Light emitting diode device with support structure including patterned light modulation layer

Abstract

Light emitting devices, light emitting diode (LED) devices, and LED packages including solid state light emitting devices having support elements for improved near and far field emission are disclosed. The LED chips (12-1, 12-2) may be mounted to the support element (14) in a manner that directs light in a desired emission direction via the support element. The support element includes an optical structure that laterally diffuses and mixes light within the support element. The optical structures include various light modulation layers, such as light diffusing layers (40-1, 40-2) or light reflecting layers, arranged to effectively increase internal reflection for lateral diffusion of light. The patterned arrangement of the light modulation layer includes masking portions of direct emissions from the LED chip, thereby laterally redistributing the emissions to increase near-field and / or far-field uniformity over increased portions of the emission surface (14E). The described support elements may be well suited for low profile LED devices in which the device height is less than or equal to the device width.

Description

Technical Field

[0001] The present disclosure relates to a light-emitting device, a light-emitting diode, and a light-emitting diode package including a solid-state light-emitting device having a support element, the support element including one or more patterned light-modulating layers. Background Art

[0002] Solid-state lighting devices such as light-emitting diodes (LEDs) are increasingly being used in consumer and commercial applications. Advancements in LED technology have resulted in efficient and mechanically robust light sources with long service lives. As a result, modern LEDs have enabled a variety of new display applications (such as video screens) and are commonly used in general lighting applications, typically replacing incandescent and fluorescent light sources.

[0003] An LED is a solid-state device that converts electrical energy into light and typically includes one or more active layers (or active regions) of semiconductor material disposed between oppositely doped n-type and p-type layers. When a bias voltage is applied across the doped layers, holes and electrons are injected into the one or more active layers, where they recombine to produce emission, such as visible or ultraviolet emission. An LED chip typically includes an active region that can be made of, for example, silicon carbide, gallium nitride, gallium phosphide, aluminum nitride, gallium arsenide-based materials, and / or organic semiconductor materials. The photons generated by the active region are emitted in all directions.

[0004] LED packages have been developed that provide mechanical support, electrical connection, thermal management, encapsulation, and reflective surfaces for directing the light emission of an LED emitter in a desired direction. The light emission leaving the surface of the LED emitter can interact with various elements or surfaces of the corresponding LED package before escaping. As LED package structures continue to evolve for modern applications, there are still challenges in producing high-quality light with desired emission characteristics, especially as the overall LED package size continues to shrink.

[0005] The prior art continues to seek improved LEDs and solid-state lighting devices having desired lighting characteristics that can overcome the challenges associated with conventional lighting devices. Summary of the Invention

[0006] The present disclosure relates to light-emitting devices, light-emitting diode (LED) devices, and LED packages including solid-state light-emitting devices having support elements for improved near-field and far-field emission. The LED chip can be mounted to the support element in a manner that directs light in a desired emission direction via the support element. The support element includes an optical structure that laterally spreads and mixes light within the support element. The optical structure includes various light-modulating layers, such as light-diffusing layers or light-reflecting layers, which are arranged to effectively increase internal reflections for lateral spreading of light. The patterned arrangement of the light-modulating layers includes masking portions of the direct emission of the LED chip, thereby laterally redistributing the emission to increase near-field and / or far-field uniformity over an increased portion of the emission surface. The support elements described can be well-suited for low-profile LED devices in which the device height is less than or equal to the device width. Other patterned structures are also described that are not generally considered support elements but provide similar improvements in near-field and / or far-field emission.

[0007] In one aspect, an LED device includes: one or more LED chips; a light-transmissive layer located on the one or more LED chips; and a light-modulating layer patterned on the light-transmissive layer such that the light-transmissive layer is located between the light-modulating layer and the one or more LED chips. In certain embodiments, the light-modulating layer includes one or more of a light-diffusing layer, a light-scattering layer, and a light-reflecting layer. In certain embodiments, the light-modulating layer includes a light-diffusing layer, and wherein the light-diffusing layer includes a textured surface or light-diffusing particles dispersed within a light-transmissive material. In certain embodiments, the light-modulating layer includes a light-reflecting layer, and wherein the light-reflecting layer has a thickness less than or equal to 100 nanometers (nm). The LED package can further include a light-absorbing layer located on the light-modulating layer and on portions of the light-transmissive layer that are between portions of the light-modulating layer. In certain embodiments, the pattern includes discontinuous blocks of the light-modulating layer. In other embodiments, the pattern includes connected blocks of the light-modulating layer. The pattern can include blocks of the light-modulating layer that are aligned with the one or more LED chips.

[0008] In certain embodiments, the one or more LED chips include a first LED chip configured to provide a first peak wavelength in the range of 430 nanometers (nm) to 480 nm, a second LED chip configured to provide a second peak wavelength in the range of 500 nm to 570 nm, and a third LED chip configured to provide a third peak wavelength in the range of 600 nm to 750 nm.

[0009] The LED package may further include a substrate structure on which one or more LED chips are mounted, wherein the substrate structure includes an insulating submount or a lead frame structure having conductive traces. In a particular embodiment, the light modulating layer includes at least one anodized metal layer. The LED package may further include a current spreading layer located between the at least one anodized metal layer and the one or more LED chips. In a particular embodiment, the at least one anodized metal layer includes a light-absorbing colorant. In a particular embodiment, the at least one anodized metal layer includes local regions having different thicknesses from each other. In a particular embodiment, the pattern is a molded pattern or an embossed pattern. In a particular embodiment, the pattern includes individual features having dimensions in the range of 10 nm to 900 nm.

[0010] In another aspect, an LED device includes: one or more LED chips; a first light modulating layer located on the one or more LED chips; a second light modulating layer located on the first light modulating layer such that the first light modulating layer is closer to the one or more LED chips than the second light modulating layer; and a light transmissive layer located between the first light modulating layer and the second light modulating layer, and at least one of the first light modulating layer and the second light modulating layer is arranged in a pattern on the light transmissive layer. In a particular embodiment, each of the first light modulating layer and the second light modulating layer includes a light diffusing layer or a light reflecting layer.

[0011] In certain embodiments, the pattern includes one or more blocks of the second light modulating layer. The first light modulating layer may be arranged in an additional pattern that includes one or more blocks of the first light modulating layer. In certain embodiments, one or more blocks of the first light modulating layer are laterally spaced apart from one or more LED chips to form openings in the first light modulating layer that are aligned with the one or more LED chips. In certain embodiments, one or more blocks of the first light modulating layer are arranged between the one or more LED chips and the light transmissive layer such that the one or more blocks of the first light modulating layer are aligned with the one or more LED chips. In certain embodiments, one or more blocks of the first light modulating layer are arranged in a pattern complementary to the one or more blocks of the second light modulating layer. In certain embodiments, one or more blocks of the first light modulating layer are arranged in the same pattern as the one or more blocks of the second light modulating layer. In certain embodiments, one or more blocks of the second light modulating layer form a checkerboard pattern. In certain embodiments, one or more blocks of the second light modulating layer include alternating blocks that vary in surface area or shape. In certain embodiments, one or more blocks of the second light modulating layer include a first block disposed above the one or more LED chips and a plurality of second blocks disposed around the perimeter of the first block. In certain embodiments, one or more blocks of the second light modulating layer include a plurality of blocks with varying density across the LED device. In certain embodiments, at least one of the first light modulating layer and the second light modulating layer includes an anodized metal layer.

[0012] In another aspect, any of the foregoing aspects, alone or in combination, and / or the various individual aspects and features described herein can be combined for additional advantages. Unless stated to the contrary herein, any of the various features and elements disclosed herein can be combined with one or more other disclosed features and elements.

[0013] After reading the following detailed description of the preferred embodiments in connection with the accompanying drawings, those skilled in the art will understand the scope of the present disclosure and realize its additional aspects. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The drawings incorporated in and forming a part of this specification illustrate several aspects of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0015] Figure 1 is a cross-sectional view of a light emitting diode (LED) device including a plurality of LED chips mounted to a mounting surface of a support element.

[0016] Figure 2 is similar to the Figure 1 LED device, except that the support element further includes a diffusive material therein.

[0017] Figure 3 is similar to the LED device of Figure 1 and is a cross-sectional view of an LED device, with the difference that the support element includes a light-transmissive layer and a light-diffusing layer.

[0018] Figure 4 is an improved LED device relative to the LED device of Figure 3 and is a cross-sectional view of the LED device, wherein the support element includes a multi-layer structure that forms an internal mixing chamber for improving near-field and far-field emission while maintaining a low profile of the LED device.

[0019] Figure 5 is a cross-sectional view of an LED device similar to the LED device of Figure 4 for an embodiment in which the support element further includes a light-absorbing layer.

[0020] Figure 6 is similar to the LED device of Figure 4 and is a cross-sectional view of an LED device, with the difference that the support element includes a first light-reflecting layer and a second light-reflecting layer located on opposite sides of the light-transmissive layer.

[0021] Figure 7 is similar to the LED device of Figure 4 and is a cross-sectional view of an LED device, with the difference that the support element includes a light-transmissive layer located between a first light-modulating layer and a second light-modulating layer different from the first light-modulating layer.

[0022] Figure 8 is a cross-sectional view of an alternative configuration of the support element for an embodiment in which the first light-modulating layer and the second light-modulating layer are loaded with pores or bubbles to promote increased light scattering Figure 7 of

[0023] Figure 9 is a cross-sectional view of an alternative configuration of the support element for an embodiment in which the first light-modulating layer and the second light-modulating layer are loaded with oxide particles having a shape and / or particle size distribution or a medium having different refractive index values to promote increased light scattering Figure 7 of

[0024] Figure 10 is an exploded view of a general LED device similar to the LED device of Figure 4 and in which at least one light-modulating layer is patterned to adjust the emission pattern from the LED device.

[0025] Figure 11A is similar to the LED device of Figure 10 and is a cross-sectional view of an LED device including a first light-modulating layer and a second light-modulating layer on opposite sides of the light-transmissive layer.

[0026] Figure 11B is Figure 11A an exemplary top view of the LED device in

[0027] Figure 12 a cross-sectional view of an LED device similar to the LED devices of 11A and 11B, and wherein the first light modulation layer is also patterned.

[0028] Figure 13 is similar to the Figure 12 cross-sectional view of an LED device, and wherein the first light modulation layer is patterned with blocks aligned with the LED chip to block direct emission from the LED chip.

[0029] Figure 14 a cross-sectional view of an LED device similar to the Figure 12 LED device for an embodiment in which the pattern of the first light modulation layer is complementary to the pattern of the second light modulation layer.

[0030] Figure 15 a cross-sectional view of an LED device similar to the Figure 14 LED device for an embodiment in which the pattern of the first light modulation layer is the same as the pattern of the second light modulation layer.

[0031] Figure 16 shows a top view of an LED device for an embodiment in which the second light modulation layer is arranged in a checkerboard pattern on the LED device.

[0032] Figure 17 a top view of an LED device similar to the Figure 16 LED device for an embodiment in which the size of the blocks of the second light modulation layer varies along the LED device.

[0033] Figure 18 a top view of an LED device similar to the Figure 16 LED device for an embodiment in which the blocks of the second light modulation layer are formed discontinuously on the LED device.

[0034] Figure 19 a top view of an LED device similar to the Figure 16 LED device for an embodiment in which the shape and / or size of the blocks of the second light modulation layer varies on the LED device.

[0035] Figure 20 a top view of an LED device similar to the Figure 19 LED device for an embodiment in which the density of the blocks of the second light modulation layer varies on the LED device.

[0036] Figure 21is a top view of an LED device similar to that of Figure 16 for an embodiment where the pattern includes a single large block of a second light modulation layer, the single large block being aligned with the LED chip and covering a large portion of the top side of the LED device.

[0037] Figure 22 is a top view of an LED device similar to that of Figure 21 where a single block of the second light modulation layer is disposed in a band spanning between two opposite peripheral edges of the LED device.

[0038] Figure 23 is a top view of an LED device similar to that of Figure 22 where a single block of the second light modulation layer is provided with a surface area corresponding to the combined surface area or coverage area of the LED chip.

[0039] Figure 24 is a top view of an LED device similar to that of Figure 22 except that the second light modulation layer forms a pattern with individual blocks, each individual block being aligned or otherwise matched with the coverage area of a corresponding individual chip in the LED chip.

[0040] Figure 25A is an exploded cross-sectional view of a general LED device similar to that of Figure 10 for an embodiment where the substrate structure is a lead frame structure.

[0041] Figure 25B is Figure 25A an assembled cross-sectional view of the LED device of

[0042] Figure 26A is a partial exploded cross-sectional view of a general LED device similar to that of Figure 10 for an embodiment where the light modulation layer includes an anodized metal structure, and Figure 26A represents a manufacturing step before anodization.

[0043] Figure 26B is Figure 26A a partial exploded cross-sectional view of the LED device after anodization. DETAILED DESCRIPTION

[0044] The embodiments set forth below represent the necessary information that enables those skilled in the art to practice the embodiments and illustrate the best mode of practicing the embodiments. When reading the following description with reference to the drawings, those skilled in the art will understand the concepts of the present disclosure and will recognize applications of these concepts that are not specifically demonstrated herein. It should be understood that these concepts and applications fall within the scope of the present disclosure and the appended claims.

[0045] It will be understood that although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of the present disclosure, the first element may be referred to as the second element, and similarly, the second element may be referred to as the first element. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0046] It will be understood that when an element such as a layer, region, or substrate is referred to as "on another element" or "extending onto another element", the element can be directly on the other element or directly extend onto the other element, or there may also be intermediate elements. In contrast, when an element is referred to as "directly on another element" or "directly extending onto another element", there are no intermediate elements. Similarly, it will be understood that when an element such as a layer, region, or substrate is referred to as "above another element" or "extending above another element", the element can be directly above the other element or directly extend above the other element, or there may also be intermediate elements. In contrast, when an element is referred to as "directly above another element" or "directly extending above another element", there are no intermediate elements. It will also be understood that when an element is referred to as "connected" or "coupled" to another element, the element can be directly connected or coupled to the other element, or there may be intermediate elements. In contrast, when an element is referred to as "directly connected" or "directly coupled" to another element, there are no intermediate elements.

[0047] Relative terms such as "below" or "above" or "upper" or "lower" or "horizontal" or "vertical" may be used herein to describe the relationship of one element, layer, or region to another element, layer, or region as shown in the figures. It will be understood that these terms and those above are intended to encompass different orientations of the device in addition to the orientations depicted in the figures.

[0048] The terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the present disclosure. As used herein, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" are also intended to include the plural forms. It will be further understood that when used herein, the terms "comprises", "comprising", "includes", and / or "including" specify the presence of the described features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0049] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art. It will be further understood that terms used herein should be interpreted as having a meaning that is consistent with their meaning in the context of this specification and the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0050] Embodiments are described herein with reference to schematic illustrations of embodiments of the present disclosure. Accordingly, the actual dimensions of layers and elements may be different, and variations from the illustrated shapes are expected, for example, due to manufacturing techniques and / or tolerances. For example, regions illustrated or described as square or rectangular may have rounded or curved features, and regions shown as straight lines may have some irregularities. Thus, the regions shown in the figures are schematic, and their shapes are not intended to show the exact shape of regions of the device and are not intended to limit the scope of the present disclosure. Additionally, for illustrative purposes, the dimensions of a structure or region may be enlarged relative to other structures or regions, and thus, these dimensions or regions are provided to illustrate the general structure of the subject matter and may or may not be drawn to scale. Depending on the desired surface finish and manufacturing process details, the boundaries between individual adjacent layers may be sharp or gradual. Common elements between figures may be shown herein with common element numbers and may not be described subsequently.

[0051] The present disclosure relates to light-emitting devices, light-emitting diode (LED) devices, and LED packages including solid-state light-emitting devices having support elements for improved near-field and far-field emission. An LED chip may be mounted to a support element in a manner that directs light in a desired emission direction via the support element. The support element includes an optical structure that laterally diffuses and mixes light within the support element. The optical structure includes various light-modulating layers, such as light-diffusing layers or light-reflecting layers, which are arranged to effectively increase internal reflections for lateral diffusion of light. The patterned arrangement of the light-modulating layers includes portions that mask the direct emission of the LED chip, thereby laterally redistributing the emission to increase near-field and / or far-field uniformity over an increased portion of the emission surface. The support elements described herein may be well-suited for low-profile LED devices in which the device height is less than or equal to the device width. Other patterned structures are also described that are not generally considered support elements but provide similar improvements in near-field and / or far-field emission.

[0052] Before delving into the specific details of various aspects of the present disclosure, an overview of the various elements that may be included in an exemplary LED device of the present disclosure is provided for context. An LED chip generally includes an active LED structure or region that can have many different semiconductor layers arranged in various ways. The fabrication and operation of LEDs and their active structures are generally known in the art and are only briefly discussed herein. The layers of the active LED structure can be fabricated using known processes, where a suitable process is fabrication using metalorganic chemical vapor deposition. The layers of the active LED structure can include many different layers and typically include an active layer sandwiched between oppositely doped n-type and p-type epitaxial layers, all of which are continuously formed on a growth substrate. It should be understood that additional layers and elements can also be included in the active LED structure, including but not limited to buffer layers, nucleation layers, superlattice structures, undoped layers, cladding layers, contact layers, and current spreading and light extraction layers and elements. The active layer can include single quantum wells, multiple quantum wells, double heterostructures, or superlattice structures.

[0053] The active LED structure can be made from different material systems, where some material systems are III-nitride-based material systems. III-nitrides refer to those semiconductor compounds formed between nitrogen (N) and elements in Group III of the periodic table, typically aluminum (Al), gallium (Ga), and indium (In). Gallium nitride (GaN) is a commonly used binary compound. III-nitrides also refer to ternary and quaternary compounds such as aluminum gallium nitride (AlGaN), indium gallium nitride (InGaN), and aluminum indium gallium nitride (AlInGaN). For III-nitrides, silicon (Si) is a commonly used n-type dopant, and magnesium (Mg) is a commonly used p-type dopant. Thus, for III-nitride-based material systems, the active layer, n-type layer, and p-type layer can include one or more layers of GaN, AlGaN, InGaN, and AlInGaN that are undoped or doped with Si or Mg. Other material systems include silicon carbide (SiC), organic semiconductor materials, and other III-V systems such as gallium phosphide (GaP), gallium arsenide (GaAs), indium phosphide (InP), and related compounds.

[0054] An active LED structure can be grown on a growth substrate, which can include many materials such as sapphire, SiC, aluminum nitride (AlN), GaN, GaAs, glass, or silicon. SiC has certain advantages, such as a closer lattice match to group-III nitrides compared to other substrates, and produces high-quality group-III nitride films. SiC also has a very high thermal conductivity, such that the total output power of group-III nitride devices on SiC is not limited by the heat dissipation of the substrate. Sapphire is another common substrate for group-III nitrides and also has certain advantages, including low cost, established manufacturing processes, and good optical properties of light transmission.

[0055] Different embodiments of the active LED structure can emit light of different wavelengths depending on the composition of the active layer and the n-type and p-type layers. In a particular embodiment, the active LED structure emits blue light with a peak wavelength range of approximately 430 nanometers (nm) to 480 nm, or green light with a peak wavelength range of 500 nm to 570 nm, or red light with a peak wavelength range of 600 nm to 700 nm. In a particular embodiment, the active LED structure can be configured to emit light outside the visible spectrum, including one or more portions of the ultraviolet (UV) spectrum. The UV spectrum is generally divided into three wavelength range categories denoted by the letters A, B, and C. In this way, UV-A light is typically defined as having a peak wavelength range of 315 nm to 400 nm, UV-B is typically defined as having a peak wavelength range of 280 nm to 315 nm, and UV-C is typically defined as having a peak wavelength range of 100 nm to 280 nm. UV LEDs are particularly advantageous for use in applications related to the disinfection of microorganisms in air, water, and surfaces, etc. In other applications, the UV LED can also be provided with one or more lumiphoric materials to provide a polymeric emission with a wide spectrum and improved color quality for the LED package for visible light applications. In a particular aspect, a single LED package can include multiple LED chips, and one or more of the multiple LED chips can be configured to provide a different peak wavelength from the other LED chips.

[0056] The LED chip may also be covered with one or more luminescent materials (also referred to herein as emitters), such as phosphors, such that at least some of the light from the LED chip is absorbed by the one or more luminescent materials and is converted into one or more different wavelength spectra according to the properties of the one or more luminescent materials. In this regard, at least one luminescent material that receives at least a portion of the light generated by the LED light source may re-emit light having a peak wavelength different from that of the LED light source. The LED light source and one or more luminescent materials may be selected such that their combined output produces light having one or more desired properties (e.g., color, color point, intensity, spectral density, color rendering index, etc.). In a particular embodiment, the combined emission of the LED chips (optionally in combination with one or more luminescent materials) may be arranged to provide cool white, neutral white, or warm white light, such as in a color temperature range of 2500 Kelvin (K) to 10,000 K. In a particular embodiment, luminescent materials having cyan, green, amber, yellow, orange, and / or red peak wavelengths may be used. In some embodiments, the combined emission of the LED chip and one or more luminescent materials (e.g., phosphors) is an overall white combination. One or more phosphors may include phosphors that emit yellow (e.g., YAG:Ce), green (e.g., LuAg:Ce), and red (e.g., Ca i-x-y Sr x Eu y AlSiN3), and combinations thereof.

[0057] The luminescent materials described herein may be or include one or more of emitters, scintillators, luminescent inks, quantum dot materials, day glow tapes, etc. The luminescent materials may be provided by any suitable means, such as by direct coating on one or more surfaces of the LED, dispersion in a packaging material configured to cover one or more LEDs, embedding in an optical element or a support element, and / or coating on one or more optical elements or support elements (e.g., by powder coating, inkjet printing, etc.). In a particular embodiment, the luminescent materials may be down-converting or up-converting, and a combination of both down-converting materials and up-converting materials may be provided. In a particular embodiment, a plurality of different (e.g., different in composition) luminescent materials arranged to produce different peak wavelengths may be arranged to receive the emission from one or more LED chips.

[0058] As used herein, a layer or region of a light-emitting device may be considered "transparent" when at least 50% or at least 80% of the emitted radiation incident on the layer or region passes through the layer or region. Additionally, as used herein, a layer or region of an LED is considered "reflective" or acts as a "mirror" or "reflector" when more than 50% or at least 80% of the emitted radiation incident on the layer or region is reflected. In some embodiments, the emitted radiation includes visible light, such as blue and / or green LEDs with or without a luminescent material. In other embodiments, the emitted radiation may include invisible light. For example, in the context of GaN-based blue and / or green LEDs, silver (Ag) may be considered a reflective material (e.g., at least 80% reflective). In the case of UV LEDs, an appropriate material can be selected to provide a desired and in some embodiments high reflectivity and / or a desired and in some embodiments low absorption. In certain embodiments, a "light-transmissive" material may be configured to transmit at least 50% of the emitted radiation of a desired wavelength. In other embodiments, a "light-transmissive" material may be configured to have a lower value, such as transmitting at least 10% or at least 25% of the light of a desired wavelength while still being useful for a particular application and suppressing other wavelengths, such as ambient light and / or sunlight. In yet additional embodiments, the term "light-transmissive" may be used for applications where any useful light (such as the emission wavelength from an underlying LED) can pass through the material. The terms "transparent", "reflective", and "light-transmissive" may be defined with respect to a specific wavelength range, such as the wavelength range emitted by the LED chip and / or converted by any luminescent material. The specific values listed above are intended to describe the average value or property of an element or layer. It should be understood that variations in these properties can exist within or across such an element or layer.

[0059] As used herein, the term "opaque" refers to a material, surface, particle, etc. that is opaque or non-transmissive to light in at least a portion of the visible spectrum. In certain aspects, the term "opaque" may also apply to the entire visible spectrum. The term "non-transmissive to light" may be considered to transmit less than 20% or less than 10% of the received light or the received light of a particular wavelength. A material may be opaque further due to light absorption or light reflection. Some materials may be opaque at certain wavelengths and transparent at other wavelengths. As a non-limiting example, a red colorant can act as a color filter by absorbing light wavelengths below approximately 600 nm (where it is opaque) while transmitting light wavelengths above approximately 600 nm (where it is transparent). A layer may include a distribution of opaque material such that the layer remains light-transmissive.

[0060] The present disclosure can be used for LED chips having various geometries, such as a lateral geometry. An LED chip with a lateral geometry typically includes an anode electrical connection and a cathode electrical connection on the same side of the LED chip opposite to a substrate (such as a growth substrate). In a particular embodiment, an LED chip with a lateral geometry can be flip-chip mounted such that the anode connection and the cathode connection are on a face of the active LED structure opposite to the major emission surface of the LED chip. In this configuration, electrical traces or patterns can be provided on the mounting surface for providing electrical connections to the anode connection and the cathode connection of the LED chip. In a flip-chip configuration, the active LED structure is configured between the substrate of the LED chip and the mounting surface. Thus, light emitted from the active LED structure can pass through the substrate in a desired emission direction.

[0061] As described herein, the principles of the present disclosure can be applied to various embodiments having various LED chip sizes, including larger area chips as well as small LED chips and micro-LED chips. As used herein, a larger area LED chip can have a lateral dimension of up to about 2000 micrometers (μm), while a small LED chip can have a lateral dimension of about 100 μm, and a micro-LED chip can have a lateral dimension below 50 μm. In this way, depending on the application, the LED chips of the present disclosure can have a lateral dimension in the range of 20 μm to 2000 μm, or in the range of 20 μm to 1000 μm, or in the range of 20 μm to 100 μm, or in the range of 100 μm to 2000 μm.

[0062] According to aspects of the present disclosure, an LED package can include one or more elements, such as a light-emitting material, a encapsulant, a light modulating material, a lens, a superstrate or a support element, an adhesive element, and electrical contacts, etc., provided with one or more LED chips. A light modulating material can be arranged within the LED package to reflect or otherwise redirect light from the one or more LED chips in a desired emission direction or pattern. The term "superstrate" is used herein as a support element in an LED device, partly to avoid confusion with other conventional substrates or bases that can conventionally be part of an LED device, such as a growth or carrier substrate of an LED chip and / or a base of an LED package. The term "superstrate" is not intended to limit the orientation, position, and / or composition of the structure it describes, nor is it intended to limit the various optical, electrical, thermal, and mechanical properties beyond the description of the support element described herein. In a particular embodiment, the superstrate can be composed of a transparent material, a translucent material, or a light transmissive material for various wavelengths of light provided by the LED chip and / or the light-emitting material.

[0063] As used herein, the light modulating material can include many different materials, including light reflective materials that reflect or redirect light, light absorbing materials that absorb light, and materials that act as thixotropic agents. As used herein, the term "light reflection" refers to materials or particles that reflect, refract, scatter, or otherwise redirect light. For light reflective materials, the light modulating material can include at least one of fused silica, fumed silica, titanium dioxide (TiO2), zirconium dioxide (ZrO2), aluminum oxide (Al2O3), metal particles, glass fibers, and / or glass particles suspended in a binder (such as silicone or epoxy resin). In certain aspects, the particles can have a refractive index configured to refract light emission in a desired direction. In some aspects, the light reflective particles can also be referred to as light scattering particles. For light absorbing materials, the light modulating material can include at least one of carbon, silicon, metal, metal oxides (such as iron oxide, etc.), and organic particles suspended in a binder (such as silicone or epoxy resin). Exemplary organic particles can include various colorants, dyes, and / or absorption additives. The thixotropic material can include one or more of glass fillers and fumed silica. The light reflective materials and light absorbing materials can include nanoparticles. In certain embodiments, the light modulating material can include a generally white color to reflect and redirect light. In other embodiments, the light modulating material can include a generally opaque color, such as black or gray, for absorbing light and increasing contrast. In certain embodiments, the light modulating material includes both light reflective materials and light absorbing materials suspended in a binder. As used herein, a layer or coating of one or more light modulating materials can be referred to as a light modulating coating. In certain embodiments, the light modulating material or coating can be free of luminescent materials. The light modulating element can also refer to a modified surface that does not necessarily require the addition of particles, such as a texture for diffusing and / or scattering. In yet additional embodiments, the light modulating material can be provided in the form of a coating that is applied to the outer side or surface of a light emitting device to control light emission.

[0064] In certain applications, it is desirable to increase the manufacturing speed of LED devices. One way to increase the manufacturing speed is to assemble a number of components on a single support element (or a cover plate as described below), and then group them into an array of components. This can be particularly useful when producing an array of multi-color components for high-definition (HD) video displays. Multiple arrays can be produced as large sheets and then singulated into individual arrays, each of which includes a number of LED devices for each singulated portion. In this way, a single LED device can be filled with multiple LED chips having different emission colors (such as red, green, and blue, etc.) after singulation. In this regard, such LED devices can be well-suited for use as pixels within HD video displays and / or signage applications. In other embodiments, a larger array of LED chips can be formed together to provide an LED component, an LED patch, an LED screen, and / or an LED display.

[0065] In addition, elimination of various elements of conventional LED devices can streamline the manufacturing process, improve light quality, facilitate device miniaturization, and / or reduce costs. For example, an LED device can be assembled without using or having a conventional LED package base (e.g., a ceramic base with traces, a lead frame structure, a printed circuit board, etc.). This can be achieved by assembling the LED from the top side down such that the LED is assembled on a support element (such as a transparent cover plate or a light-transmissive layer), which will become the top-side outer surface in the finished product. Then, the components can be electrically connected via exposed electrical connection points on the opposite side of the LED. Thus, the device or apparatus can have no traditional base on the side of the LED opposite the light-transmissive side, e.g., the ceramic, metal, or other type of rigid material substrate to which the LED is typically attached. An LED device constructed from the top side down as described herein can be considered a complete LED device without such a rigid base. This does not mean that such LED devices cannot subsequently be assembled into larger (e.g., multi-component) devices that may include a traditional package base.

[0066] While such a single LED device with closely spaced LED chips of multiple colors may be well-suited for use as a pixel within an HD video display and / or a signage application, there are challenges in the near-field and / or far-field emission patterns from such a device. For example, when viewing a video display at various angles, the mismatched far-field emission patterns provided by different LED chips (e.g., red, blue, and green LED chips) within a single package may result in the appearance of color shifts. Emission variations may be caused by the different emission patterns of different color chips and their geometric arrangement within the LED package. In another example, near-field emission typically converges along the center of the LED device from the closely spaced LED chips, which results in a more pixelated appearance or a reduced fill factor within the video screen and display. In this regard, when multiple LED devices with a centrally-converging near-field emission pattern are assembled together, the so-called "screen door" effect is visible when darker lines are formed in the columns and rows along the boundaries of the LED devices within the display.

[0067] The support element according to the present disclosure provides an improved far-field emission pattern for increasing uniformity at wider viewing angles within the display and / or an improved near-field emission uniformity for increasing the fill factor within each LED device, thereby reducing the screen door effect in the display. The support element may include a laminated structure having a transparent cover plate and / or a light-transmissive layer, as well as any number of materials and optical structures that exhibit light-transmissive and / or light-scattering properties relative to the associated LED and / or light-emitting material. In a particular embodiment, the support element may include a laminated structure of individual layers or sub-layers that are configured to improve the near-field and / or far-field emission patterns, particularly for a light-emitting device having multiple chips that emit light at multiple peak wavelengths. The laminated film may generally be light-transmissive to light from the corresponding LED chips while also exhibiting one or more of the properties of light reflection, light refraction, light absorption, light scattering, and / or light diffusion. In a specific embodiment, an exemplary support element may include a light-transmissive layer sandwiched between two layers that have increased light-reflection, light-refraction, light-absorption, light-scattering, and / or light-diffusion properties relative to the light-transmissive layer. In this regard, the centrally-located light-transmissive layer may form a mixing chamber for light, which may propagate laterally along the support element and be internally reflected several times before finally escaping the LED device with improved emission uniformity. As used herein, the internal mixing chamber within the support element may also be referred to as an optical cavity.

[0068] Figure 1 is including a mounting surface 14 mounted to the support element 14 MCross-sectional view of the LED device 10 with multiple LED chips 12-1 to 12-2. For illustrative purposes, only two LED chips 12-1 to 12-2 are shown. However, according to the embodiment, the LED chips 12-1 to 12-2 may include any number of LED chips configured to emit light of the same or different wavelengths. For example, for a display application where the LED device 10 forms a display pixel, three LED chips configured to emit blue, green, and red light may be provided. Depending on the application, other color combinations may be provided, including white emission. Depending on the application, the LED chips 12-1 to 12-2 may include a variety of lateral dimensions, such as in the range of 20 μm to 2000 μm, or in the range of 20 μm to 1000 μm, or in the range of 20 μm to 100 μm, or in the range of 100 μm to 2000 μm. Small LED chips (e.g., approximately 100 μm to 300 μm + / - 50 μm) and micro LED chips (e.g., less than 100 μm) may be well-suited for pixels in an LED display.

[0069] The LED chips 12-1 to 12-2 may be mounted to the support element 14 through a chip mounting layer 16 that may be continuous or discontinuous on the mounting surface 14 of the support element 14. M The chip mounting layer 16 may be light-transmissive to the light wavelengths generated by the LED chips 12-1 to 12-2, where exemplary materials include silicone and / or epoxy resin. After the LED chips 12-1 to 12-2 are adhered to the support element 14 through the chip mounting layer 16, a encapsulant layer 18 may be applied around the outer edges of the LED chips 12-1 to 12-2 and optionally between the LED chips. The encapsulant layer 18 may be applied by one or more of dispensing, molding, stenciling, screen printing, spin coating, spraying, powder coating, or slot coating. The encapsulant layer 18 may include an electrically insulating material, such as one or more of epoxy resin, epoxy-polyester mixture, aliphatic urethane, triglycidyl isocyanurate (TGIC) polyester, non-TGIC polyester, silicone resin, silicone resin-modified polyester, silicone resin mixture, silicone resin-epoxy resin mixture, acrylic, polycarbonate, or any suitable combination thereof. In a particular embodiment, the encapsulant 18 may include a light modulating material for controlling the light output of the LED device 10. For example, the encapsulant 18 may include a light reflecting and / or light refracting material to redirect the light from the LED chips 12-1 to 12-2, or even a light absorbing material to provide increased contrast. Certain light reflecting and / or light refracting materials may exhibit a white appearance, while the light absorbing material may exhibit a dark or even black appearance. In a particular embodiment, the encapsulant layer 18 may contain a structure designed to increase its mechanical strength or other fillers designed to control the coefficient of thermal expansion (CTE).

[0070] The electrical connections for the LED chips 12-1 to 12-2 can be provided on the side of the LED chips 12-1 to 12-2 opposite to the support element 14. In other words, the LED chips 12-1 to 12-2 can be arranged between the support element 14 and the electrical connections for the LED chips 12-1 to 12-2. In this way, at least part of the light from the LED chips 12-1 to 12-2 can pass through the support element 14 without interacting with the electrical connections. The electrical connections can include device contact pads 20 that are electrically connected to one or more of the LED chips 12-1 to 12-2 via conductive paths 22, which can include but are not limited to conductive substrates including metals such as gold (Au) and / or copper (Cu), bump bonding, solder materials, wires, traces, and vias. Different conductive paths 22 can be coupled to corresponding chip contact pads 24. Depending on the arrangement and / or manufacturing sequence, the device contact pads 20 can include a single layer or multiple layers. Multiple conductive traces 26-1, 26-2 and insulating layers 28-1, 28-2 can also be employed to route the electrical connection between the device contact pads 20 and the chip contact pads 24. In a particular embodiment, the conductive traces 26-1, 26-2 can be embodied as patterned metal traces. For example, the conductive trace 26-1 can be patterned such that its sections are electrically coupled to one or more of the LED chips 12-1 to 12-2 and further extend over a portion of the encapsulant layer 18. In a particular embodiment, the conductive traces 26-1, 26-2, the insulating layers 28-1, 28-2 and the respective conductive paths 22 can form a fan-out circuit structure. In yet another embodiment, the conductive traces 26-1, 26-2, the insulating layers 28-1, 28-2, and the respective conductive paths 22 can be formed at the wafer level or panel level before the individual LED devices 10 are singulated.

[0071] An arrangement of the LED chips 12-1 to 12-2 relative to the support element 14 is provided such that light 30 escaping from the LED chips 12-1 to 12-2 of the LED device 10 can pass through the support element 14 and exit from the major emission surface 14 M opposite to the mounting surface 14 E . For illustrative purposes, the light 30 is shown as multiple arrows propagating in a direction away from the major emission surface 14 E . The arrows shown for the light 30 are not meant to be an exact representation of a particular light direction as in a ray trace diagram, but rather a conceptual representation of the intensity at the major emission surface 14 E . For an arrangement in which the support element 14 is substantially transparent to the light 30, the light 30 exiting the LED device 10 exits along the major emission surface 14 EThe central portion is more concentrated and is aligned with the LED chips 12-1 to 12-2. In this way, the LED device 10 can exhibit reduced color shift and uniformity of the far-field emission pattern and increased near-field bright spots, which reduce the fill factor in the LED display.

[0072] Figure 2 is a cross-sectional view of an LED device 32 similar to the LED device 10 of Figure 1 , except that the support element 14 further includes a diffusive material 34 therein. In this way, the support element 14 can diffuse and / or scatter the light 30 from the LED chips 12-1 to 12-2. However, for specific applications (such as LED display applications), the thickness of the support element 14 is typically thin, small, or reduced to maintain the overall low profile of the LED device 32. In this regard, the mere presence of the diffusive material 34 throughout the support element 14 may not be sufficient to substantially affect the near-field and far-field emission patterns of the light 30 leaving the LED device 32. Although the diffusive material 34 is typically added on the LED chips 12-1 to 12-2, as suggested by the lack of variation in the arrows of the light 30 between Figure 2 and Figure 1 , the desired effect on light uniformity may be minimal. Specifically, this effect is minimal when the thickness of the diffusive material 34 is thin.

[0073] Figure 3 is a cross-sectional view of an LED device 36 similar to the LED device 10 of Figure 1 , except that the support element 14 includes a light-transmissive layer 38 and a light-diffusing layer 40. In this way, the support element 14 of the LED device 36 incorporates Figure 1 the features of the LED device 10 of Figure 2 and the LED device 32 of

[0074] Figure 4 is relative to Figure 3Cross-sectional view of an improved LED device 42 of the LED device 36, wherein the support element 14 includes a multi-layer structure that forms an internal mixing chamber for improving near-field and far-field emission while also maintaining a low profile of the LED device 42. In a particular embodiment, the support element 14 may include a first light diffusing layer 40-1 and a second light diffusing layer 40-2 on opposite sides of the light transmissive layer 38. During operation, when the emissions from the LED chips 12-1 to 12-2 pass through the first light diffusing layer 40-1 and enter the light transmissive layer 38, they may be initially scattered. When interacting with the second light diffusing layer 40-2, the scattered emissions within the light transmissive layer 38 may be scattered a second time. Such a structure provides a scattering interface at the interfaces of the light diffusing layers 40-1, 40-2 with the opposite sides of the light transmissive layer 38, and the light transmissive layer 38 may form an internal mixing chamber defined by the scattering interfaces within the support element 14. In this way, the emissions within the light transmissive layer 38 may be scattered multiple times at the interfaces with the light diffusing layers 40-1, 40-2 before leaving the LED device 42, thereby laterally diffusing more emissions within the light transmissive layer 38. Consequently, the light 30 leaving the LED device 42 may exhibit improved near-field and far-field emission patterns.

[0075] In a particular embodiment, the light transmissive layer 38 may include glass, sapphire, epoxy resin, or other hard materials that are transmissive to the wavelengths of light generated by the LED chips 12-1 to 12-2. The light diffusing layers 40-1, 40-2 may include light diffusing particles dispersed within a light transmissive material, such as particles having a high refractive index or a refractive index different from that of the surrounding medium, or visible white colorants. As used herein, the light diffusing particles may include any of the light reflecting and / or light refracting particles described above with respect to the light modulating materials. The light diffusing layers 40-1, 40-2 may also include, for example, roughened and / or textured surfaces formed by etching. In a particular embodiment, the light transmissive layer 38 and the light diffusing layers 40-1, 40-2 may include the same material, such as glass, wherein the light diffusing layers 40-1, 40-2 further include light diffusing particles that are added to the material to form the light diffusing layers 40-1, 40-2. In other embodiments, the light diffusing layers 40-1, 40-2 may include other materials, such as sol-gel, spin-on glass, and / or sintered glass frit in which light diffusing particles are dispersed.

[0076] By forming an internal mixing chamber within the support element 14, improved emission can be achieved while also maintaining a low profile of the LED device 42. As used herein, low profile may refer to a relative dimension, wherein from the device contact pad 20 to the main emission surface 14 EThe height or thickness of the measured LED device 42 is less than or equal to the lateral width of the LED device 42 measured from the opposite peripheral edges of the support element 14. For example, the overall dimensions of the LED device 42 may include the above-mentioned height and width, which are less than or equal to 1000 micrometers (μm), or less than or equal to 500 μm, or in the range of 200 μm to 1000 μm, or in the range of 200 μm to 500 μm. To achieve such dimensions, the light diffusing layers 40-1, 40-2 and the light transmissive layer 38 may each have a thickness in the range of 50 μm to 200 μm, or in the range of 25 μm to 200 μm, or in the range of 20 μm to 200 μm. In yet another embodiment, the above-mentioned height and width may be in the range of 10 μm to 1000 μm, or in the range of 10 μm to 2000 μm.

[0077] Figure 5 is a cross-sectional view of an LED device 44 similar to the LED device 42 Figure 4 for an embodiment in which the support element 14 further includes a light absorbing layer 46. In a particular embodiment, the light absorbing layer 46 may be configured to be transmissive to most of the light 30 while also providing sufficient light absorbing properties for increasing contrast. For example, the light absorbing layer 46 may be configured to reduce the actual white appearance of the light diffusing layers 40-1, 40-2 at wide viewing angles. In a particular embodiment, the light absorbing layer 46 may include the same base material as the light diffusing layers 40-1, 40-2, which has light absorbing particles such as black particles instead of white particles. In yet another embodiment, the light absorbing particles may be dispersed in the light diffusing layer 40-2, and the separate light absorbing layer 46 may be omitted.

[0078] Figure 6 is a cross-sectional view of an LED device 48 similar to the Figure 4 LED device 42, except that the support element 14 includes first and second light reflecting layers 50-1, 50-2 located on opposite sides of the light transmissive layer 38. In this regard, the internal mixing chamber of the light transmissive layer 38 is defined by the reflective interfaces of the first and second light reflecting layers 50-1, 50-2. The first and second light reflecting layers 50-1, 50-2 may include thin layers or coatings of a reflective material that are generally light transmissive to the emissions from the LED chips 12-1 to 12-2. In this regard, some of the light may pass through the first and second light reflecting layers 50-1, 50-2 while other portions of the light may be reflected. Thus, the first and second light reflecting layers 50-1, 50-2 may provide the same as Figure 4The light diffusing layers 40-1 and 40-2 have similar functions. In a specific embodiment, the first and second light reflecting layers 50-1 and 50-2 can be embodied as metal layers, and the thickness of each metal layer is less than or equal to 50 nm or in the range of 2 nm to 50 nm. In other embodiments, the thickness can be greater than 50 nm or less than or equal to 100 nm. In a specific embodiment, the first and second light reflecting layers 50-1 and 50-2 include a thin layer of metal or a dielectric reflector, and the dielectric reflector includes a single dielectric layer or a stack of multiple dielectric layers.

[0079] Figure 7 is similar to Figure 4 FIG. is a cross-sectional view of an LED device 52 similar to the LED device 42, except that the support element 14 includes a light transmissive layer 38 located between a first light modulating layer 54-1 and a second light modulating layer 54-2 different from the first light modulating layer 54-1. For example, the second light modulating layer 54-2 can be configured to exhibit an increased light transmittance compared to the first light modulating layer 54-1. In this way, the light 30 propagating and / or scattering within the light transmissive layer 38 can preferentially pass through the second light modulating layer 54-2 and exit the LED device 52 in a desired emission direction. Thus, a reduced amount of the light 30 can pass through the first light modulating layer 54-1 and return towards the LED chips 12-1 and 12-2, where such emission can be susceptible to absorption. In other embodiments, the order can be reversed such that the first light modulating layer 54-1 is configured to exhibit an increased light transmittance compared to the second light modulating layer 54-2 to facilitate increased light diffusion and / or recycling within the light transmissive layer 38 before leaving the LED device 52.

[0080] In one embodiment for Figure 7 both the first light modulating layer 54-1 and the second light modulating layer 54-2 can include light reflecting layers 50-1 and 50-2 as described above for Figure 6 except that the first light modulating layer 54-1 can be configured to be more reflective of the peak wavelength of the light from the LED chips 12-1 to 12-2 than the second light modulating layer 54-2. For example, the first light modulating layer 54-1 can include a different reflective material from the second light modulating layer 54-2. In another example, the first and second light modulating layers 54-1 and 54-2 include the same material, and the second light modulating layer 54-2 can be formed with a reduced thickness compared to the first light modulating layer 54-1 to provide an increased light transmittance.

[0081] In one embodiment for Figure 7 both the first light modulating layer 54-1 and the second light modulating layer 54-2 can include light diffusing layers 40-1 and 40-2 as described above for Figure 4As described, the difference is that the first light modulation layer 54-1 can be configured to diffuse more light from the LED chips 12-1 to 12-2 than the second light modulation layer 54-2. For example, the first light modulation layer 54-1 can be loaded with a higher density of light diffusing particles than the second light modulation layer 54-2, and / or the second light modulation layer 54-2 can be formed to a reduced thickness compared to the first light modulation layer 54-1 to provide increased light transmittance.

[0082] exist Figure 7 In yet another embodiment of the present invention, the first light modulation layer 54-1 may include the Figure 6 The light reflecting layer 50-1 described above, and the second light modulation layer 54-2 may include the light reflecting layer 50-1 described above. Figure 4 In this manner, the first light modulation layer 54-1 can be embodied as a thin layer of reflective material that allows sufficient light to pass from the LED chips 12-1 to 12-2 to the light transmissive layer 38 while also limiting the amount of increased light within the light transmissive layer 38 to propagate back toward the LED chips 12-1 to 12-2. The second light modulation layer 54-2 can be used to diffuse light as light leaves the primary emitting surface 14 of the support element 14. E Further diffuse the light.

[0083] Figure 8 The first and second light modulating layers 54-1, 54-2 are loaded with air holes 56 or air pockets and / or bubbles to promote increased light scattering. Figure 7 54-1, 54-2 and the light transmissive layer 38 may include the same material, such as a ceramic material, glass, spin-on glass, or sintered glass. In other embodiments, one or more of the first and second light modulation layers 54-1, 54-2 and the light transmissive layer 38 may include materials that are different from each other. For example, the light transmissive layer 38 may include sapphire, and the first and second light modulation layers 54-1, 54-2 may include another ceramic, such as aluminum oxide having a certain porosity. For glass frit embodiments, the laminated structure of the first and second light modulation layers 54-1, 54-2 and the light transmissive layer 38 may be sintered together, and the size and / or density of the pores 56 may be controlled by selecting the particle size and / or the pressure of the laminated structure.

[0084] Figure 9 The first and second light modulation layers 54-1, 54-2 are loaded with oxide particles 58 having shapes and / or particle size distributions or media having different refractive index values ​​to promote increased light scattering.Figure 7 Cross-sectional view of an alternative configuration of the support element 14. In this regard, the bodies of the first and second light modulation layers 54-1, 54-2 may include a light-transmissive material, such as glass or ceramic material, and the oxide particles 58 may be dispersed therein to provide light diffusion characteristics. As with Figure 8 the configuration of, each of the first and second light modulation layers 54-1, 54-2 and the light-transmissive layer 38 may include the same material, such as ceramic material, glass, spin-on glass, or sintered glass frit. In other embodiments, one or more of the first and second light modulation layers 54-1, 54-2 and the light-transmissive layer 38 may include materials different from each other. For example, the light-transmissive layer 38 may include sapphire, and the first and second light modulation layers 54-1, 54-2 may include another ceramic, such as alumina having oxide particles 58. For the frit embodiments, the laminated structure of the first and second light modulation layers 54-1, 54-2 and the light-transmissive layer 38 may be sintered together. The size and / or density of the oxide particles 58 may be controlled by selecting the frit particle size or distribution and / or controlling the sintering time such that some of the glass may precipitate the oxide particles 58 within the first and second light modulation layers 54-1, 54-2. In another embodiment, the size and / or density of the oxide particles 58 may be controlled by adding an oxide precursor material loaded within the first and second light modulation layers 54-1, 54-2 before sintering. In yet another embodiment, the oxide particles 58 as Figure 9 shown may represent any medium that provides a refractive index value different from that of the light-transmissive layer 38 and the bodies of the first and second light modulation layers 54-1, 54-2.

[0085] In a particular embodiment, the support element 14 described above for any of Figures 4 to 9 may be formed of a laminated structure fired or sintered together. The laminated structure may include a light-transmissive material, such as ceramics (including alumina, sapphire), glass, spin-on glass, or sintered glass frit in the light-transmissive layer and / or light modulation layer described above. Light diffusion particles, air holes, oxide particles, and reflective layers may be employed as the light modulation layers to define the boundaries of an internal light mixing chamber that circulates light between these light modulation layers. Thus, the light within the mixing chamber may be laterally diffused before leaving, thereby providing improved near-field and far-field emission patterns. In a particular embodiment, such benefits may be achieved for a low-profile size where the overall device height is less than or equal to the overall device width. Any of the above-described support elements 14 and the associated LED devices may advantageously be formed at the wafer level before singulation of the individual devices. Further, when the LED device includes multiple LED chips of multiple colors, as described above for Figures 4 to 9Any of the described LED devices can be well suited to provide improved near-field and far-field emission. For example, a first LED chip can be configured to provide a first peak wavelength in the range of 430nm to 480nm, a second LED chip can be configured to provide a second peak wavelength in the range of 500nm to 570nm, and a third LED chip can be configured to provide a third peak wavelength in the range of 600nm to 700nm or in the range of 600nm to 750nm. Other embodiments can include one or more LED chips that provide a UV wavelength or wavelength range as described above.

[0086] In addition, the support element 14 is generally shown above as a three-layer structure; however, it should be recognized that the support element 14 may include any number of layers while falling within the scope of the present disclosure. For example, individual layers of the light diffusing layers 40-1, 40-2, the light reflecting layers 50-1, 50-2, and the light modulating layers 54-1, 54-2 may be embodied as a multi-layer structure. The principles disclosed herein relate to increasing the lateral diffusion of light by recycling light through the support element 14 with increased reflection and / or diffusion (e.g., specular reflection or diffuse reflection) from top and bottom regions or layers. These regions or layers can be anything from very thin (e.g., a metal reflector) to something thicker. As shown herein, these regions or layers can be uniform within themselves, have a gradient distribution characteristic, or be composed of multiple semi-uniform layers. In yet other embodiments, the above-described method for the support element 14 can be repeated. Figures 4 to 9 Individual layers of support elements 14 described in any one of the above to form multiple mixing chambers in a stacked manner within a single support element 14.

[0087] As described above, the LED devices of the present disclosure are well suited for use as pixels in LED display applications. In such applications, it is desirable to further improve the fill factor of light within each LED device to reduce the pixelated appearance within the display, especially when viewed at close range. In certain LED devices, the area of ​​the LED chip within the LED device is typically much smaller than the overall device footprint, thereby providing a higher intensity emission at the center of the LED device and sometimes resulting in a screen door effect when arranged as pixels in lines and columns within a display. According to additional embodiments of the present invention, additional configurations of optical structures including a light-transmitting layer and one or more patterned light modulation layers are disclosed, which further promote lateral diffusion of light within each LED device. One or more patterned light modulation layers may be provided to laterally redistribute higher intensity light within the LED device, thereby reducing or even masking the light output associated with bright spots that would otherwise exist directly above the LED chip.

[0088] Figure 10 is with Figure 4exploded view of a general LED device 60 similar to the LED device 42, and wherein at least one light modulation layer 54 is patterned to adjust the emission pattern from the LED device 60. As shown, the LED device 60 may include one or more of the LED chips 12-1 to 12-2. The light modulation layer 54 may be embodied as a patterned or segmented layer, which is similar to any one of the light diffusing layers 40-1, 40-2 described above for Figure 4 and / or any one of the light reflecting layers 50-1, 50-2 described above for Figure 6 . Similar to the previous embodiments, the LED device 60 may include any number of LED chips, including embodiments having red LED chips, blue LED chips, and green LED chips. In Figure 10 , the substrate structure 62 is generally shown below the LED chips 12-1 to 12-2. When present, the substrate structure 62 may provide primary support for the LED chips 12-1 to 12-2 and other components of the LED device 60. In this regard, the support element 14 may represent an additional layer formed on and / or supported by the substrate structure 62. The substrate structure 62 may include any one of the conductive traces 26-1, 26-2, insulating layers 28-1, 28-2, device contact pads 20, chip contact pads 24, and conductive paths 22 described and shown in Figures 1 to 7 . The substrate structure 62 may also be embodied as one of many known substrate structures in the art, such as a lead frame-based plastic leaded chip carrier (PLCC). In this case, assuming Figure 10 other components not shown, for example, a reflector along the side of the LED device 60 that redirects light to an area such as the light transmissive layer 38. In the case of a PLCC device, such a reflector typically constitutes the white plastic housing of the portion containing the leads.

[0089] As Figure 10As shown, the light modulation layer 54 is patterned such that it does not completely cover the light transmissive layer 38. The patterning can include a plurality of discontinuous blocks of the light modulation layer 54. Alternatively, the patterning can include continuous or connected blocks of the light modulation layer 54 having a distribution of various openings that break up the surface area of the light modulation layer 54. The patterning can be performed by a selective deposition or selective removal process. In other embodiments, the patterning can be provided by a molding or even an embossing process, where a shape is formed in a substrate material and the shape is filled with a light modulating material. The individual feature sizes of the light modulation layer 54 within the pattern can be on the nanoscale, such as in the range of 10 nm to 900 nm. The pattern of the light modulation layer 54 allows at least some of the light from the LED chips 12-1, 12-2 to be redirected by the light modulation layer 54 in specific regions. In other regions that do not include portions of the light modulation layer 54, the light can pass through more freely. In a particular embodiment, such patterning of the light modulation layer 54 can be arranged to avoid the appearance of a bright spot centered in the LED device 60, thereby increasing the fill factor of the light. For example, portions of the light modulation layer 54 can be vertically aligned with the LED chips 12-1 to 12-2 to reduce and / or redirect the light from the LED chips 12-1 to 12-2 away from the center of the LED device 60. As used herein, vertical alignment can be defined as an arrangement where a vertical line will intersect two elements. For example, a first vertical line passing through the LED chip 12-1 and a second vertical line passing through the LED chip 12-2 will both intersect portions of the light modulation layer 54. In a particular embodiment, other portions or blocks of the light modulation layer 54 can be arranged in other regions that are not directly above the LED chips 12-1 to 12-2 to further adjust the emission pattern. In a particular embodiment, a light absorption layer 46 can be provided on the light modulation layer 54 and / or the light transmissive layer 38.

[0090] Figure 11A is similar to Figure 10 LED device 60 and includes a cross-sectional view of an LED device 64 having first and second light modulation layers 54-1, 54-2 on opposite sides of the light transmissive layer 38. In Figure 11A this case, the second light modulation layer 54-2 located above the light transmissive layer 38 relative to the LED chips 12-1, 12-2 is patterned, while the first light modulation layer 54-1 continuously covers the light transmissive layer 38. In this way, once the light 30 propagates within the light transmissive layer 38, such light 30 can more easily pass through the patterned second light modulation layer 54-2 with a desired emission distribution. However, it should be understood that the order can be reversed such that the first light modulation layer 54-1 is patterned to provide a different light emission pattern. By means of the patterning, local mixing chambers that promote local light recycling are formed on portions of the support element 14 that are defined by the first and second light modulation layers 54-1, 54-2.

[0091] As shown in 11A, the central block of the second light modulation layer 54-2 is vertically aligned over the LED chips 12-1, 12-2. In a particular embodiment, the block of the second light modulation layer 54-2 includes an area large enough to extend laterally beyond the peripheral edges of the LED chips 12-1, 12-2. The second light modulation layer 54-2 may also include blocks disposed closer to the outer edge portion of the LED device 64 to further adjust the emission pattern. The light absorption layer 46, when present, may be disposed over the blocks of the second light modulation layer 54-2 and optionally over portions of the light transmissive layer 38 that are located between the blocks or portions of the second light modulation layer 54-2. In a particular embodiment, the pattern of the light absorption layer 46 may be the same as that of the second light modulation layer 54-2, while in other embodiments, the light absorption layer 46 may have a pattern complementary to that of the second light modulation layer 54-2.

[0092] Figure 11B Is Figure 11A An exemplary top view of the LED device 64. As shown, the central block of the second light modulation layer 54-2 is located at the center, while a plurality of smaller blocks of the second light modulation layer 54-2 are radially disposed from the peripheral edge of the LED device 64 in an inlaid manner. In this regard, a portion of the light from the Figure 11A LED chips 12-1, 12-2 can be redirected laterally towards the peripheral edge away from the center of the LED device 64, and this light can be further redirected laterally at various local positions near the peripheral edge. In the context of the LED device 64 forming a pixel in an LED display, the arrangement of the second light modulation layer 54-2 can reduce and / or prevent direct viewing of the Figure 11A underlying LED chips 12-1 to 12-2.

[0093] Figure 12 Is similar to Figure 11A And Figure 11B A cross-sectional view of the LED device 66 similar to the LED device 64, and wherein the first light modulation layer 54-1 is also patterned. Thus, both the first and second light modulation layers 54-1, 54-2 can be patterned on opposite sides of the light transmissive layer 38. In a particular embodiment, the pattern of the second light modulation layer 54-2 is the same as that of the Figure 11ASimilarly, additional patterns of the first light modulation layer 54-1 are provided. For example, the first light modulation layer 54-1 may be formed in a block that is laterally spaced apart from the LED chips 12-1, 12-2, thereby forming an opening in the first light modulation layer 54-1 that is vertically aligned with the LED chips 12-1, 12-2 to allow an increased amount of light to enter the light-transmissive layer 38. Such an arrangement may be particularly suitable for embodiments in which the first light modulation layer 54-1 includes a layer having an increased reflectivity compared to the second light modulation layer 54-2. In this way, light can freely pass from the LED chips 12-1, 12-2 into the light-transmissive layer 38, while the light propagating laterally within the light-transmissive layer 38 can be reflected in a desired emission direction. As described above, the pattern of the light absorption layer 46 may be the same as or complementary to the second light modulation layer 54-2.

[0094] Figure 13 is similar to Figure 12 FIG. 10 is a cross-sectional view of an LED device 68 that is similar to the LED device 66 of FIG. 9, and in which the first light modulation layer 54-1 is patterned with blocks aligned with the LED chips 12-1, 12-2 to block direct emission from the LED chips 12-1, 12-2. As shown, the blocks of the first light modulation layer 54-1 may be disposed between the top surfaces of the LED chips 12-1, 12-2 and the light-transmissive layer 38, thereby laterally redirecting the emission from the LED chips 12-1, 12-2 before it enters the light-transmissive layer 38. In this way, the bright spots associated with the positions of the LED chips 12-1, 12-2 in the light 30 exiting the LED device 68 can be reduced. As Figure 13 further shown in FIG. 11, the blocks of the second light modulation layer 54-2 may be distributed over the light-transmissive layer 38 without completely covering the LED chips 12-1, 12-2. For such an arrangement, one or more of the chip attachment layer 16 and the encapsulant 18 may serve as a lateral diffusion layer that is at least partially light-transmissive and propagates away from the LED chips 12-1 to 12-2 before the light is transmitted into the light-transmissive layer 38. If the chip attachment layer 16 covers a sufficient surface area of the light-transmissive layer 38 adjacent to the LED chips 12-1 to 12-2, the encapsulant 18 may be configured to have an increased reflectivity, such as including white reflective particles. As described above, the pattern of the light absorption layer 46 may be the same as or complementary to the second light modulation layer 54-2.

[0095] Figure 14 FIG. 12 is similar to Figure 12Cross-sectional views of LED device 66 similar to LED device 70. As shown, complementary patterns provide an arrangement in which the blocks of the first light modulation layer 54-1 are vertically aligned with the openings of the second light modulation layer 54-2. In this way, variations in the amount of light passing through each of the first and second light modulation layers 54-1, 54-2 can be cancelled out to improve overall emission uniformity. As described above, the pattern of the light absorption layer 46 can be the same as or complementary to the second light modulation layer 54-2.

[0096] Figure 15 is a cross-sectional view of LED device 72 similar to Figure 14 LED device 70 for an embodiment in which the pattern of the first light modulation layer 54-1 is the same as the pattern of the second light modulation layer 54-2. As shown, the same patterns provide an arrangement in which the blocks of the first light modulation layer 54-1 are vertically aligned with the blocks of the second light modulation layer 54-2. In this way, the openings in the first and second light modulation layers 54-1, 54-2 can be aligned to adjust the increasing light emission along the LED device 72. As described above, the pattern of the light absorption layer 46 can be the same as or complementary to the second light modulation layer 54-2.

[0097] Figures 16 to 24 Shows various patterns of the second light modulation layer 54-2 relative to the LED chips 12-1 to 12-3 according to aspects of the present invention that can provide improved near-field and far-field emission uniformity. The first light modulation layer 54-1 can be omitted or arranged in any of the arrangements shown in Figure 11A , Figure 12 and Figure 13 In additional embodiments, the first light modulation layer 54-1 can be arranged in a pattern complementary to the second light modulation layer 54-2 of Figures 18 to 24 in a manner similar to that described above for Figure 14 In other embodiments, the first light modulation layer 54-1 can be arranged in a pattern the same as the second light modulation layer 54-2 of Figures 18 to 24 in a manner similar to that described above for Figure 15 The different patterns of the second light modulation layer 54-2 can include blocks having different shapes, including squares, rectangles, triangles, circles, ellipses, and other shapes, as well as combinations thereof. The different patterns can also be arranged as more randomized or noisy patterns, such as a Gaussian noise distribution, especially for smaller structural dimensions, to reduce light interference effects. The illustrations are conceptual and are not intended to indicate the relative sizes between the various patterns, the LED chips 12-1 to 12-3, and the overall LED device. The size of the patterns can be anywhere from sub-microns to the size of the corresponding LED device, while the LED chips 12-1 to 12-3 are typically many microns, for example more than 100 μm. In Figures 16 to 24In each of them, the coverage areas of the LED chips 12-1 to 12-3 are indicated by overlapping dashed boxes.

[0098] Figure 16 A top view of the LED device 74 showing an embodiment in which the second light modulation layer 54-2 is arranged in a checkerboard pattern on the LED device 74. Thus, for improved uniformity, the openings of the second light modulation layer 54-2 are evenly distributed on the LED device 74. In a particular embodiment, the checkerboard nature of the pattern can provide connected corners of the blocks of the second light modulation layer 54-2.

[0099] Figure 17 is a top view of an LED device 76 similar to the Figure 16 LED device 74 for an embodiment in which the size of the blocks of the second light modulation layer 54-2 varies along the LED device 76. For example, the pattern of the blocks of the second light modulation layer 54-2 can alternate between smaller surface area blocks and larger surface area blocks on the LED device 76. It should be noted that only the smaller surface area blocks can be arranged closest to the outer edge of the LED device 76, where light emission can be reduced in a conventional device.

[0100] Figure 18 is a top view of an LED device 78 similar to the Figure 16 LED device 74 for an embodiment in which the blocks of the second light modulation layer 54-2 are formed discontinuously on the LED device 78. In this way, Figure 16 an increased surface area without the second light modulation layer 54-2 is provided for the LED device 78. Depending on the brightness levels of the LED chips 12-1 to 12-3, this arrangement can be beneficial in reducing any appearance of the pattern of the second light modulation layer 54-2. In other embodiments, the pattern of the second light modulation layer 54-2 shown can be complementary, such that the shaded squares represent the holes or openings of the second light modulation layer 54-2.

[0101] Figure 19 is a top view of an LED device 80 similar to the Figure 16Top views of LED device 80 similar to LED device 74. For example, the larger rectangular block of the second light modulation layer 54-2 can be arranged to cover the areas of LED chips 12-1 to 12-3, thereby masking their appearance and reducing the higher direct emission intensity at the center of LED device 80. Additionally, other blocks of the second light modulation layer 54-2 are arranged around the periphery of the larger rectangular block. Such additional blocks can be arranged to have a circular or other rounded shape, which reduces the sharp corners of the second light modulation layer 54-2 for improved emission uniformity. In other embodiments, the circular pattern of the second light modulation layer 54-2 shown can be complementary, such that the shaded circles represent holes or openings in the second light modulation layer 54-2. In yet additional embodiments, many other patterns of the second light modulation layer 54-2 for similar purposes are envisioned. For example, the central rectangle of the second light modulation layer 54-2 aligned with LED chips 12-1 to 12-3 can be replaced with a checkerboard pattern such that portions of the checkerboard pattern have small openings passing through the checkerboard pattern.

[0102] Figure 20 is a top view of LED device 82 similar to Figure 19 LED device 80 for an embodiment where the density of the blocks of the second light modulation layer 54-2 varies over LED device 82. For example, higher density blocks of the second light modulation layer 54-2 can be provided in the regions corresponding to LED chips 12-1 to 12-3, thereby at least partially masking their appearance and reducing the higher emission intensity at the center of LED device 82. In other embodiments, the circular pattern of the second light modulation layer 54-2 shown can be complementary, such that the shaded circles represent holes or openings in the second light modulation layer 54-2.

[0103] Figure 21 is a top view of LED device 84 similar to Figure 16 LED device 74 for an embodiment where the pattern includes a single block of the second light modulation layer 54-2 aligned with LED chips 12-1 to 12-3. As shown, the block of the second light modulation layer 54-2 can cover a larger portion of LED device 84, which is centered and generally associated with the bright emission spot in a conventional device. In this regard, the second light modulation layer 54-2 can allow for reduced central emission while laterally redirecting other emissions to escape near the peripheral edges of LED device 84.

[0104] Figure 22 is similar to Figure 21FIG. 8 is a top view of an LED device 84 similar to an LED device 86, wherein a single section of the second light modulation layer 54-2 is disposed in a band spanning between two opposing peripheral edges of the LED device 84. In certain embodiments, a single section of the second light modulation layer 54-2 may span completely between the two opposing peripheral edges.

[0105] Figure 23 is with Figure 22 86, wherein a single block of the second light modulation layer 54-2 is provided with a surface area corresponding to the combined surface area or footprint of the LED chips 12-1 to 12-3. In this regard, the second light modulation layer 54-2 can mask the appearance of the LED chips 12-1 to 12-3 and / or reduce the emission intensity at the central portion of the LED device 88 without occupying a large area of ​​the LED device 88.

[0106] Figure 24 is with Figure 22 LED device 88 is similar to a top view of LED device 90 , except that second light modulating layer 54 - 2 is formed into a pattern having individual blocks, each of which is aligned with or otherwise matches the footprint of a corresponding individual chip in LED chips 12 - 1 to 12 - 3 . Figure 23 This arrangement can mask the appearance of the LED chips 12 - 1 to 12 - 3 and / or reduce the emission intensity at the central portion of the LED device 90 without occupying a large area of ​​the LED device 90 .

[0107] It should be understood that the above-described pattern of the second light modulating layer 54-2 can be at or near 0% transmission, effectively blocking and redirecting all incident light, or have any intermediate % transmission, wherein a certain amount of light is redirected and other portions of the light are allowed to pass through. In addition, the border or pattern edge of the second light modulating layer 54-2 can gradually change from one transmission amount or hue to another, thereby having a so-called "soft" edge.

[0108] As mentioned above, for Figures 10 to 24 The substrate structure 62 of any of the previously described embodiments may be embodied in various structures, such as an insulating base with conductive traces or a lead frame structure including a PLCC LED package. Figure 25A This is for an embodiment in which the base structure 62 is a lead frame structure. Figure 10Exploded cross-sectional view of a general LED device 92 similar to the LED device 60. In this regard, the substrate structure 62 includes a lead frame 94 and a corresponding housing 96. The lead frame 94 provides electrical connection to the LED chips 12-1 to 12-2, and in some cases, the LED chips 12-1 to 12-2 are mounted on a portion of the lead frame 94 and wire bonded to another portion of the lead frame 94. For illustrative purposes, wire bonding is generally shown in Figure 25A as a curve connecting the LED chips 12-1 to 12-2 to a portion of the lead frame 94. It should be understood that other arrangements of wire bonding can also be implemented. In other arrangements, one or more of the LED chips 12-1 to 12-2 can be flip-chip mounted to the lead frame 94 without wire bonding. The housing 96 can include a recess having sidewalls, and the LED chips 12-1 to 12-2 reside in the recess. In a particular embodiment, the sidewalls of the housing 96 can be chamfered. The light modulation layer 38 can be shaped to fit within the recess of the housing 96, or the light modulation layer 38 can be formed within the recess to conform to the shape of the recess. The light modulation layer 54 and the optional light absorption layer 46 can be provided as described above. One or more portions of one or more of the light modulation layer 54 and the light absorption layer 46 can generally conform to the shape of the light modulation layer 38, which can be flat, convex, concave, or lens-shaped. Figure 25B is Figure 25A an assembled cross-sectional view of the LED package 92.

[0109] In a particular aspect, the light modulation layer of the present disclosure can be embodied as an anodized metal layer, such as anodized aluminum. Anodization is an electrochemical process for forming a metal oxide layer at the surface of a metal. In the case of aluminum, anodization forms an aluminum oxide layer or film at the surface of the bulk aluminum. In a particular aspect, the aluminum oxide layer of anodized aluminum can be formed with a porous structure. When the anodized aluminum is thin enough, the porous structure can allow light to pass through. Other portions of the porous structure can be filled with a colorant and then sealed to provide other optical properties for the LED device. For example, as described above, a black colorant or tint can be provided in a particular area to provide local light absorption characteristics.

[0110] Figure 26A and Figure 26B is a partially exploded cross-sectional view of a general LED device 98 similar to the Figure 10 LED device 60 for an embodiment in which the light modulation layer 54 includes an anodized metal structure (such as anodized aluminum). Figure 26A represents the light modulation layer 54 before it is anodized, while Figure 26BRepresents the light modulation layer 54 after anodization. The LED device 98 may include the LED chips 12-1 to 12-2, the light-transmitting layer 38, and the substrate structure 62, as described above. The light modulation layer 54 may include a patterned metal layer 100 arranged in a manner similar to any pattern of the light modulation layer 54 shown in the previous embodiments. As Figure 26B shown, the top portion of the patterned metal layer 100 may form a metal oxide 100' after anodization. In addition, the sidewall surfaces of the patterned metal layer 100 may have an anodized surface. As shown in the figure, the patterned metal layer, which is an anodized metal layer, may be formed with local regions having different thicknesses from each other. In a particular embodiment, the metal oxide 100' may be dyed with a light-absorbing colorant or color (such as a black colorant) to provide different emission adjustment characteristics, such as a top matte finish for improving contrast. The bottom portion of the patterned metal layer 100 has an unoxidized metal portion and can thus provide increased light reflectivity for light passing through the light-transmitting layer 38.

[0111] As Figure 26A shown, the light modulation layer 54 may further include a plurality of optional layers that assist the anodization process. For example, an additional metal layer 102 and / or a current diffusion layer 104 may be formed between the patterned metal layer 100 and the light-transmitting layer 38 to provide current flow to respective regions as required by the anodization process. The current diffusion layer 104 may be conductive and at least partially light-transmissive to light from the LED chips 12-1 to 12-2. As Figure 26B shown, the additional metal layer 102 may also be anodized to form a metal oxide 102' during the anodization process. When thin enough, the porosity of the metal oxide 102' may provide a light path for light to travel between the patterned metal layers 100. In a particular embodiment, both the patterned metal layer 100 and the additional metal layer 102 include aluminum. The current diffusion layer 104 may include indium tin oxide or the like, which can promote the complete anodization of the additional metal layer 102 by maintaining conductivity. In this way, the metal oxide 102' of the additional metal layer 102 may be formed with increased porosity such that the metal oxide 102' is light-transmissive or even transparent.

[0112] In other embodiments, the additional metal layer 102 and / or the current spreading layer 104 may be omitted. In such an embodiment, the patterned metal layer 100 with the metal oxide 100' may be formed by blanket metal deposition (such as evaporation or sputtering), followed by anodization, and then the anodized structure may be further patterned. In either case, with or without the additional metal layer 102 and / or the current spreading layer 104, the thickness of the anodization process and / or the patterned metal layer 100 may be adjusted to adjust the optical properties of the light modulation layer 54.

[0113] Although Figure 26A and 26B provided in the case where the light modulation layer 54 is disposed on a side of the light transmissive layer 38 farther from the LED chips 12-1 to 12-2, it is contemplated that the anodized metal layer may also be disposed on a side of the light transmissive layer 38 closest to the LED chips 12-1 to 12-2. For example, one or more of the light modulation layers 54-1, 54-2 as Figure 12 shown may be embodied as an anodized metal layer.

[0114] It is contemplated that any one of the foregoing aspects and / or the individual aspects and features described herein may be combined to obtain additional advantages. Unless stated to the contrary herein, any one of the various embodiments disclosed herein may be combined with one or more other disclosed embodiments.

[0115] Those skilled in the art will recognize improvements and modifications to the preferred embodiments of the present disclosure. All such improvements and modifications are considered to be within the scope of the concepts disclosed herein and the subsequent claims.

Claims

1. An LED device, comprising: One or more LED chips; And A support element, on which the one or more LED chips are mounted, wherein the support element is configured to be light-transmissive for the wavelength of light generated by the one or more LED chips, and the support element includes an internal mixing chamber that laterally diffuses light within the support element.

2. The LED device according to claim 1, wherein, The internal mixing chamber is formed by a light-transmissive layer located between a first light-diffusing layer and a second light-diffusing layer.

3. The LED device according to claim 2, wherein, At least one of the first light-diffusing layer and the second light-diffusing layer includes a multi-layer structure.

4. The LED device according to claim 2, wherein, The light-transmissive layer includes glass, and the first light-diffusing layer and the second light-diffusing layer include glass having light-diffusing particles.

5. The LED device according to claim 4, wherein, The light-diffusing particles include particles having a refractive index different from that of the glass.

6. The LED device according to claim 2, wherein, The light-transmissive layer, the first light-diffusing layer, and the second light-diffusing layer each have a thickness in the range of 20 micrometers (μm) to 200 μm.

7. The LED device according to claim 2, wherein, The support element further includes a light-absorbing layer located on the second light-diffusing layer.

8. The LED device according to claim 8, wherein, The light-absorbing layer includes light-diffusing particles dispersed in a light-transmissive material.

9. The LED device according to claim 1, wherein, The one or more LED chips are mounted to a mounting surface of the support element, and an opposite surface of the support element forms a main emission surface of the LED device.

10. The LED device according to claim 9, further comprising contact pads located on a side of the one or more LED chips opposite to the support element, wherein, The height of the LED device measured from the contact pad to the main emission surface is less than or equal to the width of the support element measured between opposite peripheral edges of the support element.

11. The LED device according to claim 10, wherein, The height and the width are in the range of 200 micrometers (μm) to 1000 μm.

12. The LED device according to claim 1, wherein, The internal mixing chamber is formed by a light-transmissive layer located between a first light-reflecting layer and a second light-reflecting layer.

13. The LED device according to claim 12, wherein, The first light-reflecting layer and the second light-reflecting layer each have a thickness less than or equal to 0.05 micrometers (μm).

14. The LED device according to claim 1, wherein, The one or more LED chips include a first LED chip, a second LED chip, and a third LED chip, the first LED chip being configured to provide a first peak wavelength in the range of 430 nanometers (nm) to 480 nm, the second LED chip being configured to provide a second peak wavelength in the range of 500 nm to 570 nm, and the third LED chip being configured to provide a third peak wavelength in the range of 600 nm to 700 nm.

15. The LED device according to claim 1, wherein, The internal mixing chamber is one of a plurality of internal mixing chambers stacked within the support element.

16. An LED device, comprising: One or more LED chips; And A support element, on which the one or more LED chips are mounted, wherein the support element is configured to be light-transmissive for the wavelength of light generated by the one or more LED chips, and the support element includes a light-transmissive layer located between a first light-modulating layer and a second light-modulating layer.

17. The LED device according to claim 16, wherein, The first light-modulating layer is closer to the one or more LED chips than the second light-modulating layer.

18. The LED device according to claim 17, wherein, The first light-modulating layer includes a first light-reflecting layer, and the second light-modulating layer includes a second light-reflecting layer, wherein the first light-reflecting layer has a different reflectivity for the peak wavelength of light from the one or more LED chips than the second light-reflecting layer.

19. The LED device according to claim 17, wherein, The first light modulation layer includes a first light diffusing layer, and the second light modulation layer includes a second light diffusing layer, wherein the first light diffusing layer and the second light diffusing layer diffuse light from the one or more LED chips differently.

20. The LED device according to claim 17, wherein, One of the first light modulation layer and the second light modulation layer includes a light reflecting layer, and the other of the first light modulation layer and the second light modulation layer includes a light diffusing layer.

21. The LED device according to claim 16, wherein, One or more of the first light modulation layer and the second light modulation layer include air pores dispersed in a host material.

22. The LED device according to claim 16, wherein, One or more of the first light modulation layer and the second light modulation layer include oxide particles dispersed in a host material.

23. The LED device according to claim 16, wherein, The light transmissive layer forms an internal light mixing chamber defined by the first light modulation layer and the second light modulation layer.

24. The LED device according to claim 23, wherein, The internal mixing chamber is one of a plurality of internal mixing chambers stacked within the support element.

25. The LED device according to claim 16, wherein, The one or more LED chips include a first LED chip, a second LED chip, and a third LED chip, the first LED chip being configured to provide a first peak wavelength in the range of 430 nanometers (nm) to 480 nm, the second LED chip being configured to provide a second peak wavelength in the range of 500 nm to 570 nm, and the third LED chip being configured to provide a third peak wavelength in the range of 600 nm to 700 nm.

26. The LED device according to claim 16, wherein, At least one of the first light modulation layer and the second light modulation layer includes a multi-layer structure.

27. A light emitting diode (LED) device, comprising: One or more LED chips; A light transmissive layer located on the one or more LED chips; And A light modulation layer, the light modulation layer being arranged in a pattern on the light transmissive layer such that the light transmissive layer is located between the light modulation layer and the one or more LED chips.

28. The LED device according to claim 27, wherein, The light modulation layer includes one or more of a light diffusing layer, a light scattering layer, and a light reflecting layer.

29. The LED device according to claim 28, wherein, The light modulation layer includes the light diffusing layer, and wherein the light diffusing layer includes a textured surface or light diffusing particles dispersed in a light transmissive material.

30. The LED device according to claim 28, wherein, The light modulation layer includes the light reflecting layer, and wherein the light reflecting layer has a thickness less than or equal to 100 nanometers (nm).

31. The LED device according to claim 28, further comprising a light absorption layer located on the light modulation layer and on a part of the light transmissive layer, the part of the light transmissive layer being located between parts of the light modulation layer.

32. The LED device according to claim 27, wherein, The pattern includes discontinuous blocks of the light modulation layer.

33. The LED device according to claim 27, wherein, The pattern includes connected blocks of the light modulation layer.

34. The LED device according to claim 27, wherein, The pattern includes blocks of the light modulation layer aligned with the one or more LED chips.

35. The LED device according to claim 27, wherein, The one or more LED chips include a first LED chip, a second LED chip, and a third LED chip, the first LED chip being configured to provide a first peak wavelength in the range of 430 nanometers (nm) to 480 nm, the second LED chip being configured to provide a second peak wavelength in the range of 500 nm to 570 nm, and the third LED chip being configured to provide a third peak wavelength in the range of 600 nm to 750 nm.

36. The LED device according to claim 27, further comprising a substrate structure, on which one or more LED chips are mounted, wherein,The substrate structure includes a lead frame structure or an insulating base having conductive traces.

37. The LED device according to claim 27, wherein, The light modulation layer includes at least one anodized metal layer.

38. The LED device according to claim 37, further comprising a current diffusion layer located between the at least one anodized metal layer and the one or more LED chips.

39. The LED device according to claim 37, wherein, The at least one anodized metal layer includes a light-absorbing colorant.

40. The LED device according to claim 37, wherein, The at least one anodized metal layer includes local regions having different thicknesses from each other.

41. The LED device according to claim 27, wherein, The pattern is a molded pattern or an embossed pattern.

42. The LED device according to claim 27, wherein, The pattern includes individual features having dimensions in the range of 10 nm to 900 nm.

43. A light emitting diode (LED) device, comprising: One or more LED chips; A first light modulating layer located on the one or more LED chips; A second light modulating layer located on the first light modulating layer such that the first light modulating layer is closer to the one or more LED chips than the second light modulating layer; And A light transmissive layer located between the first light modulating layer and the second light modulating layer, and at least one of the first light modulating layer and the second light modulating layer is arranged in a pattern on the light transmissive layer.

44. The LED device according to claim 43, wherein, Each of the first light modulating layer and the second light modulating layer includes a light diffusing layer or a light reflecting layer.

45. The LED device according to claim 43, wherein, The pattern includes one or more blocks of the second light modulating layer.

46. The LED device according to claim 45, wherein, The first light modulating layer is arranged in an additional pattern, the additional pattern including one or more blocks of the first light modulating layer.

47. The LED device according to claim 46, wherein, One or more blocks of the first light modulating layer are laterally spaced apart from the one or more LED chips to form openings in the first light modulating layer that are aligned with the one or more LED chips.

48. The LED device according to claim 46, wherein, One or more blocks of the first light modulating layer are arranged between the one or more LED chips and the light transmissive layer such that the one or more blocks of the first light modulating layer are aligned with the one or more LED chips.

49. The LED device according to claim 46, wherein, One or more blocks of the first light modulating layer are arranged in a pattern complementary to the one or more blocks of the second light modulating layer.

50. The LED device according to claim 46, wherein, One or more blocks of the first light modulating layer are arranged in the same pattern as the one or more blocks of the second light modulating layer.

51. The LED device according to claim 45, wherein, One or more blocks of the second light modulating layer form a checkerboard pattern.

52. The LED device according to claim 45, wherein, One or more blocks of the second light modulating layer include alternating blocks that vary in surface area or shape.

53. The LED device according to claim 45, wherein, One or more blocks of the second light modulating layer include a first block arranged above the one or more LED chips and a plurality of second blocks arranged around the perimeter of the first block.

54. The LED device according to claim 45, wherein, One or more blocks of the second light modulating layer include a plurality of blocks having a varying density over the LED device.

55. The LED device according to claim 43, wherein, At least one of the first light modulating layer and the second light modulating layer includes an anodized metal layer.

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