107

[0002] 1

[0003] LED ARRAY COMPRISING NORMAL-SIZED LEDS AND MICRO LEDS

[0004] FIELD OF THE INVENTION

[0005] The present disclosure generally relates to the field of LED lighting devices, in particular to a lighting device combining normal-sized LEDs and micro-sized LEDs for homogenous white LED light.

[0006] BACKGROUND OF THE INVENTION

[0007] MicroLEDs have been developed for the electronic display industry but are recently also being applied in lighting applications such as headlamps. In such a use, MicroLEDs offer advantages due to their high efficiency, long lifespan, and great environmental tolerance. However, MicroLEDs are still rather expensive, show color over angle variation and have limited brightness.

[0008] Therefore, there is a need to provide an alternative light source in particular for use as a headlamp which at least partly obviates one or more of above-described drawbacks.

[0009] US 2013 / 270581 discloses light emitter packages having multiple light emitter chips, such as LED chips. In one aspect, a light emitter package can include a submount, an array of light emitter chips disposed on a portion of the submount, and a lens provided over the submount and covering at least portions of the array. In some aspects, at least some of the light emitter chips can be adapted to emit light of a first dominant wavelength. In further aspects, at least some other light emitter chips are adapted to emit light of a second dominant wavelength that is different than the first dominant wavelength. In some aspects, the lens can be asymmetric. In some aspects, a collective center of the chips, or a center of an array of chips can be offset from a center of the asymmetric lens.

[0010] SUMMARY OF THE INVENTION

[0011] It is therefore an object of the present invention to overcome at least some of the above-mentioned drawbacks, and to provide an improved lighting device in particular for use as a headlamp. This and other objects are achieved by means of a lighting device as defined in the appended independent claim(s). Other embodiments are defined by the dependent claims. It is noted that other embodiments using all possible combinations of 2024PF80107

[0012] 2 features recited in the above-described embodiments may be envisaged. Thus, the present disclosure also relates to all possible combinations of features mentioned herein.

[0013] To this end, the present invention provides a lighting device configured to provide device light. The lighting device comprises a carrier, a first white LED light source, and a second white LED light source. The first and second white LED light source are arranged on the first major surface of the carrier. The first white LED light source is configured to provide first white LED light and the second LED light source is configured to provide second white LED light.

[0014] The first white LED light source comprises at least one first light emitting diode, N-LED. The at least one N-LED is a normal-sized LED and comprises a die having a first surface area, SAL SAI has a largest spatial extent, SEI, that is greater than or equal to 300 micrometers. The N-LED may be any type of LED able to provide white light.

[0015] The second white LED light source comprises a plurality of X second light emitting diodes, M-LEDs. The M-LEDs are micrometer-sized LEDs and each of the M-LEDs comprises a die having a second surface area, SA2. SA2 has a largest spatial extent, SE2, that is less than or equal to 100 micrometers. It should be noted that the size above relates to the size of the LED chip.

[0016] Further, a ratio Rl, defined by SA1 / SA2, is equal to or larger than 10. R1 defines that the size of the N-LED die and the size of the M-LED die may not deviate such that Rl is less than 10.

[0017] The plurality of M-LEDs is arranged in a group of M-LEDs and confined within an area, A, and the at least one N-LED is arranged outside the area A.

[0018] The first white LED light has a first correlated color temperature, CCT1, in a range from 2000K to 6500K. Optionally, the first LED light has a color render index, CRI1, of at least 70 or at least 80.

[0019] The second white LED light has a second correlated color temperature, CCT2, in a range from 2000K to 6500K. Optionally, the second LED light has a color render index, CR.I2, of at least 70 or at least 80.

[0020] The at least one first light emitting diode, N-LED, is covered by a first optical structure. The first optical structure is configured to collimate the first white LED light. The plurality of second light emitting diodes, M-LEDs, is covered by a second optical structure. The second optical structure is configured to collimate the second white LED light.

[0021] The first and / or second optical structures may for example be a (projector) lens or a plurality of lenses. 2024PF80107

[0022] 3

[0023] By the term “die” it is understood to mean a LED chip or the epitaxial area. Thus, the surface area of the complete LED package may be greater than the surface area of a LED chip or die.

[0024] By the term “collimate” it is understood as to narrow or decrease the spatial light distribution e.g. full-width-half-max of the first and / or second device light.

[0025] Since the N-LED have a spatial extent SEI that is greater than or equal to 300 micrometers, and the M-LED have a spatial extent SE2 that is less than or equal to 100 micrometers, the first white LED light source provides a low-resolution pattern and the second white LED light provides a high-resolution pattern.

[0026] The first optical structure collimates the first white LED light emitted by the white LED light source such that a first illumination pattern is provided. Further, the second optical structure collimates the second white LED light emitted by the second white LED light source such that a second illumination pattern is provided.

[0027] In the lighting device of the present invention, the first and second illumination pattern may be superimposed such to jointly form a main illumination pattern. Thus, the main illumination pattern will have a high intensity and brightness mainly provided by the first illumination pattern and a high resolution mainly provided by the second illumination pattern.

[0028] The size and shape of the first illumination pattern and the second illumination pattern may be varied by the size and shape of the at least one N-LEDs and the plurality of M-LEDs, depending on the desired size and shape of the main illumination pattern. For example, if a circular pattern of the main illumination pattern is desired, the size and shape of the first and second white LED light sources may be chosen thereafter. In another embodiment, a square shaped main illumination pattern may be desired, and thus the size and shape of the first and second white LED light sources may be chosen to achieve the desired square shape. Furthermore, it is to be understood that other geometrical shapes and sizes shall not be excluded as the lighting device of the present invention may be designed in any shape or size contained in the art.

[0029] The color rendering index is a quantitative measure between 0 and 100, which determines the ability of light to reveal its true color. Since the color rendering indices CRI1 and CRI2 of the first LED light and the second LED light are at least 70, the true color of the device light may be easily perceived by the end-user. 2024PF80107

[0030] 4

[0031] In embodiments, the first surface area, SAI, may have a largest spatial extent, SEI, greater than or equal to 400 micrometers, preferably SEl>500 micrometers, more preferably SEl>600 micrometers, most preferably SEl>700 micrometers.

[0032] In embodiments, the second surface area, SA2, may have a largest spatial extent, SE2, less than or equal to 80 micrometers, preferably SE2<70 micrometers, more preferably SE2<60 micrometers, most preferably SE2<50 micrometers.

[0033] In embodiments, the ratio, Rl, defined by SA1 / SA2, may be equal to or larger than 12, preferably Rl may be equal to or larger than 13, more preferably Rl may be equal to or larger than 14, most preferably Rl may be equal to or larger than 15.

[0034] The first correlated color temperature, CCT1, may be equal to the second correlated color temperature, CCT2, such that CCT1=CCT2. Such an embodiment is advantageous because if the first and second white LED light have the same correlated color temperature, the device light emitted by the lighting device may be perceived as more homogenous by the end-user.

[0035] Alternatively, in embodiments CCT1 may be different from CCT2 e.g.

[0036] The term “correlated color temperature” is a measure of the quality of white light, which describes the proportions of low frequency white visible light and high frequency white visible light. The correlated color temperature is measured in Kelvin. Further, white light having a certain correlated color temperature is white light with a color corresponding to the color of light emitted by a black-body with the same correlated color temperature.

[0037] The lighting device according to the invention may further comprise a controller for individually controlling the first white LED light and second white LED light sources.

[0038] The term “controller” as used herein is intended to mean a device, arrangement, element, or the like, which is configured to control first and second intensities of the light emitted from the first white LED light source and the second white LED light source, respectively. The operation of the controller is performed according to one or more predetermined settings. The term “predetermined setting,” as used herein is intended to mean a setting, setup, program, relationship, or the like, which is set or determined in advance. The controller may hereby control the total color temperature and / or light intensity of the light emitted from the lighting device as a function of this or these predetermined setting(s). 2024PF80107

[0039] 5

[0040] The first optical structure may have a shape and / or size which is different from the shape and / or size of the second optical structure.

[0041] For example, since the area A comprises the plurality of M-LEDs, the size and shape of area A is dependent on the size and the shape of the M-LED and the number of M- LEDs comprised within the plurality of M-LEDs. Therefore, the second optical structure, which is configured to collimate the second white LED light emitted by the second LED light source, is required to be at least as large as the area A, such that all of the M-LEDs in the plurality of M-LEDs may be covered by the second optical structure.

[0042] Further, the at least one N-LED is arranged outside the area A and is independent of the properties of the plurality of M-LEDs. The first optical structure, which is configured to collimate the first white LED light emitted by the first LED light source, is required to be at least large enough to cover the at least one N-LED.

[0043] When the area A and the area covered by the at least one N-LED are not the same, the first optical structure and the second optical structure have different size and / or shape.

[0044] The first optical structure may be of the type being same as or different from the type of the second optical structure. The term “type” used herein, may for example refer to an imaging optical structure or to a non-imaging optical structure. By way of example, the first optical structure may be an imaging optical structure and the second optical structure may be a non-imaging optical structure or the other way around. In such an embodiment, the shape and size of the first and second optical structure may be the same or different.

[0045] The first optical structure and the second optical structure may be selected from the optical structure types of a refractive optical element, a diffractive optical element and a reflective optical element, wherein the first optical structure and the second optical structure may be of different types. By way of example, the first optical structure may be a refractive optical element and the second optical structure may be a diffractive optical element or the other way around, or any of the first optical structure and the second optical structure may be a reflective optical element. In such exemplifying embodiments, the shape and size of the first and second optical structure may be the same or different.

[0046] The first optical structure may be of the same type as the second optical structure, i.e., the first and second optical structure may both be an imaging optics, or the first and second optical structure may both be a non-imaging optics. In such an embodiment, the shape and size of the first and second optical structure may be the same or different. Thus, 2024PF80107

[0047] 6 the shape and size of the first and second optical structure are unrelated to if the type of the first and second optical structure is the same or different.

[0048] In embodiments wherein the first and second optical structure are of the same type, the first and second optical structure may be configured to form a single optical structure which covers both the at least one N-LEDs and the plurality of M-LEDs. It is to be understood that the term “optical structure”, shall not be construed as limiting only to optical structure, meaning it does not exclude other formulations having the same meaning, such as e.g., projector lens, photonic structure, optical assembly and the like.

[0049] The plurality of M-LEDs in the lighting device may be arranged in an asymmetric pattern. The pattern of which the M-LEDs are arranged in may influence the second illumination pattern which in turn influences the main illumination pattern of the lighting device. Thus, arranging the M-LEDs in an asymmetric pattern may be advantageous when it is desired to obtain a specific asymmetric main illumination pattern.

[0050] The plurality of M-LEDs may further be arranged adjacent to the at least one N-LED. Because the M-LEDs and N-LED(s) are mounted on the same surface of the carrier this means that the M-LEDs are positioned alongside the at least one N-LED, preferably, on a single side of the N-LEDs. The main illumination pattern of the lightning device may thus be designed such that the at least one N-LED provides a first illumination pattern having a low resolution and being projected over a large area of the main illumination pattern. The plurality of M-LEDs may further provide a second illumination pattern, having a high resolution and being projected on a single side of the main illumination pattern. Such an embodiment is advantageous for example in a car headlight to provide illumination in a direction adjacent to the main direction of illumination.

[0051] Further, the plurality M-LEDs may be arranged around the at least one N- LED. It is to be understood that such an embodiment may be advantageous to provide a main illumination pattern having a bright and intense inner part and high resolution edges. The N- LEDs provide a first illumination pattern having a high intensity and brightness, while the M- LEDs may provide a second illumination pattern having a high resolution. Since the M-LEDs are arranged around the N-LEDs, the first and second illumination pattern may be superimposed thus forming the main illumination pattern.

[0052] Arranging the plurality of M-LEDs around the at least one N-LED enables many shapes of the main illumination pattern, e.g., a square shape or a triangular shape. In such an embodiment, the first and second optical structure are preferably of the same type, 2024PF80107

[0053] 7 meaning they are both either an imaging optics or they are both a non-imaging optics. Thus, they may be combined so as to form a single optical structure.

[0054] In particular, the plurality of M-LEDs may be arranged in a circular pattern around the at least one N-LEDs. In such an embodiment, the first and second optical structure are preferably of the same type, meaning they are both either an imaging optics or they are both a non-imaging optics. Since the first and second optical structure may be of the same type, they may even be combined so as to form a single optical structure. Such an embodiment is advantageous since it may provide a circular main illumination pattern having high brightness and sharp and well-defined edges.

[0055] The lighting device of the present invention may further comprise a third white LED light source arranged on the carrier and configured to provide a third white LED light.

[0056] The third white LED light source comprises a plurality of Z third light emitting diodes, I-LEDs. The I-LEDs are micrometer-sized LEDs and each of the I-LEDs comprises a die having a third surface area, SA3. SA3 has a largest spatial extent, SE3, that is less than or equal to 280 micrometers and more than or equal to 120 micrometers. It should be noted that the size above relates to the size of the LED chip.

[0057] Moreover, a ratio R2, defined by SA1 / SA3, is equal to or larger than 4. R1 defines that the size of the N-LED die and the size of the LLED die may not deviate such that R2 is less than 4. Further, a ratio R3, defined by SA3 / SA2, being equal to or larger than 4. R3 defines that the size of the M-LED die and the size of the LLED die may not deviate such that R3 is larger than 4.

[0058] The lighting device of the present invention may further comprise mini-LEDs. It is understood that the term “mini-LED” refers to a LED having a die with a size in the range of 100-200 micrometers. Incorporating mini-LEDs to the present invention may be advantageous because it enables even more shapes and sizes of the main illumination pattern. Further, mini-LEDs are, like N-LEDs, cheaper and easier to manufacture than M-LEDs, which makes it advantageous to incorporate mini-LEDs in some embodiments of the lighting device.

[0059] It shall also be noted that the terms “normal-sized LED”, “mini-LED” and “micro-LED” refers to LEDs having dies in different range of sizes. The terms used herein for specifying the size-ranges of LEDs shall not be restricted to the three mentioned. All terms for specifying size-ranges of LEDs contained in the art may be part of the present invention. 2024PF80107

[0060] 8

[0061] The number of M-LEDs in lighting device according to the present invention may be five times greater than the number of N-LEDs. The resolution of the main illumination pattern is mainly dependent on the resolution of the second illumination pattern provided by the second white LED light source. Thus, by increasing the number of M-LEDs in the plurality of M-LEDs, the resolution of the second illumination pattern may be improved. In other words, the higher the number of M-LEDs in the plurality of M-LEDs, the higher the resolution of the main illumination pattern. In an embodiment where the number of M-LEDs is five times greater than the number of N-LEDs, the resolution of the second illumination pattern is substantially high and may thus enable a sufficiently high resolution of the main illumination pattern.

[0062] The M-LEDs and / or the N-LEDs in the lighting device according to the present invention may be phosphor-converted LEDs. Phosphor-converted LEDs, pcLEDs, are LEDs which combine LED technology with phosphor materials. Phosphor material may open up a wide spectrum of colors by converting white LED light into a light having a specific color. Thus, it is possible to customize the color of white light emitted by the lighting device beyond what can be achieved by stand-alone LED technology.

[0063] In the lighting device of the present invention, the carrier may be a printed circuit board, PCB. The PCB carrier may in such an embodiment provide electrical means and mechanical connecting means to each LED comprised in the lightning device of the present invention.

[0064] In the present invention, the gap between the M-LEDs may be less than 0.5 times the gap between the N-LEDs. Since the resolution of the main illumination pattern is mainly dependent on the resolution of the second illumination pattern, it may be advantageous to design the second white LED light source such that the gap between the M- LEDs of the plurality of M-LEDs is less than 0.5 times the gap between the at least one N- LEDs of the first white LED light source. In such an embodiment, the resolution of the second illumination pattern is substantially high and may thus enable a sufficiently high resolution main illumination pattern.

[0065] The lighting device of the present invention may be a lamp or a luminaire.

[0066] It is noted that the invention relates to all possible combinations of features recited in the claims. Further objectives of, features of, and advantages with, the present invention will become apparent when studying the following detailed disclosure, the drawings and the appended claims. Those skilled in the art will realize that different features of the present invention can be combined to create embodiments other than those described in 2024PF80107

[0067] 9 the following. 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.

[0068] BRIEF DESCRIPTION OF THE DRAWINGS

[0069] Exemplifying embodiments will now be described in more detail, with reference to the following appended drawings:

[0070] As illustrated in the figures, the sizes of the elements and regions may be exaggerated for illustrative purposes and, thus, are provided to illustrate the general structures of the embodiments. Like reference numerals refer to like elements throughout.

[0071] Fig. 1 schematically shows a lighting device according to an exemplifying embodiment of the present invention;

[0072] Figs. 2a and b shows a top view of a lighting device according to two different exemplifying embodiments of the present invention;

[0073] Fig. 3 shows a top view of a lighting device according to an exemplifying embodiment of the present invention;

[0074] Fig. 4a illustrates a first white LED light source and the first optical structure;

[0075] Fig. 4b illustrates a second white LED light source and the second optical structure;

[0076] Figs. 5a and 6a depict a first illumination pattern provided by the first white LED light source and the first optical structure;

[0077] Figs. 5b and 6b depict a second illumination pattern provided by the second white LED light source and the second optical structure;

[0078] Figs. 5c and 6c depict a main illumination pattern provided by the lighting device according to the present invention;

[0079] Fig. 7 illustrates a top view and a side view of the lighting device according to the present invention;

[0080] Figs. 8a-8c show the first illumination pattern, the second illumination pattern and the main illumination pattern provided by the lighting device shown in Fig. 6;

[0081] Figs. 9a and 9b illustrate a side view of the first white LED light source and the second white LED light source according to the present invention;

[0082] Figs. lOa-lOc show the first illumination pattern, the second illumination pattern and the main illumination pattern provided by the lighting device shown in Fig. 8a-b; 2024PF80107

[0083] 10

[0084] DETAILED DESCRIPTION

[0085] Exemplifying embodiments will now be described more fully hereinafter with reference to the accompanying drawings in which currently preferred embodiments are shown. The 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.

[0086] Fig 1 shows a schematical embodiment of the lighting device 100 comprising a carrier 113, a first white LED light source 105, and a second white LED light source 106. The first white LED light source 105 and the second white LED light source 106 are arranged on the carrier 113. The first white LED light source 105 is configured to provide first white LED light and the second LED light source 106 is configured to provide second white LED light.

[0087] The first white LED light source 105 comprises one first light emitting diode, N-LED 101. The N-LED 101 is a normal-sized LED and comprises a die having a first surface area, SAL SAI has a largest spatial extent, SEI, that is greater than or equal to 300 micrometers.

[0088] The second white LED light source 106 comprises ten second light emitting diodes, M-LEDs 102. The M-LEDs 102 are micrometer-sized LEDs and each of the M-LEDs 102 comprises a die having a second surface area, SA2. SA2 has a largest spatial extent, SE2, that is less than or equal to 100 micrometers.

[0089] The plurality of M-LEDs 102 is arranged in a group of M-LEDs and confined within an area, A, 103, and the N-LED 101 are arranged outside the area A.

[0090] The N-LED 101 is covered by a first optical structure (not shown). The first optical structure is configured to collimate the first white LED light. The plurality of second light emitting diodes, MLEDs 102 is covered by a second optical structure (not shown). The second optical structure is configured to collimate the second white LED light.

[0091] The controller 104 is configured for individually controlling the first white LED light source 105 and second white LED light source 106.

[0092] Fig 2a and 2b each show a top view of examples of the lighting device 200. In Fig 2a, the first LED light source 205 comprises four N-LEDs 201 arranged adjacent each other in a square pattern. Moreover, the second LED light source 206 comprise eight M- LEDs 202 arranged in pairs adjacent to the first LED light source 205. Further, the third LED light source 214 comprises eight I-LEDs 215 arranged in pairs adjacent to the first LED light 2024PF80107

[0093] 11 source 205 and in between the pairs of M-LEDs 202 comprised in the second LED light source 206.

[0094] The number of M-LEDs 202 in the second white LED light source can be increased, as is shown in Fig. 2b. It is also shown that the size of the area A 103 is varied depending on the number of M-LEDs 202.

[0095] As illustrated, the number of M-LEDs 202 is greater in Fig. 2b compared to Fig. 2a. As described earlier, the N-LEDs 201 provide a first illumination pattern having a high intensity and brightness, whilst the plurality of M-LEDs 202 provides a second illumination pattern having a high resolution. Moreover, the I-LEDs 215 comprised in the third LED light source 214 provides a third illumination pattern (not shown).

[0096] Since the plurality of M-LEDs 202 and the plurality of I-LEDs are arranged around the N-LEDs 201, the first illumination pattern, the second illumination pattern and the third illumination pattern are superimposed and thus form a main illumination pattern. It should also be noted that by arranging the plurality of M-LEDs 202 and the plurality of I- LEDs around the N-LEDs 201, as in Fig. 2a, b, enables many shapes of the main illumination pattern, e.g., a square shape, rectangular shape or a triangular shape. Since the area A 103 comprises the plurality of M-LEDs 202, the size and shape of area A depends on the size and the shape of the M-LEDs 202 and the number of M-LEDs 202 comprised within the second while LED light source. Further, the I LEDs 215 and the N-LEDs 201 are arranged outside the area A and are independent of the properties of the plurality of M-LEDs 202. It should be noted that the M-LEDs in Fig. 2b are of different sizes.

[0097] Fig 3 illustrates a top view of a particular embodiment of the lighting device 300. In Fig 3, the first LED light source comprises one N-LED 301 arranged adjacent to the second LED light source. The second LED light source comprises seven M-LEDs 302. The plurality of M-LEDs 302 in the lighting device 300 is arranged in an asymmetric pattern. The pattern of which the M-LEDs are arranged in influences the second illumination pattern 511, which in turn influences the main illumination pattern 512 of the lighting device, shown in Fig 5b and c.

[0098] Fig 4a illustrates a schematical embodiment of the first white LED light source comprising one N-LED 401. As seen from the illustration, the N-LED 401, is covered by a first optical structure 407 which is a non-imaging optics. The first optical structure 407 is at least large enough to cover N-LED 401. The first optical structure 407 is configured to optimize the transfer of light from the first white LED light source 405 to the end-user, and thus form an intense and bright first illumination pattern 510 or 610 which can be seen in Fig. 2024PF80107

[0099] 12

[0100] 5a and Fig. 6a. However, the first illumination pattern 510, 610 emitted by the N-LED 401 of the first white LED light source 405 has a low resolution as can be seen in the outer edge of the first illumination pattern 510, 610 in Fig. 5a and Fig. 6a.

[0101] Fig. 4b illustrates a schematical example of the second white LED light source 406. The plurality of M-LEDs 402 shown in Fig. 4b, is covered by a second optical structure 408 which is an imaging optics. The second optical structure 408 is configured to collimate the second white LED light emitted by the second LED light source 406. The second optical structure 408 is at least as large as the area A, such that all of the M-LEDs 402 are covered by the second optical structure 408.

[0102] The second optical structure 408 is configured to provide a second illumination pattern 511, 611 shown in Fig 5b and Fig. 6b, respectively. The second illumination pattern 511, 611 has a high resolution which can be seen from the sharp edges Fig. 5b and Fig. 6b. As has been described earlier, the first white LED light source 405 provides a first illumination pattern 510, 610 and the second white LED light source 406 provides a second illumination pattern 511, 611 and depending on the desired effect, the shape and size of each illumination pattern may be varied by e.g., changing the number of N- LEDs 401 or changing the number of M-LEDs of the plurality of M-LEDs 402.

[0103] The first illumination pattern 510 and the second illumination pattern 511 shown in Fig. 5a and 5b, respectively, are superimposed and form a main illumination pattern 512 shown in Fig. 5c. As can be seen, the first illumination pattern 510 provides a high intensity and bright inner part to the main illumination pattern 512, whilst the second illumination pattern 511 has a high resolution which alleviates the low resolution of the first illumination pattern 510. Thus, the resulting main illumination pattern 512 have both an intense and bright inner part and a high resolution outer edge.

[0104] In analogy, the first illumination pattern 610, second illumination pattern 611 and main illumination pattern, 612 are further illustrated according to another embodiment of the present invention in Fig. 6a, b and c. In such an embodiment, the first white LED light source 405 and second white LED light source 406 are arranged in a rectangular shape such that both the first illumination pattern 610 and second illumination pattern 611, each has a rectangular shape, shown in Fig. 6a and b, respectively. Subsequently, Fig. 6c shows the main illumination pattern 612 which is formed by the superimposed first illumination pattern 610 and second illumination pattern 611.

[0105] A top view and a side-view of yet another embodiment of the present invention is illustrated in Fig 7. The N-LEDs 701 of the first white LED light source are 2024PF80107

[0106] 13 arranged in a square pattern. Furthermore, the plurality of M-LEDs 702 of different sizes is arranged in a substantially circular pattern around the N-LEDs 701. By arranging the N- LEDs 701 and the plurality of M-LEDs 702 in such a manner, it is possible to provide a first illumination pattern 810, shown in Fig. 8a, which has a shape of a plurality of squares, and a second illumination pattern 811, shown in Fig 8b, which has a substantially circular shape. This illumination pattern can be obtained by adjusting the controller such that both the MLEDs and the at least one N-LED are in the off-state in one of quadrants. Subsequently, the first illumination pattern 810 and the second illumination pattern 811 are superimposed and form a main illumination pattern 812 shown in Fig. 8c.

[0107] In the embodiment shown in Fig 7, the first optical structure is of the same type as the second optical structure, i.e., the first optical structure and second optical structure are both an imaging optics. Since the first and second optical structure are of the same type, the first and second optical structure is configured to form a single optical structure 708 which covers both the N-LEDs 701 and the plurality of M-LEDs 702.

[0108] Fig. 9a and b illustrates yet another embodiment of the present invention. The first optical structure 907 is a non-imaging optics and the second optical structure 908 is an imaging optics. As may be seen in Fig. 9b, the M-LEDs 902 are arranged in a matrix, wherein the area A 903 excludes the areas covered by the N-LED 901. The first illumination pattern 1010, the second illumination pattern 1011 and the main illumination pattern 1012 are shown in Fig. lOa-lOc .

[0109] Although the present invention has been described with reference to various embodiments, those skilled in the art will recognize that changes may be made without departing from the scope of the invention. It is intended that the detailed description be regarded as illustrative and that the appended claims including all the equivalents are intended to define the scope of the invention.

Claims

2024PF8010714CLAIMS:

1. A lighting device (100) configured to provide device light, the lighting device comprising: a carrier (113); a first white LED light source (105) arranged on a first major surface of the carrier (113) and configured to provide first white LED light; a second white LED light source (106) arranged on the first major surface of the carrier (113) and configured to provide second white LED light; wherein the first white LED light source (105) comprises at least one first light emitting diode, N-LED (101), the N-LED (101) comprising a die having a first surface area, SAI, wherein the SAI has a largest spatial extent, SEI, that is greater than or equal to 300 micrometers; wherein the second white LED light source (106) comprises a plurality of second light emitting diodes, M-LEDs (102), each of the M-LEDs (102) comprising a die having a second surface area, SA2, wherein the SA2 has a largest spatial extent, SE2, that is less than or equal to 100 micrometers; wherein a ratio, Rl, defined by SA1 / SA2, being equal to or larger than 10; wherein the plurality of M-LEDs (102) is arranged in a group of M-LEDs and confined within an area A, wherein the at least one N-LED (101) is arranged outside the area A, wherein the first white LED light has a first correlated color temperature, CCT1, in a range from 2000K to 6500K; and optionally having a color render index, CRI1, of at least 70; wherein the second white LED light has a second correlated color temperature, CCT2, in a range from 2000K to 6500K; and optionally having a color render index, CRI2, of at least 70; wherein in an operational mode of the lighting device the device light comprises the first LED light and the second LED light; wherein the at least one first light emitting diode, N-LED (101), is covered by a first optical structure (107) configured to collimate the first white LED light; and2024PF8010715 wherein the plurality of second light emitting diodes, M-LEDs (102), is covered by a second optical structure (108) and configured to collimate the second white LED light.

2. The lighting device (100) according to claim 1, wherein in an operational mode of the lighting device I CCT2-CCT1 I <300K.

3. The lighting device (100) according to claim 1 or 2, wherein the lighting device (100) further comprises a controller (104) configured to individually control the first white LED light provided by the first LED light source (105) and the second white LED light provided by second white LED light source (106).

4. The lighting device (100) according to any one of the preceding claims, wherein the M-LEDs (102) are arranged in an asymmetric pattern.

5. The lighting device (100) according to any one of the preceding claims, wherein the M-LEDs (102) are arranged adjacent to, and preferably on a single side of, the at least one N-LED (101).

6. The lighting device (100) according to any one of the preceding claims, wherein the first optical structure (107) has a shape and / or size being different from the shape and / or size of the second optical structure (108).

7. The lighting device (100) according to any one of the preceding clams, wherein the first optical structure (107) and the second optical structure (108) are selected from the optical structure types of a refractive optical element, a diffractive optical element and a reflective optical element, wherein the first optical structure (107) and the second optical structure (108) are of a different type.

8. The lighting device (100) according to any one of claims 1-5, wherein the first optical structure (107) and the second optical structure (108) are configured to form a single optical structure (708) covering both the at least one N-LED (701) and the plurality of M- LEDs (702).2024PF80107169. The lighting device (200) according to claim 8, wherein the M-LEDs (202) are arranged around the N-LEDs (201).

10. The lighting device (200) according to any one of the preceding claims, wherein the lighting device (200) further comprises a third white LED light source (214) arranged on the carrier (113) and configured to provide third white LED light; wherein the third white LED light source (214) comprises a plurality of Z third light emitting diodes, I-LEDs (215), each of the I-LEDs (215) comprising a die having a third surface area, SA3, wherein the SA3 has a largest spatial extent, SE3, that is less than or equal to 280 micrometers and more than or equal to 120 micrometers; wherein a ratio, R2, defined by SA1 / SA3, being equal to or larger than 4; and wherein a ratio, R3, defined by SA3 / SA2, being equal to or larger than 4.

11. The lighting device (200) according to any one of the preceding claims, wherein the number of the M-LEDs (202) is five times greater than the number of the N- LEDs (201).

12. The lighting device (100) according to any one of the preceding claims, wherein the M-LEDs (102) and N-LEDs (101) are phosphor-converted LEDs.

13. The lighting device (100) according to any one of the preceding claims, wherein the carrier (113) is a PCB.

14. The lighting device (200) according to any one of the preceding claims, wherein the gap between the M-LEDs (202) is less than 0.5 times the gaps between the N- LEDs (201).

15. The lighting device (100) according to any one of the preceding claims, wherein the lighting device is a lamp or a luminaire.

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