Lenses for light emitting diode packages formed by additive manufacturing

Abstract

Light emitting diodes (LEDs) are disclosed, and more specifically, lenses for LED packages formed by additive manufacturing are disclosed. Additive manufacturing is used to solidify precursor material for the lens in a step-wise fashion away from a corresponding submount. The step-wise solidification of the precursor material can be done in a layer-by-layer fashion or in a continuous fashion. This additive manufacturing allows for complex lens shapes of the primary optic and the packaging of the LED chips of the LED package to be formed. Complex shapes include cavities of air or other material embedded within the lens material, cavities formed around the LED chips, gradually increasing lens width, Fresnel shapes, and / or asymmetric shapes, among others.

Description

Technical Field

[0001] This disclosure relates to light-emitting diodes (LEDs), and more specifically, to lenses for LED packages formed by additive manufacturing. Background Technology

[0002] Solid-state lighting devices, such as light-emitting diodes (LEDs), are increasingly used in consumer and commercial applications. LEDs are widely used in a variety of lighting environments, as well as for backlighting liquid crystal displays and for providing sequential lighting in LED displays. Lighting applications include automotive headlights, streetlights, stadium lights, luminaires, flashlights, and a wide range of indoor, outdoor, and special lighting environments. Ideal characteristics of LED devices for various end uses include high luminous efficiency, uniform color distribution over the illuminated area, long lifespan, wide color gamut, and compact size.

[0003] LEDs are solid-state devices that convert electrical energy into light and typically comprise 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 to the doped layers, holes and electrons are injected into one or more active layers, where they recombine to produce emission, such as visible or ultraviolet light. LED chips typically include active regions, which may be made of silicon carbide, gallium nitride, gallium phosphide, indium phosphide, aluminum nitride, gallium arsenide-based materials, and / or organic semiconductor materials. Photons generated in the active regions are emitted in all directions.

[0004] LED packages typically include integrated primary optics that shape the LED chip emission into the desired emission profile of the LED package. Secondary optics, such as secondary lenses and / or reflectors, are sometimes used with the LED package to further guide the desired output beam characteristics. However, secondary optics can increase the size, cost, and complexity of the lighting device and may introduce some optical losses. Another limitation associated with LED lighting devices is, for example, the cost and complexity of manufacturing secondary optics. This limitation becomes more pronounced when manufacturing large quantities of secondary optics with the desired shape or size.

[0005] Existing technologies continue to seek improved LED and solid-state lighting devices with desired lighting characteristics that can overcome the challenges associated with conventional lighting devices. Summary of the Invention

[0006] This disclosure relates to light-emitting diodes (LEDs), and more specifically, to lenses formed by additive manufacturing for LED packages. Additive manufacturing involves progressively curing a precursor material for the lens in a direction away from the corresponding substrate. The progressive curing of the precursor material can be performed layer-by-layer or continuously. This additive manufacturing allows for the formation of complex lens shapes for primary optics and the encapsulation of LED chips in LED packages. Complex shapes include cavities of air or other material embedded within the lens material, cavities formed around the LED chip, progressively increasing lens widths, Fresnel shapes, and / or asymmetrical shapes, etc.

[0007] In one aspect, the LED package includes: a support structure; an LED chip on the support structure; and a lens, on the support structure, the lens forming a package for the LED chip, the lens forming a pocket completely embedded within a continuous material of the lens, and the pocket forming a refractive index step with the continuous material of the lens. In some embodiments, the longest dimension of the pocket is in the range of 25 micrometers (µm) to 4000 µm. In some embodiments, the pocket forms an ellipsoidal shape within the lens. In some embodiments, the pocket forms an air cavity within the lens. In some embodiments, the pocket holds a filling material different from the continuous material of the lens. In some embodiments, the lens forms a base on the support structure and a top spaced apart from the support structure by the base, the base having a width that increases with distance from the support structure. In some embodiments, the top surface of the top of the lens forms a Fresnel lens. In some embodiments, the pocket is a first pocket and the lens also forms a second pocket embedded within the continuous material of the lens. In some embodiments, the cavity is one of a cavity array in which a periodic array is formed within a continuous material of the lens. In some embodiments, the lens has an asymmetrical shape relative to the abutment.

[0008] In another embodiment, the LED package includes: a support structure; an LED chip on the support structure; and a lens formed directly on the support structure, the lens forming a cavity on the support structure that separates the LED chip from the lens material. In some embodiments, the cavity is formed in a semi-ellipsoidal shape surrounding the LED chip. In some embodiments, the cavity is formed in a cuboid shape. In some embodiments, the cavity forms an air cavity surrounding the LED chip. In some embodiments, the cavity retains a filling material different from the material of the lens.

[0009] In another aspect, a method of manufacturing an LED package includes: providing a substrate on which an LED chip is mounted; and forming a lens on the substrate and the LED chip by additive manufacturing, the additive manufacturing including progressively curing a precursor material for the lens in a direction away from the substrate. In some embodiments, progressively curing the precursor material includes progressively curing a progressive layer of the precursor material in a direction away from the substrate. In some embodiments, progressively curing the precursor material includes continuously curing the precursor material in a direction away from the substrate. The method may also include forming a cavity in the lens, the cavity comprising air or a filling material that is a different material from the lens. In some embodiments, the substrate and the LED chip are part of an LED panel, and multiple lenses are formed by progressively curing the precursor material for the lens in a direction away from the substrate.

[0010] On the other hand, any of the foregoing aspects, individually or together, and / or the different individual aspects and features as described herein, may be combined for additional advantages. Unless otherwise stated herein, any of the various features and elements disclosed herein may be combined with one or more other disclosed features and elements.

[0011] After reading the following detailed description of preferred embodiments in conjunction with the accompanying drawings, those skilled in the art will understand the scope of this disclosure and implement its additional aspects. Attached Figure Description

[0012] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several aspects of this disclosure and, together with the embodiments, serve to explain the principles of this disclosure.

[0013] Figure 1A A simplified cross-sectional view of an exemplary light-emitting diode (LED) package is shown. The LED chip is encapsulated by a lens forming an integrated primary optical device.

[0014] Figure 1B A top view of an LED panel having a plurality of LED packages from FIG1 formed on the top surface of a panel or base, according to aspects of the present disclosure.

[0015] Figure 1C This illustration shows multiple LED packages manufactured in accordance with aspects of this disclosure. Figure 1B A cross-sectional view of a portion of the LED panel.

[0016] Figure 2 A conventional manufacturing method for lenses and LED packages used in the manufacture of LED panels is shown.

[0017] Figure 3A The image shows a base after the first cured layer of a lens has been formed using a layer-by-layer additive printing method, according to aspects of this disclosure.

[0018] Figure 3B This shows what is seen after the second cured layer of the lens is formed using a layer-by-layer additive printing method. Figure 3A The base.

[0019] Figure 3C It shows that in the Figure 3B The steps are repeated a selected number of times to create the lens using a layer-by-layer additive printing method, as seen afterward. Figure 3B The base.

[0020] Figure 3D The formation of the LED panel is shown. Figure 3C The base of the LED panel has multiple LED packages manufactured using methods such as layer-by-layer additive printing.

[0021] Figure 4 Description shown Figures 3A to 3D An exemplary process flow diagram of the general manufacturing steps of the layer-by-layer additive printing method.

[0022] Figure 5A The substrate is shown in the manufacturing step after the first cured layer of the lens is formed using an injection printing method, according to aspects of this disclosure.

[0023] Figure 5B This shows what is seen after the second cured layer of the lens is formed using an injection printing method. Figure 5A The base.

[0024] Figure 5C It shows that in the Figure 5B The steps are repeated a selected number of times to create the lens using the injection printing method, as seen afterward. Figure 5B The base.

[0025] Figure 5D The formation of the LED panel is shown. Figure 5C The base of the LED panel has multiple LED packages formed using an injection printing method.

[0026] Figure 6 Description is shown Figures 5A to 5D An exemplary process flow diagram of the general manufacturing steps of the injection printing method.

[0027] Figure 7A The image shows a base after the first cured layer of a lens is fabricated during additive digital light processing (DLP) according to aspects of this disclosure.

[0028] Figure 7B This shows the process after the formation of the second cured lens layer. Figure 7A The base is used as part of the subsequent manufacturing steps of the additive DLP method.

[0029] Figure 7C It shows that Figure 7B The manufacturing process is repeated a selected number of times to complete the manufacturing of the lens.

[0030] Figure 8 Description is shown Figures 7A to 7C An exemplary process flow diagram of the general manufacturing steps of the additive DLP method.

[0031] Figure 9A A pedestal for forming a first grating layer of a lens is shown in a stereolithography (SLA) printing method according to aspects of the present disclosure, positioned relative to a resin bath.

[0032] Figure 9B This shows the process after the formation of the second grating lens layer. Figure 9A The base, as part of the layer-by-layer SLA printing method.

[0033] Figure 9C It shows how to... Figure 9B The manufacturing steps shown are repeated a selected number of times to manufacture the lens as part of a layer-by-layer SLA printing method.

[0034] Figure 10 Description is shown Figures 9A to 9C An exemplary process flow diagram of the general manufacturing steps of the layer-by-layer SLA printing method.

[0035] Figure 11A A substrate with an LED chip is shown according to an aspect of this disclosure, the LED chip being positioned to form a lens by an additive liquid crystal display (LCD) printing method.

[0036] Figure 11B The substrate is shown after the formation of another LCD curing layer, as part of a subsequent manufacturing step in the additive LCD printing method.

[0037] Figure 11C It shows that Figure 11B The manufacturing process is repeated a selected number of times to complete the manufacturing of the lens.

[0038] Figure 12 Description is shown Figures 11A to 11C An exemplary process flow diagram of the general manufacturing steps of the LCD printing method.

[0039] Figure 13 This is a perspective view of an LED package having a lens with a cavity formed inside the lens, based on the principles of this disclosure.

[0040] Figure 14 Is with Figure 13The image shows a three-dimensional view of an LED package similar to the one shown, except that the cavity in the lens is formed into a semi-ellipsoidal shape.

[0041] Figure 15 Is with Figure 13 This is a 3D view of an LED package similar to the one shown, except that the cavity is formed close to the base.

[0042] Figure 16 Is with Figure 13 The image shows a three-dimensional view of an LED package similar to the one shown, except that the top surface of the lens is formed with a Fresnel lens.

[0043] Figure 17 Is with Figure 15 This is a 3D view of a similar LED package, except that the rectangular cavity is formed near the base.

[0044] Figure 18 This is for an implementation of a lens with a generally curved shape. Figure 13 A 3D view of an LED package similar to the LED package.

[0045] Figure 19 This is for implementations with multiple cavities. Figure 18 A 3D view of an LED package similar to the LED package.

[0046] Figure 20 This is a description of an implementation method where multiple cavities form a periodic array within a lens. Figure 19 A 3D view of an LED package similar to the LED package.

[0047] Figure 21 This refers to embodiments that include multiple cavities with an ellipsoidal shape. Figure 19 A 3D view of an LED package similar to the LED package.

[0048] Figure 22 This refers to the implementation method where the cavity forms a non-circular geometry. Figure 13 A 3D view of an LED package similar to the LED package.

[0049] Figure 23 This is for implementation methods of lenses with asymmetrical shapes. Figure 13 A cross-sectional view of an LED package similar to the LED package. Detailed Implementation

[0050] The embodiments described below provide the necessary information to enable those skilled in the art to practice the embodiments and illustrate the best mode of practice. When reading the following description in conjunction with the accompanying drawings, those skilled in the art will understand the concepts of this disclosure and will recognize that these concepts do not specifically address any applications herein. It should be understood that these concepts and applications fall within the scope of this disclosure and the appended claims.

[0051] It will be understood that while 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 used only to distinguish one element from another. For example, without departing from the scope of this disclosure, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0052] It will be understood that when an element, such as a layer, region, or substrate, is referred to as being "on" or extending "on" another element, the element may be directly on or directly extending onto the other element, or intermediate elements may be present. Conversely, when an element is referred to as being "directly on" or "directly extending onto" another element, no intermediate elements are present. Similarly, it will be understood that when an element, such as a layer, region, or substrate, is referred to as being "on" or extending "on" another element, the element may be directly on or directly extending onto the other element, or intermediate elements may be present. Conversely, when an element is referred to as being "directly on" or "directly extending onto" another element, no intermediate elements are present. It should also be understood that when an element is referred to as being "connected" or "attached" to another element, the element may be directly connected or attached to the other element, or intermediate elements may be present. Conversely, when an element is referred to as being "directly connected" or "directly attached" to another element, no intermediate elements are present.

[0053] Relative terms such as “below” or “above” or “upper” or “lower” or “horizontal” or “vertical” may be used herein to describe the relationship between one element, layer, or region and another element, layer, or region as shown. It will be understood that these terms, and those mentioned above, are intended to include different orientations of the device other than those depicted in the figures.

[0054] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. As used herein, unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well. It should be further understood that, when used herein, the terms “comprises,” “comprising,” “includes,” and / or “including” specify the presence of the stated feature, integral, step, operation, element, and / or component, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or combinations thereof.

[0055] Unless otherwise defined, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. It should be further understood that the terms used herein shall be interpreted as having the same meaning as they have in the context of this specification and the relevant field, and shall not be interpreted in an idealized or overly formal sense unless expressly defined herein.

[0056] Embodiments are described herein with reference to schematic diagrams illustrating embodiments of this disclosure. Therefore, the actual dimensions of layers and elements may vary, and variations in shape from the illustrations are anticipated, for example, due to manufacturing techniques and / or tolerances. For instance, areas illustrated or described as squares or rectangles may have circular or curved features, and areas shown as straight lines may have some irregularity. Therefore, the areas shown in the figures are schematic, and their shapes are not intended to show the precise shapes of areas of the device, nor are they intended to limit the scope of this disclosure. Furthermore, for illustrative purposes, the dimensions of structures or areas may be enlarged relative to other structures or areas; thus, these dimensions or areas are provided to illustrate the general structure of the subject matter and may or may not be drawn to scale. Common elements between the figures may be indicated herein by common element numbers and may not be described further thereafter.

[0057] This disclosure relates to light-emitting diodes (LEDs), and more specifically, to lenses formed by additive manufacturing for LED packages. Additive manufacturing is used to progressively cure a precursor material for the lens in a direction away from the corresponding substrate. The progressive curing of the precursor material can be performed layer-by-layer or continuously. This additive manufacturing allows for the formation of complex lens shapes for primary optics and packages of LED chips for LED packages. Complex shapes include cavities of air or other materials embedded within the lens material, cavities formed around the LED chip, progressively increasing lens widths, Fresnel shapes, and / or asymmetrical shapes, etc.

[0058] Before exploring the specific details of the various aspects of this disclosure, an overview of various elements that may be included in the exemplary LED packages of this disclosure is provided for context. LED chips typically include active LED structures or regions that may have many different semiconductor layers arranged in different ways. The fabrication and operation of LEDs and their active structures are well known in the art and are only briefly discussed herein. The layers of an active LED structure can be fabricated using known processes, with metal-organic chemical vapor deposition being a suitable process. The layers of an active LED structure may include many different layers and typically include an active layer sandwiched between opposing n-type doped epitaxial layers and p-type doped epitaxial layers, all of which are formed continuously on a growth substrate. It should be understood that active layers and elements may 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 layers and light extraction layers and elements. Active layers may include single quantum wells, multiple quantum wells, dual heterostructures, or superlattice structures.

[0059] Active LED structures can be made from various material systems, some of which are based on group 11I nitrides. Other material systems include organic semiconductor materials and group 11I-V systems, such as gallium phosphide (GaP), gallium arsenide (GaAs), indium phosphide (InP), and related compounds. Different implementations of active LED structures can emit light of different wavelengths depending on the material system used.

[0060] In some embodiments, the active LED structure emits blue light with a peak wavelength range in the range of 430 nanometers (nm) to 480 nm. In other embodiments, the active LED structure emits green light with a peak wavelength range in the range of 500 nm to 570 nm. In other embodiments, the active LED structure emits orange and / or red light with a peak wavelength range in the range of 600 nm to 700 nm. In still other embodiments, the active LED structure may emit cyan light with a peak wavelength range in the range of 485 nm to 500 nm or violet light with a peak wavelength range in the range of 400 nm to 420 nm. In some embodiments, the active LED structure may be configured to emit light outside the visible spectrum, including one or more portions of the ultraviolet (UV) spectrum, infrared (IR) spectrum, or near-IR spectrum. The UV spectrum is typically divided into three wavelength range categories denoted by the letters A, B, and C. In this manner, UV-A light is typically defined as having a peak wavelength range from 315 nm to 400 nm, UV-B as having a peak wavelength range from 280 nm to 315 nm, and UV-C as having a peak wavelength range from 100 nm to 280 nm. UV LEDs are of particular interest for applications involving the disinfection of microorganisms (among other things) in air, water, and surfaces. In other applications, UV LEDs may also be provided with one or more luminescent materials to provide focused emission with broad spectrum and improved color quality for visible light applications. The near-IR and / or IR wavelengths of the LED structures disclosed herein may have wavelengths higher than 700 nm, such as in the range of 700 nm to 1000 nm or greater.

[0061] As used herein, a layer or region of a light-emitting device may be considered "transparent" when at least 80% of the emitted radiation illuminating that layer or region passes through that layer or region. Furthermore, as used herein, a layer or region of an LED may be considered "reflective" or embodied as a "mirror" or "reflector" when at least 80% of the emitted radiation illuminating that layer or region is reflected. In some embodiments, the emitted radiation includes visible light, such as in blue and / or green LEDs with or without a light-emitting 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, suitable materials may be selected to provide the desired, and in some embodiments, high reflectivity and / or the desired, and in some embodiments, low absorption. In some embodiments, a "transparent" material may be configured to transmit at least 50% of the emitted radiation of the desired wavelength.

[0062] This disclosure applies to LED chips having various geometries, such as vertical or lateral geometries. LED chips with vertical geometries typically include anode and cathode connections on opposite sides or faces of the LED chip. LED chips with lateral geometries typically include anode and cathode connections on the same side of the LED chip opposite a substrate (such as a growth substrate). In some embodiments, the lateral geometry LED chip may be mounted on a substrate of an LED package such that the anode and cathode connections are on the face of the LED chip opposite the substrate. In this configuration, wire bonding may be used to provide electrical connections to the anode and cathode connections. In other embodiments, the lateral geometry LED chip may be flip-chip mounted on the surface of a substrate of an LED package such that the anode and cathode connections are on the face of the active LED structure adjacent to the substrate. In this configuration, traces or patterns may be provided on the substrate to provide electrical connections to the anode and cathode connections of the LED chip. In a flip-chip configuration, the active LED structure is disposed between the substrate of the LED chip and the substrate for the LED package. Thus, light emitted from the active LED structure can pass through the substrate in a desired emission direction. In other embodiments, the active LED structure can be attached to a carrier substrate and the growth substrate can be removed so that light can exit the active LED structure without passing through the growth substrate.

[0063] An LED package may include one or more elements (such as luminescent materials and electrical contacts) on which one or more LED chips are disposed on a support member (such as a base or lead frame). Suitable materials for the base include, but are not limited to, ceramic materials such as alumina or aluminum oxide, AlN, or organic insulators such as polyimide (PI) and polyphthalamide (PPA). The base may also include a printed circuit board (PCB), sapphire, Si, or any other suitable material. For PCB implementations, different PCB types may be used, such as standard FR-4 PCB, metal-core PCB, or any other type of PCB. In a further embodiment, the support structure may be embodied as a lead frame structure having a lead frame and a corresponding housing positioned around a portion of the lead frame. Light-changing materials may be arranged within the LED package to reflect or otherwise redirect light from one or more LED chips in a desired emission direction or pattern.

[0064] As used herein, "light-modifying material" can include many different materials, including light-reflecting materials that reflect or redirect light, light-scattering materials that absorb light, light-emitting materials, and materials that act as thixotropic agents. As used herein, the term "light-reflecting" refers to a material or particle that reflects, refracts, scatters, or otherwise redirects light. For light-reflecting materials, light-modifying materials can include at least one of fused silica, pyrolytic silica, titanium dioxide (TiO2), or metal particles suspended in a binder (e.g., silicone or epoxy resin). In some aspects, these particles may have one or more refractive indices configured to refract light emission in a desired direction. In some aspects, light-reflecting particles may also be referred to as light-scattering particles. For light-absorbing materials, light-modifying materials can include at least one of carbon, silicon, or metal particles suspended in a binder (e.g., silicone or epoxy resin). Light-reflecting and light-absorbing materials can include nanoparticles. In some embodiments, light-modifying materials can include generally white materials to reflect and redirect light. In other embodiments, light-modifying materials can include generally opaque colors, such as black or gray for absorbing light and increasing contrast. In some embodiments, the light-changing material includes both light-reflecting and light-absorbing materials suspended in the adhesive.

[0065] This disclosure relates to solid-state light-emitting devices and related methods, such as LED packages incorporating lens structures arranged on one or more solid-state light emitters (e.g., LED chips). Conventional primary optics in LED packages are typically formed from a package material for the LED chip. The LED chip can be effectively embedded within the package material, and the corresponding shape of the package material is designed to provide a desired emission profile. Conventional techniques for forming primary optics include molding a material such as silicone onto an LED package substrate using a molding block. While there is some ability to change the shape of the lens by altering the molding block, the types and shapes of lenses that can be manufactured are limited by the ability to remove the molding block from the lens without damaging or otherwise altering the lens shape. Some aspects of this disclosure relate to LED packages having integrated lens structures manufactured and fabricated using additive technologies such as three-dimensional (3D) printing. In this regard, more complex structures for primary optics in LED packages can be achieved. Some aspects relate to methods for using precursor materials in additive manufacturing of primary optics integrated within an LED package.

[0066] Figure 1AA simplified cross-sectional view of an exemplary LED package 10 is shown, comprising an LED chip 12 encapsulated by a lens 14 forming an integrated primary optics element. The LED chip 12 is supported and / or mounted on a base 16, and the top surface 12A of the LED chip 12 is positioned to emit light toward the lens 14. According to various embodiments, the base 16 may be separable from a larger panel or sub-assembly for mass production. As shown, the lens 14 forms an integral structure disposed on the top surface 16A of the base 16 to effectively seal the LED chip 12. Emissions from the LED chip 12 are typically emitted or reflected in a direction away from the top surface 16A to exit the lens 14 in a desired emission profile.

[0067] Figure 1B A top view of an LED panel 100 according to aspects of this disclosure, having a plurality of LED packages 10 from FIG1 formed on the top surface 16A of a panel or base 16, is shown. Figure 1B In the middle, the base 16 forms part of the larger LED panel 100 and its portion will be divided to form Figure 1A LED package 10.

[0068] Figure 1C The illustration shows a plurality of LED packages 10 manufactured according to aspects of this disclosure. Figure 1B A cross-sectional view of a portion of the LED panel 100. (See previous reference.) Figure 1B The LED panel 100 includes a base 16 having a top surface 16A. LED chips 12 are disposed above the top surface 16A, and a single LED chip 12 or a combination of multiple LED chips 12 is encapsulated by one or more lenses 14.

[0069] In this regard, providing Figures 1A to 1C This is to facilitate the description of various structures and manufacturing processes for lenses, LED packages, and LED panels utilizing additive manufacturing as described herein. Figures 1A to 1C The lens 14, LED package 10, and LED panel 100 shown and described herein are provided as exemplary structures. Various embodiments of this disclosure are applicable to any size, shape, quantity, type, position, orientation, etc., of the lens, LED package, and corresponding LED panel.

[0070] Figure 2 A standard manufacturing method is shown for a lens 214 and an LED package 210 used in the manufacture of an LED panel 200. (Reference) Figure 2Typically, a plurality of casting molds 218A of the molding block 218 are filled with a curable resin precursor solution 220 (hereinafter referred to as precursor solution 220), which may be, for example, a curable silicone solution. Next, the top surface 216A of the base 216 of the LED panel 200 is positioned above the molding block 218. The top surface 216A is then brought into contact with the molding block 218, such that the LED chip 212 on the top surface 216A is positioned within the corresponding casting mold 218A now filled with the precursor solution 220. After curing, the molding block 218 is released, resulting in the LED panel 200 having the LED chip 212 encapsulated within a lens 214. Care should be taken to minimize damage to the lens 214 when it is released from the casting mold 218A. Furthermore, the structure and shape of the lens 214 may be limited by some shape constraints required for releasing the lens 214 from the casting mold 218A. For example, it may be difficult to achieve lenses with complex geometries using conventional molding methods.

[0071] Figures 3A to 3D The various steps of a layer-by-layer additive printing method for fabricating a lens 314 on an LED chip 312 of an LED package 310 of a corresponding LED panel 300, according to the principles of this disclosure, are illustrated. The layer-by-layer additive printing method may include raster scanning a focused UV beam 334 generated by a UV laser device 332 onto a UV-curable resin precursor solution 320 (hereinafter referred to as precursor solution 320), selectively curing predetermined areas of the precursor solution 320 in a continuous and layer-by-layer manner according to a corresponding raster pattern in the raster pattern 330.

[0072] Figure 3A The image shows a base 316 or base panel after the first cured layer of lens 338-1 has been formed using a layer-by-layer additive printing method. Figure 3A The manufacturing steps are generally illustrated, which involve placing a base 316 in a resin tank 328, providing a precursor solution 320 to the resin tank 328 to uniformly cover the top surface 316A of the base 316 with a first precursor solution layer 336-1, and grating scanning a focused UV beam 334 according to a first grating pattern 330-1 to cure a predetermined area of ​​the precursor solution 320 and form a first cured layer of lens 338-1. As shown, once the precursor solution 320 is added to the resin tank 328, the first precursor solution layer 336-1 is formed with a first thickness T. PS1The precursor solution 320 is formed above the top surface 316A of the substrate 316. It can be a UV-curable silicone solution, acrylate, epoxy resin, etc. Next, a UV laser device 332 generates a focused UV beam 334 and irradiates a predetermined area of ​​the first precursor solution layer 336-1 designated by the first grating pattern 330-1 to form the first cured layer of the lens 338-1. The first grating pattern 330-1 can be a pixel matrix providing a two-dimensional (2D) map of the area of ​​the first precursor solution layer 336-1, which is illuminated and cured above the top surface 316A of the substrate 316 to at least partially form the first cured layer of the lens 338-1 above and on each LED chip 312 of the substrate 316.

[0073] After the formation of the first cured layer of lens 338-1, the stage 316 is optionally removed from the resin tank 328, and one or more optional post-processing procedures are subsequently performed to improve the transparency, structural integrity, uniformity, mechanical properties, and / or other properties of the first cured layer of lens 338-1. In this regard, one or more post-processing procedures may include high-temperature treatment, high-pressure treatment, vacuum drying, freeze drying, UV irradiation, surface treatment, etc.

[0074] Figure 3B The base 316 is shown after the second cured layer of lens 338-2 is formed using a layer-by-layer additive printing method. Figure 3B The following manufacturing steps are generally shown for curing a second cured layer of lens 338-2 by irradiating a predetermined area of ​​the second precursor solution layer 336-2 with a focused UV beam 334.

[0075] After completion Figure 3A Following the manufacturing steps shown, an additional amount of precursor solution 320 is added to resin tank 328 to form a second precursor solution layer 336-2 above the top surface of the first cured layer of lens 338-1. In application, the precursor solutions 320 corresponding to the first precursor solution layer 336-1 and the second precursor solution layer 336-2 are mixed with each other and are therefore indistinguishable. In this respect, the first precursor solution layer 336-1 and the second precursor solution layer 336-2 can be distinguished from each other based on an imaginary plane parallel to and above the top surface 316A of the abutment 316. In this respect, the first imaginary plane can be formed above the top surface 316A of the abutment 316, the top surface 316A having a first thickness T corresponding to the first precursor solution layer 336-1. PS1 The height. Furthermore, a second imaginary plane may be formed above the top surface of the first precursor solution layer 336-1, the first precursor solution layer 336-1 having a second thickness T corresponding to the second precursor solution layer 336-2. PS2 The height.

[0076] During the formation of the second precursor solution layer 336-2, a focused UV beam 334 generated by the UV laser device 332 is used to expose a predetermined area of ​​the second precursor solution layer 336-2 according to the second grating pattern 330-2, such that the lens 338-2 of the second cured layer is at least partially formed on, around and / or on the lens 338-1 of the first cured layer.

[0077] In some embodiments, the focused UV beam 334 may extend further into the first precursor solution layer 336-1 to expose and cure predetermined areas adjacent to the first precursor solution layer 336-1 and the second precursor solution layer 336-2. In this way, an interlocking solid structure can be formed between adjacent and connected layers, such as the first cured layer of lens 338-1 and the second cured layer of lens 338-2, which form part of lens 314. This is particularly advantageous because it further enhances the integrity, transparency, and quality of lens 314 manufactured using a layer-by-layer additive printing method.

[0078] Figure 3C This demonstrates the use of a layer-by-layer additive printing method to... Figure 3B The steps are repeated a selected number of times N to manufacture the base 316 as seen after lens 314. In this regard, Figure 3C It roughly shows the method used to... Figure 3B The manufacturing steps are repeated a selected number of times N to manufacture the subsequent manufacturing steps of the LED panel 300 with lens 314.

[0079] In this manner, an additional amount of precursor solution 320 is added to resin tank 328 to provide the i-th precursor solution layer 336-i (where i is a number and 2 < i ≤ N). Next, according to the i-th grating pattern 330-i, a focused UV beam 334 is used to expose a predetermined area of ​​the i-th precursor solution layer 336-i. In this manner, the i-th cured lens layer 338-i is formed at least partially above, around, and / or on top of the previously cured lens layer. Once... Figure 3B The process outlined in the document (or Figure 4 Step 402) is repeated N times, and a lens 314 for encapsulating the LED chip 312 is formed above the top surface 316A of the substrate 316. In this way, an LED package 310 forming part of the LED panel 300 is manufactured.

[0080] Figure 3D An LED panel 300 is shown having multiple LED packages 310 manufactured using a layer-by-layer additive manufacturing method, and as shown after removal from the resin tank 328. In this regard, Figure 3DThis corresponds to any optional post-processing manufacturing steps for removing any remaining precursor solution 320 from the resin tank 328, removing the LED panel 300 from the resin tank 328, and the LED panel 300. Figure 4 (404). Then, a splitting or cutting step can be performed to separate the individual LED packages in the LED package 310 from the LED panel 300.

[0081] Figure 4 Description shown Figures 3A to 3D An exemplary process flow diagram 400 illustrates the general manufacturing steps of a layer-by-layer additive printing method. Figure 4 In the middle, step 401 roughly corresponds to Figure 3A This is used to place the stage 316 in the resin tank 328, provide the precursor solution 320 to the resin tank 328 to uniformly cover the top surface 316A of the stage 316 with a first precursor solution layer 336-1, and scan a focused UV beam 334 according to the first grating pattern 330-1 to cure a predetermined area of ​​the precursor solution 320 and form a first cured layer of the lens 338-1. Step 402 generally corresponds to Figure 3B This is used to irradiate a predetermined area of ​​the second precursor solution layer 336-2 with a focused UV beam 334 to cure and form the second cured layer of the lens 338-2. Step 402 generally corresponds to Figure 3C This is used to repeat step 402 N times to manufacture the LED panel 300 with lens 314. Step 404 roughly corresponds to... Figure 3D Used for removing any remaining precursor solution 320 from resin tank 328, removing LED panel 300 from resin tank 328, and any optional post-processing of LED panel 300.

[0082] Figures 5A to 5D This paper describes an injection printing method for manufacturing lenses 514 and LED packages 510 for an LED panel 500. As will be discussed in more detail herein, the injection printing method involves extruding and depositing a precursor solution 520 onto the top surface 516A of a substrate 516 using an extrusion nozzle 546 at a controlled speed and a predetermined output rate. In this regard, a substrate 516 having one or more LED chips 512 is first placed within a UV chamber 540, and then the precursor solution 520 is deposited in a continuous manner over a predetermined area, as shown in the corresponding layer layout 542. The precursor solution 520 is cured by UV light 524 generated by a UV source 522 of the UV chamber 540 as it is deposited above, around, and over the LED chips 512 on the substrate 516, forming multiple lenses 514, and thus forming the LED package 510 as part of the LED panel 500. Although in Figures 5A to 5DIt is provided in the context of forming an array of lenses 514, but the described principle also applies to forming one lens 514 at a time.

[0083] Figure 5A The image shows the base 516 in a manufacturing step following the formation of the first cured layer of lens 538-1 using an injection printing method. In this regard, Figure 5A The diagram generally shows a stage 516 placed in a UV chamber 540 and a precursor solution 520 introduced over a selected portion of the top surface 516A of the stage 516 using an extrusion nozzle 546, such that the precursor solution 520 is cured by UV light 524 to form a first cured layer of the lens 538-1.

[0084] The UV chamber 540 is configured to expose the area above and over the top surface 516A of the base 516 using UV light 524 generated by one or more UV sources 522. In some embodiments, the UV chamber 540 provides a wide angular distribution of the UV light 524 by using multiple UV sources 522 and / or reflectors (not shown). In this way, the UV light 524 is exposed above and over the top surface 516A of the base 516 in a substantially uniform manner.

[0085] The extrusion nozzle 546 moves above the top surface 516A of the substrate 516 to extrude the precursor solution 520 over a predetermined area of ​​the top surface 516A according to the first layer layout 542-1 of the layer layout 542. In this respect, the first layer layout 542-1 provides a 2D graphic representation of the shape and structure of the first cured layer of the lens 538-1. The extrusion nozzle 546 deposits the precursor solution 520 over the top surface 516A of the substrate 516 at a rate such that the precursor solution 520 is cured by UV light 524 during and after deposition. In this manner, the UV chamber 540 and the UV light 524 therein are used to form the first cured layer of the lens 538-1, which is formed over the top surface 516A of the substrate 516 and at least partially covers the LED chip 512.

[0086] After the first cured layer of lens 538-1 is formed, the substrate 516 can be removed from the UV chamber 540, followed by one or more optional post-processing procedures (not shown) to improve the transparency, structural integrity, uniformity, or other optical or mechanical properties of the first cured layer of lens 538-1, which is part of the lens 514 of LED 510. In this regard, the post-processing procedures may include one or more of the following: high-temperature treatment, high-pressure treatment, vacuum drying, freeze drying, UV irradiation, surface treatment, etc. After the post-processing procedures are completed, the substrate 516 is returned to the UV chamber 540 for further processing.

[0087] Figure 5BThe image shows the abutment 516 as seen after the second cured layer of lens 538-2 has been formed using an injection printing method. In this regard, Figure 5B The precursor solution 520 is introduced at least partially above, around and over the first cured layer of lens 538-1 using an extrusion nozzle 546, such that the precursor solution 520 is cured by UV light 524 to form the second cured layer of lens 538-2.

[0088] In this regard, according to the second layer layout 542-2, a precursor solution 520 is deposited above, around, and over the first cured layer of lens 538-1 using an extrusion nozzle 546. The precursor solution 520 is cured by UV light 524 generated by UV source 522 to form the second cured layer of lens 538-2. In some embodiments, the first cured layer of lens 538-1 and the second cured layer of lens 538-2 form an interlocking and integral structure that becomes part of the lens 514 of LED package 510.

[0089] Figure 5C It shows that in the case of Figure 5B The steps disclosed herein are repeated N times to fabricate the lens 514 using an injection printing method, resulting in the base 516 as seen afterward. In this regard, Figure 5C It shows that Figure 5B The manufacturing steps are repeated N times to manufacture the lens 514 that forms part of the LED package 510 for the LED panel 500.

[0090] After forming the second cured layer of lens 538-2, use extrusion nozzle 546 for reference. Figure 5B The precursor solution 520 is deposited and extruded according to the i-th layer layout 542-i, such that the precursor solution 520 is cured by UV light 524 to form the i-th cured lens layer 538-i. In this way, the lens 514 of the LED package 510 for the LED panel 500 is formed into the desired shape.

[0091] Figure 5D An LED panel 500 with multiple lenses 514 is shown. The lenses 514 are part of an LED package 510 manufactured using an injection printing method and are visible after removal from the UV chamber 540. In this regard, Figure 5D This corresponds to the manufacturing steps for removing the LED panel 500 from the UV chamber 540 and subsequently performing optional post-processing on the lens 514.

[0092] Figure 6 Description is shown Figures 5A to 5D An exemplary process flow diagram 600 illustrates the general manufacturing steps of the injection printing method. Figure 6 In the middle, step 601 roughly corresponds to Figure 5A , Figure 5A The substrate 516 is placed in the UV chamber 540 and a precursor solution 520 is introduced over the top surface 516A of the substrate 516 using an extrusion nozzle 546. According to the first layer layout 542-1, the precursor solution 520 is cured by UV light 524 to form the first cured layer of the lens 538-1. Step 602 generally corresponds to... Figure 5B The precursor solution 520 is deposited, using an extrusion nozzle 546, within a UV chamber 540 and at least partially above, around, and over the first cured layer of lens 538-1 according to a second layer layout 542-2, such that the precursor solution 520 is cured by UV light 542 to form the second cured layer of lens 538-2. Step 603 generally corresponds to... Figure 5C This is used to repeat step 602 a selected number of times N to manufacture an LED panel 500 including an LED package 510 with a lens 514. Step 604 generally corresponds to... Figure 5D It is used to remove the LED panel 500 from the UV chamber 540, followed by optional post-processing of the lens 514.

[0093] Figures 7A to 7C An additive digital light processing (DLP) method for manufacturing a lens 714 for an LED panel 700 and a corresponding LED package 710 is shown. As will be discussed in more detail herein, a resin tank 728 contains a precursor solution 720, and the bottom surface of the resin tank 728 is transparent. Furthermore, a stage 716 is immersed in the precursor solution 720 within the resin tank 728 and remains above the bottom surface of the resin tank 728, with the top surface 716A of the stage 716 facing downwards and toward the bottom surface of the resin tank 728. In this manner, the additive DLP method uses a UV projector 750 or the like to project patterned UV light 752 corresponding to the layer layout 742 onto and through the bottom surface of the resin tank 728 to continuously cure the precursor solution 720 as the stage 716 moves upwards within the precursor solution 720. Thus, a lens 714 is formed for the LED package 710 of the LED panel 700.

[0094] Figure 7A The image shows the abutment 716 after the first cured layer of lens 738-1 has been fabricated during the additive DLP process. In this regard, Figure 7A Corresponding to the provision of precursor solution 720 to resin tank 728 having a transparent bottom surface, a platform 748 is used to hold and move a stage 716 along the Z-axis within the resin tank 728, with the top surface 716A of the stage 716 facing the bottom surface of the resin tank 728, and the stage 716 is lowered within the resin tank 728 to have a predetermined thickness T. PS1A manufacturing step involves holding a first precursor solution layer 736-1 between the top surface 716A of the substrate 716 and the bottom surface of the resin tank 728, and irradiating the first precursor solution layer 736-1 with UV light 752 having a pattern corresponding to the first layer layout 742-1 through the bottom surface of the resin tank 728 using a UV projector 750. In this manner, a first cured layer of the lens 738-1 is cured and formed over the top surface 716A of the substrate 716, and the first cured layer of the lens 738-1 forms part of the lens 714 of the LED package 710. For illustrative purposes, the first cured layer of the lens 738-1 is shown being removed from the resin tank 728. In practice, the substrate 716 may or may not be removed from the resin tank 728 before forming additional cured layers.

[0095] The UV projector 750 is capable of directly generating UV light 752 with a pattern corresponding to each layer layout 742. Alternatively or additionally, patterned masks, digital micromirror devices, or other suitable methods or devices can be used to generate UV light 752 with a pattern corresponding to each layer layout 742.

[0096] Figure 7B This illustrates the process after the formation of the second cured layer of lens 738-2, as part of a subsequent manufacturing step in the additive DLP method. Figure 7A The base 716. In this regard, Figure 7B Corresponding to the use of stage 748 to raise stage 716 within resin tank 728, such that the second precursor solution layer 736-2 is held between the top surface of the first cured layer of lens 738-1 and the bottom surface of resin tank 728, and using UV projector 750 to irradiate the second precursor solution layer 736-2 with UV light 752 having a pattern corresponding to the second layer layout 742-2 through the bottom surface of resin tank 728, the second cured layer of lens 738-2 is cured and formed above and around the first cured layer of lens 738-1. This is particularly advantageous because it provides for the continuous formation of lens 714, which also encapsulates LED chip 712. In some embodiments, UV light 752 having a pattern corresponding to the second layer layout 742-2 can expose the area above the second precursor solution layer 736-2 to cure a predetermined area surrounding the first cured layer of lens 738-1, in order to further interlock adjacent cured layers and enhance the integrity, transparency, and quality of the resulting lens 714. Figure 7A Similarly, in Figure 7B The image shows the base 716 being removed from the resin tank 728 to show the second cured layer of the lens 738-2. In practice, the base 716 may or may not be removed from the resin tank 728 before an additional cured layer is formed.

[0097] Figure 7C It shows that Figure 7B The manufacturing steps are repeated a selected number N of times to complete the manufacture of the lens 714. In Figure 7C , for illustrative purposes, the base 716 is initially shown removed from the resin bath 728. As described above, according to the embodiment, during the entire formation process of the lens 714, the base 716 may or may not remain in the resin bath 728. In some embodiments, the platform 748 is utilized to raise the base 716 within the resin bath 728 such that the i-th precursor solution layer 736-i (where i is a number and 2 < i ≤ N) remains above the bottom surface of the resin bath 728. In this regard, the successive raising of the base 716 and thus the top surface 716A of the base 716 is followed by exposure to UV light 752 having a pattern corresponding to the i-th layer layout 742-i, such that each successive cured layer of the lens is cured to form the shape of the resultant lens 714.

[0098] According to other embodiments, manufacturing the lens 714 using the additive DLP method may consist of successive curing of the precursor solution 720 beneath the top surface 716A of the base 716 as the platform 748 successively raises the base 716 within the resin bath 728 along the Z-axis and in a direction away from the bottom surface of the resin bath 728. In this manner, the UV light 752 is successively adjusted to a pattern corresponding to the layer layout 742 along the Z-axis.

[0099] Figure 8 illustrates an exemplary process flow diagram 8**00** showing the general manufacturing steps of the additive DLP method described in Figures 7A to 7C . In Figure 8 , step 801 is subdivided into sub-steps 801A to 801D, generally corresponding to Figure 7A . Sub-step 801A corresponds to providing the precursor solution 720 to the resin bath 728. Sub-step 801B corresponds to holding and moving the base 716 within the resin bath 748 along the Z-axis using the platform 748, where the top surface 716A of the base 716 faces the bottom surface of the resin bath 728. Sub-step 801C corresponds to lowering the base 716 within the resin bath 728 such that the first precursor solution layer 736-1 having a predetermined thickness T PS1 is held between the top surface 716A of the base 716 and the bottom surface of the resin bath 18. Sub-step 801D corresponds to irradiating the first precursor solution layer 736-1 with UV light 752 having a pattern corresponding to the first layer layout 742-1 through the bottom surface of the resin bath 728 using the UV projector ********, such that the first cured layer of the lens 738-1 is cured and formed above the top surface 716A of the base 716.

[0100] Step 802, which is subdivided into sub-steps 802A to 802B, generally corresponds to Figure 7BSub-step 802A corresponds to raising the abutment 716 within the resin tank 728 using platform 748, such that the second precursor solution layer 736-2 is held between the top surface of the first cured layer of lens 738-1 and the bottom surface of the resin tank 728. Sub-step 802B corresponds to irradiating the second precursor solution layer 736-2 with UV light 752 having a pattern corresponding to the second layer layout 742-2 through the bottom surface of the resin 728 using a UV projector 750, such that the second cured layer of lens 738-2 is cured and formed above and around the first cured layer of lens 738-1.

[0101] Steps 803 and 804 correspond to Figure 7C Step 803 corresponds to repeating step 802 a selected number N times to manufacture a lens 714 encapsulating the corresponding LED chip 712, thereby forming an LED package 714 as part of the LED panel 700. Step 804 describes removing any remaining precursor solution 720 from the resin tank 728, removing the LED panel 700 from the resin tank 728, and performing any optional post-processing of the LED panel 700, such as... Figure 7C As shown.

[0102] Figures 9A to 9C An additive liquid crystal display (LCD) printing method for manufacturing a lens 914 and a corresponding LED package 910 for an LED panel 900 is described. The additive LCD printing method is similar to that in previous references. Figures 7A to 7C and Figure 8 The DLP methods discussed are essentially similar, except that instead of using a UV projector 750, a UV light source or array 922 is combined with a liquid crystal to form LCD-based illumination. In this way, the patterned screen 930 is positioned to act as a mask, thereby exposing only the pixels associated with the raster pattern required to cure and form the corresponding LCD cured layer 938.

[0103] Figure 9AA substrate 916 with an LED chip 912, positioned to form a lens using an LCD printing method, is shown according to an aspect of this disclosure. As shown, a UV light array 922 is combined with a patterned screen 930 to create a UV light pattern 954, utilized in a continuous, sequential, and additive manner. The bottom surface of a resin tank 928 is transparent, allowing the UV light pattern 954 to be exposed and cured within the resin tank 928 and below the top surface 916A of the substrate 916, forming a first precursor solution layer 936-1 of the precursor solution 920. The substrate 916 is moved along the Z-axis via a platform 948, causing the precursor solution 920 to be cured continuously using the UV light pattern 954 to form a first LCD cured layer 938-1. In this manner, a continuous and integral lens 914 is formed on a predetermined area of ​​the top surface 916A of the substrate 916. The UV light pattern 954 is defined by the first patterned screen 930-1. For illustrative purposes, the removal of the substrate 916 from the resin tank 928 is shown to reveal the first LCD curing layer 938-1. In practice, the substrate 916 may or may not be removed from the resin tank 928 before an additional LCD curing layer is formed.

[0104] Figure 9B The image shows the base 916 after the formation of the second LCD curing layer 938-2, as part of a subsequent manufacturing step in the additive LCD printing method. In this regard, Figure 9B Corresponding to the use of stage 948 to raise the base stage 916 within the resin tank 928, the second precursor solution layer 936-2 is retained, and the second LCD curing layer 938-2 is formed using UV light pattern 954 through the second patterned screen 930-2. Figure 9A Similarly, in Figure 9B The image shows the base 916 being removed from the resin tank 928 to reveal the second LCD curing layer 938-2. In practice, the base 916 may or may not be removed from the resin tank 928 before the formation of the additional LCD curing layer.

[0105] Figure 9C It shows that Figure 9B The manufacturing process is repeated N times to complete the manufacturing of lens 914. Figure 9CIn this case, for illustrative purposes, the base 916 is initially shown as being removed from the resin bath 928. As described above, according to an embodiment, the base 916 may or may not remain in the resin bath 928 throughout the formation of the lens 914. The base 916 is raised within the resin bath 928 by the platform 948 such that the i-th precursor solution layer 936-i (where i is a number and 2 < i ≤ N) is maintained above the bottom surface of the resin bath 928. In this regard, the successive raising of the base 916 and thus the top surface 916A of the base 916 is followed by exposing the UV light pattern 924 through the patterned screen 930-i such that each subsequent LCD cured layer 938-i completes the formation of the shape of the resulting lens 914. Figure 9C The LED panel 900 with the plurality of LED packages 910 is further shown after removing any remaining precursor solution 920 from the resin bath 928 and removing the LED panel 900 from the resin bath 928. Any optional post-processing of the LED panel 900 may also be performed.

[0106] Figure 10 Illustrated is a description Figures 9A to 9C of an exemplary process flow diagram 1000 of the general manufacturing steps of the LCD printing method. In Figure 10 this case, step 1001 is subdivided into sub-steps 1001A to 1001D, which generally correspond to Figure 9A . Sub-step 1001A corresponds to placing the precursor solution 920 into the resin bath 928 having a transparent bottom surface. Sub-step 1001B corresponds to holding and moving the base 916 within the resin bath 928 along the Z-axis by the platform 948, where the top surface 916A of the base 916 faces the bottom surface of the resin bath 928. Sub-step 1001C corresponds to lowering the base 916 within the resin bath 928 such that the first precursor solution layer 936-1 having a predetermined thickness is maintained between the top surface 916A of the base 916 and the bottom surface of the resin bath 928. Sub-step 1001D corresponds to irradiating the first precursor solution layer 936-1 with UV light 924 having a pattern (e.g., 954) corresponding to the first patterned screen 930-1 through the bottom surface of the resin bath 928 using the UV source 922 such that the first LCD cured layer 938-1 is cured and formed above the top surface 916A of the base 916. Step 1002 is subdivided into sub-steps 1002A and 1002B, which generally correspond to Figure 9BSub-step 1002A corresponds to raising the platform 916 within the resin tank 928 using the platform 948, such that the second precursor solution layer 936-2 is held between the top surface of the first LCD curing layer 938-1 and the bottom surface of the resin tank 928. Sub-step 1002B corresponds to irradiating the second precursor solution layer 936-2 with UV light 924 having a pattern (e.g., 954) corresponding to the second patterned screen 930-2 through the bottom surface of the resin tank 928 using a UV source 922, such that the second LCD curing layer 938-2 is cured and formed above and around the first LCD curing layer 938-1. Step 1003 is used to repeat step 1002 a selected number of times N, and step 1004 is used to remove the LED panel 900 from the resin tank 928 and any post-processing, generally corresponding to Figure 9C .

[0107] Figures 11A to 11C A layer-by-layer stereolithography (SLA) printing method is described for manufacturing a lens 1114 for an LED panel 1100 and a corresponding LED package 1110. As will be discussed in more detail herein, the layer-by-layer SLA printing method involves grating a focused UV beam 1134 onto the bottom surface of a resin bath 1128 in a continuous, sequential, and layer-by-layer manner. The grating scanning of the focused UV beam 1134 is performed according to a corresponding grating pattern 1130. The bottom surface of the resin bath 1128 is transparent, allowing the focused UV beam 1134 to expose the precursor solution 1120 within the resin bath 1128 and below the top surface 1116A of the abutment 1116. The abutment 1116 is held within the resin bath 1128 using a platform 1148, which is mechanically coupled to the abutment 1116 in a position opposite to the top surface 1116A. In this manner, as the platform 1148 moves the base 1116 along the Z-axis, the top surface 1116A faces and remains parallel to the bottom surface of the resin tank 1128. Therefore, as the base 1116 moves along the Z-axis, the precursor solution 1120 is cured layer by layer to form a continuous lens 1114 on a predetermined area of ​​the top surface 1116A of the base 1116. The lens 1114 then encapsulates a corresponding LED chip 1112 to form the LED package 1110 of the LED panel 1100.

[0108] Figure 11A The display stage 1116 is positioned relative to the resin tank 1128 to form a first precursor solution layer 1136-1 of the precursor solution 1120 between the top surface 1116A of the stage 1116 and the bottom surface of the resin tank 1128. The first precursor solution layer 1136-1 is cured using a focused UV beam 1134 using a layer-by-layer SLA printing method to form a first grating layer 1138-1. In this regard, Figure 11AThe base 1116 is placed above the bottom surface of the resin tank 1128, with the top surface 1116A of the base 1116 facing the bottom surface of the resin tank 1128, such that the first precursor solution layer 1136-1 of the precursor solution 1120 is held between the top surface 1116A of the base 1116 and the bottom surface of the resin tank 1128. Figure 11A It also corresponds to rasterizing the focused UV beam 1134 onto the bottom surface of the resin tank 1128 in a continuous, sequential and layer-by-layer manner to form a first raster layer 1138-1, which forms part of the lens 1114.

[0109] A base plate 1116 is positioned within a resin tank 1128, and a platform 1148 is positioned at a height above the bottom surface of the resin tank 1128. In this manner, when the platform 1148 moves the base plate 1116 along the Z-axis, the top surface 1116A of the base plate 1116 faces and remains parallel to the bottom surface of the resin tank 1128. First, the base plate 1116 is lowered within the resin tank 1128 using the platform 1148, such that the first precursor solution layer 1136-1 of the precursor solution 1120 is held between the base plate 1116 and the bottom surface of the resin tank 1128. A UV source 1132 is positioned to provide a focused UV beam 1134. The focused UV beam 1134 is used to expose a portion of the first precursor solution layer 1136-1 of the precursor solution 1120 to selectively cure portions of the precursor solution 1120 according to a first grating pattern 1130-1 to form the first grating layer 1138-1. The first grating layer 1138-1 is disposed at least partially above each LED chip 1110 and above the top surface 1116A of the substrate 1116 to form a portion of the lens 1114. For illustrative purposes, the first grating layer 1138-1 is shown being removed from the resin tank 1128. In practice, the substrate 1116 may or may not be removed from the resin tank 1128 before forming additional grating layers.

[0110] Figure 11B The substrate 1116 is shown after the formation of the second grating layer 1138-2, as part of a layer-by-layer SLA printing method. In this regard, Figure 11B The platform 1148 is used to position the base 1116 in the resin tank 1128 so that the second precursor solution layer 1136-2 of the precursor solution 1120 is held between the top surface of the first grating layer 1138-1 and the bottom surface of the resin tank 1128. Figure 11Balso corresponds to selectively forming a second grating layer 1138-2 using a focused UV beam 1134, which forms part of the lens 1114. As the base 1116 moves along the Z-axis within the resin bath 1128, a second precursor solution layer 1136-2 of the precursor solution 1120 accumulates between the base 1116 and the bottom surface of the resin bath 1128. After the stepwise elevation of the base 1116, successive layers 1136 of the precursor solution 1120 are exposed to the focused UV beam 1134 to fabricate the interleaved and integral grating layers 1138. In this regard, the focused UV beam 1134 is used to expose and cure a predetermined area according to the second grating pattern 1130-2. As in Figure 11A , in Figure 11B the base 1116 is removed from the resin bath 1128 to show the second grating layer 1138-2. In practice, the base 1116 may or may not be removed from the resin bath 1128 before forming additional grating layers.

[0111] Figure 11C shows the fabrication of the LED panel 1100 by repeating the fabrication steps as shown in Figure 11B a selected number of times N to fabricate the lens 1114 having interleaved grating layers as part of a layer-by-layer SLA printing method. In Figure 11C for illustrative purposes, the base 1116 is initially shown removed from the resin bath 1128. As described above, according to an embodiment, the base 1116 may or may not remain in the resin bath 1128 throughout the formation of the lens 1114. Figure 11C represents repeating the fabrication steps of Figure 11B a selected number of times N to fabricate the LED panel 1100. In Figure 11C the base 1116 is positioned along the Z-axis using the platform 1148 such that the i-th precursor solution layer 1136-i of the precursor solution 1120 (where i is a number and 2 < i ≤ N) is positioned between the base 1116 and the bottom surface of the resin bath 1128. After the stepwise elevation of the base 1116, each successive precursor solution layer 1136-i is raster scanned with the focused UV beam 1134 according to the corresponding grating pattern 1130-i. In this way, the grating layers 1138 can be continuously interleaved and integrated to form the lens 1114 of the LED chip 1112 encapsulating the LED package 1110. Figure 11C also shows the LED panel 1100 having multiple LED packages 1110 after removing any remaining precursor solution 1120 from the resin bath 1128 and removing the LED panel 1100 from the resin bath 1128. Any optional post-processing of the LED panel 1100 may also be performed.

[0112] Figure 12 shows the description of Figures 11A to 11CAn exemplary process flow diagram 1200 illustrates the general manufacturing steps of a layer-by-layer SLA printing method. Figure 12 In the middle, step 1201 roughly corresponds to Figure 11A The process involves providing a precursor solution 1120 to a resin tank 1128 having a transparent bottom surface; holding and moving a platform 1148 along the Z-axis within the resin tank 1128, with the top surface 1116A of the platform 1116 facing the bottom surface of the resin tank 1128; lowering the platform 1116 within the resin tank 1128 to form a first precursor solution layer 1136-1; and curing a predetermined area of ​​the first precursor solution layer 1136-1 using a focused UV beam 1134 to form a first grating layer 1138-1. Step 1202 generally corresponds to... Figure 11B This is used to raise the stage 1116 within the resin tank 1128 to form a second precursor solution layer 1136-2 and to cure a predetermined area of ​​the second precursor solution layer 1136-2 using UV light to form a second grating layer 1138-2. Step 1203 generally corresponds to... Figure 11C This is used to repeat step 1202 a selected number of times N to manufacture a lens 1114 that encapsulates the corresponding LED chip 1112, thereby forming the LED package 1110 of the LED panel 1100. Step 1204 also corresponds to... Figure 11C Used to remove the LED panel 1100 from the resin tank 1128 and any optional post-processing.

[0113] As described above, various additive and / or layer-by-layer manufacturing techniques are provided for forming LED lenses as primary optical devices in LED packages. The LED lens is integrated as part of the LED package and can also encapsulate a corresponding LED chip. In this way, the lens can be formed as continuous layers, allowing the LED chip to be effectively embedded within the lens material. This enables the following: Figures 3A to 4 Layer-by-layer additive printing method Figures 5A to 6 Injection printing method Figures 7A to 8 Layer-by-layer DLP method Figures 9A to 10 SLA printing method, and / or Figures 11A to 12 This additive manufacturing technique in LCD printing methods is used to form complex lens shapes as primary optics in LED packages. As described above, this primary optics can be formed from materials used as the primary package body for LED chips. For example, the material can cover or directly cover portions of the LED chip and the underlying substrate.

[0114] As described herein, the principles of this disclosure provide the ability to have complex optical shapes typically achieved by secondary optics in conventional applications. Complex optical shapes can include multiple cavities or voids embedded within the lens material to form integrated refractive index steps and / or interfaces. These cavities can form air cavities, or they can be filled with another material, such as a gas, liquid, gel, or a solid material that is typically different from the lens material. For air cavity implementations, additive manufacturing techniques are used to sequentially form the cavities according to the desired shape. For implementations where the cavities are filled with another material, additive manufacturing can be paused while the cavity is still open from the top surface, and the filling material can be dispensed or otherwise provided within the cavity. After the filling material is provided, additive manufacturing can be resumed to close the cavity.

[0115] As described above, lenses with complex optical shapes can be directly formed on the substrate and / or LED panel using advanced manufacturing techniques. Therefore, such lenses with complex optical shapes can be integrated within the LED package without the need for adhesive materials associated with bonding the pre-formed lens structure to the LED package. Figures 13 to 22 This refers to an exemplary LED package having a lens with a cavity and / or other complex shape, which can be achieved through the above-described... Figures 3A to 12 Any additive manufacturing technology described herein.

[0116] Figure 13This is a perspective view of an LED package body 1310 having a lens 1314 according to the principles of this disclosure, the lens having a cavity 1354 formed within the material of the lens 1314. The LED package 1310 includes a base 1316 and an LED chip 1312 mounted thereon. As shown, the lens may have a base 1314A with a width or diameter increasing with distance from the base 1316 and a generally curved top 1314B. In this way, the outer wall 1314W of the base 1314A may be angled outward from the base 1316 to direct light toward the top 1314B. By forming the lens 1314 according to the additive manufacturing principle described above, the base 1314A and the top 1314B are continuous with each other and there is no seam associated with two separately formed elements joined together. The cavity 1354 can be positioned within the continuous material of the lens 1314 such that the cavity 1354 is completely embedded within the lens 1314. As used herein, the continuous material of lens 1314 means that the material is continuous and has no seams associated with joining or otherwise connecting the two lens portions together. Cavity 1354 may form an air cavity or may retain a filling material as described above. In this way, cavity 1354 can provide an index of refraction step within lens 1314, which is configured to guide light in a desired direction within lens 1314 by refraction and / or reflection. Because cavity 1354 is formed according to the additive manufacturing principle described above, precise control over the position and size of cavity 1354 can be achieved. In some embodiments, cavity 1354 may be suspended within the material of lens 1314, spaced above LED chip 1312. Figure 13 In this embodiment, cavity 1354 is suspended within base 1314A near LED chip 1312 for receiving light. In some embodiments, cavity 1354 is formed into an ellipsoidal shape, with its longest dimension ranging from 25 micrometers (µm) to 4000 µm. As used herein, ellipsoidal shape includes spherical and non-spherical shapes.

[0117] Figure 14 Is with Figure 13 A perspective view of an LED package 1410 similar to the LED package 1310, except that the cavity 1456 in the lens 1414 of the LED package 1410 is formed with a semi-ellipsoidal shape. The LED package 1410 includes a base 1416 and an LED chip 1412 mounted thereon. As shown, the lens 1414 may have a base 1414A and a top 1414B, the width or diameter of the base 1414A increasing with distance from the base 1416, and the top 1414B increasing with distance from the base 1416. Figure 13A similar, roughly curved shape. The cavity 1456 is formed into a semi-ellipsoidal shape with a roughly planar surface that most closely approximates the LED chip 1412. Figure 13 Similarly, cavity 1456 can be fully embedded in the continuous material of lens 1414 and positioned within base 1414A, and cavity 1456 can form an air pocket or filling material can reside within cavity 1456.

[0118] Figure 15 Is with Figure 13 A perspective view of an LED package 1510 similar to the LED package 1310, except that the cavity 1558 of the LED package 1510 is formed close to the base 1516. In this manner, the cavity 1558 is formed around the LED chip 1512, such that the material of the lens 1514 is spaced apart from the LED chip 1512. Therefore, the LED chip 1512 is effectively encapsulated by the cavity 1558, which in turn is encapsulated by the lens 1514. As shown, the lens 1514 may have a base 1514A and a top 1514B, the width or diameter of which increases with distance from the base 1516, and the top 1514B being aligned with... Figure 13 A similar, generally curved, manner is employed. Cavity 1558 is formed into a semi-ellipsoidal shape, having a generally flat surface on the abutment 1516, such that the curved upper surface of the semi-ellipsoidal shape is bent to guide light into lens 1514. Cavity 1558 may form an air cavity or a filling material may reside within cavity 1558.

[0119] Figure 16 Is with Figure 13 A 3D view of LED package 1610, similar to LED package 1310, with the difference being... Figure 16 The top surface 1614T of lens 1614 forms a Fresenel lens. According to the additive manufacturing principle of this disclosure, complex shapes (e.g., a Fresenel lens for the top surface 1614T) can be integrated within a continuous material of lens 1614. As shown, lens 1614 may have a base 1614A, the width or diameter of which is consistent with... Figure 13 Similar arrangements increase with distance from the base 1616, as does the top 1614B having the aforementioned top surface 1614T. In some embodiments, the top surface 1614T with a Fresnel lens can be used in combination with any cavity described herein.

[0120] Figure 17 Is with Figure 15A perspective view of an LED package 1710 similar to the LED package 1510, except that a cuboid-shaped cavity 1760 is formed near the base 1716. This cuboid shape provides light entering the lens 1714 from the LED chip 1712 with... Figure 15 The cavity 1558 has a semi-ellipsoidal shape with different light patterns. Additive manufacturing techniques, as described herein, provide the ability to easily provide various shapes of the cavity 1760. As shown, the lens 1714 may have a base 1714A, the width or diameter of which is... Figure 13 Similar patterns increase with distance from the base 1716, as well as the top 1714B located above the base 1714A.

[0121] Figure 18 This is in relation to the embodiment of lens 1814, which has a generally curved shape. Figure 13 A perspective view of an LED package 1810 similar to the LED package 1310. As shown, a lens 1814 is formed into a semi-ellipsoidal or hemispherical shape on the surface of the base 1816 of the LED package 1810. A cavity 1862 forming an ellipsoidal shape is provided to correspond with the above-described... Figure 13 The LED package 1310 is disposed within a continuous material of the lens 1814 in the manner described.

[0122] Figure 19 This is for the implementation of the 1964 with multiple cavities. Figure 18 A perspective view of an LED package 1910 similar to the LED package 1810. As shown, the LED chip 1912 is on the base 1916 of the LED package 1910, and multiple cavities 1964 are formed within the material of the lens 1914. Figure 19 In this configuration, cavity 1964 is positioned near the peripheral side of lens 1914. In this manner, the provided refractive index step can effectively guide and / or concentrate wide-angle light from LED chip 1912 in a direction perpendicular to the surface of substrate 1916. Therefore, cavity 1964 can be positioned to redirect lateral light to provide an emission pattern with a narrower beam.

[0123] Figure 20 This is related to an embodiment in which multiple cavities 2066 form a periodic array within a lens 2014. Figure 19 A perspective view of an LED package 2010 similar to the LED package 1910. As shown, an LED chip 2012 is located on a base 2016 of the LED package 2010, and an array of cavities 2066 is formed within a continuous material of a lens 2014. The additive manufacturing technique described herein allows for precise control over the position of each cavity 2066. Figure 20In the process, the cavities 2066 are formed in rows with a common spacing, and the number of cavities 2066 in the row gradually decreases with the distance away from the base 2016.

[0124] Figure 21 This is in relation to an embodiment including multiple cavities 2168 having an ellipsoidal shape. Figure 19 A perspective view of an LED package 2110 similar to the LED package 1910. As shown, an LED chip 2112 is located on a base 2116 of the LED package 2110, and a plurality of cavities 2168 are formed within a continuous material of a lens 2014. The plurality of cavities 2168, having an ellipsoidal shape, can be positioned adjacent to each other and above the LED chip 2112, and the portion of the lens 2114 between the cavities 2168 can be centrally positioned above the LED chip 2112 to provide a desired light emission pattern.

[0125] Figure 22 This refers to an embodiment where the cavity 2270 forms a non-circular geometry. Figure 13 A perspective view of an LED package 2210 similar to the LED package 1310. As shown, the LED chip 2212 is on the base 2216 of the LED package 2210, and the cavity 2270 is formed within the continuous material of the lens 2214. Figure 22 In this cavity, 2270 is formed into a pyramid shape, with its bottom closest to the LED chip 2212. In this way, light from the LED chip 2212 can interact with the cavity 2270 and be redirected in the desired emission pattern.

[0126] Figure 23 This is in relation to the embodiment of lens 2314 with an asymmetrical shape. Figure 13 A cross-sectional view of an LED package 2310 similar to that of an LED package 1310 is shown. As illustrated, the LED chip 2312 is located on the base 2316 of the LED package 2310 in a manner similar to that of the previous embodiment. A lens 2314 can be formed according to the additive manufacturing principles described herein. Therefore, complex shapes can be used to shape light emission in a desired direction. Figure 23In the example, lens 2314 is configured to preferably guide light away from the first wall 2314-1 and toward the second wall 2314-2. The first wall 2314-1 may be formed with an angle that tapers toward the center of the LED package 2310 with distance away from the substrate 2316. In some embodiments, the first wall 2314-1 may be planar. The second wall 2314-2 may be formed with a curved surface that curves outward from the first wall 2314-1 and from the surface of the sub-substrate 2316. In this regard, the shape of lens 2314 is configured to provide an emission pattern with an off-center peak or highest emission concentration. Such an emission pattern is suitable for height-adjustable displays. An asymmetrical shape of lens 2314 is provided as an example. Using the additive manufacturing techniques described herein, the shape of the lens can be easily modified for different applications with different emission patterns. Additionally, any cavity as described above can be easily incorporated into lens 2314.

[0127] It is anticipated that any of the foregoing aspects, and / or the various individual aspects and features described herein, may be combined to obtain additional advantages. Unless otherwise indicated herein, any of the various embodiments disclosed herein may be combined with one or more other disclosed embodiments.

[0128] Those skilled in the art will recognize improvements and modifications to the preferred embodiments of this disclosure. All such improvements and modifications are considered to be within the scope of the concepts disclosed herein and the subsequent claims.

Claims

1. A light-emitting diode (LED) package, comprising: Support structure; LED chips on the support structure; as well as The lens on the support structure forms a package for the LED chip, the lens forms a cavity completely embedded in a continuous material of the lens, and the cavity forms a refractive index step with the continuous material of the lens.

2. The LED package according to claim 1, wherein, The longest dimension of the cavity ranges from 25 micrometers (µm) to 4000 µm.

3. The LED package according to claim 1, wherein, The cavity forms an ellipsoidal shape within the lens.

4. The LED package according to claim 1, wherein, The cavity forms an air cavity within the lens.

5. The LED package according to claim 1, wherein, The cavity is filled with a filling material that is different from the continuous material of the lens.

6. The LED package according to claim 1, wherein, The lens forms a base on the support structure and a top spaced apart from the support structure by the base, the base having a width that increases with the distance from the support structure.

7. The LED package according to claim 6, wherein, The top surface of the lens at the top is formed as a Fresnel lens.

8. The LED package according to claim 1, wherein, The cavity is a first cavity, and the lens also forms a second cavity embedded within the continuous material of the lens.

9. The LED package according to claim 1, wherein, The cavity is one of a cavity array, which forms a periodic array within the continuous material of the lens.

10. The LED package according to claim 1, wherein, The lens forms an asymmetrical shape relative to the base.

11. A light-emitting diode (LED) package, comprising: Support structure; LED chips on the support structure; as well as A lens is formed directly on the support structure, the lens forming a cavity on the support structure, the cavity separating the LED chip from the lens material.

12. The LED package according to claim 11, wherein, The cavity surrounds the LED chip in a semi-ellipsoidal shape.

13. The LED package according to claim 11, wherein, The cavity is shaped like a cuboid.

14. The LED package according to claim 11, wherein, The cavity forms an air cavity around the LED chip.

15. The LED package according to claim 11, wherein, The cavity is filled with a filling material that is different from the material of the lens.

16. A method for manufacturing a light-emitting diode (LED) package, the method comprising: Provides a base with LED chips installed; as well as Lenses are formed on the substrate and the LED chip by additive molding, the additive molding comprising progressively curing the precursor material of the lens in a direction away from the substrate.

17. The method according to claim 16, wherein, The progressive curing of the precursor material includes progressively curing a progressive layer of the precursor material in a direction away from the substrate.

18. The method according to claim 16, wherein, The progressive curing of the precursor material includes continuously curing the precursor material in the direction away from the substrate.

19. The method of claim 16, further comprising forming a cavity in the lens, the cavity comprising air or a filling material, the filling material being a material different from the lens.

20. The method of claim 16, wherein, The base and the LED chip are part of an LED panel, and multiple lenses are formed by progressively curing the precursor material of the lens in a direction away from the base.

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