LED device and light emitting apparatus

Abstract

This invention provides an LED device and a light-emitting apparatus. The LED device includes a substrate, a light-window lens, and a chip. The light-window lens includes a base layer and several patterned structures, which are periodically arranged above the base layer. On one hand, the patterned structures are conical, reducing total internal reflection and increasing light extraction efficiency. On the other hand, the patterned structures include a first portion and a second portion formed above the first portion, with the refractive index of the second portion being less than that of the first portion. This allows light to gradually transition from the first portion with a higher refractive index to the second portion with a lower refractive index during emission, ultimately reaching the air. This further reduces total internal reflection and increases light transmission, thereby significantly improving the light extraction efficiency.

Description

Technical Field

[0001] This invention relates to the field of LED packaging technology, specifically to an LED device and a light-emitting device. Background Technology

[0002] Traditional LED optoelectronic component packaging uses glass optical windows (referred to as optical windows) to ensure airtightness, effectively protecting core components such as chips, while maintaining sufficiently low cost and ease of processing, which is conducive to widespread application in the civilian market. For high-brightness lighting LED devices, such as lighthouses and off-road vehicle searchlights, the optical window, in addition to meeting airtightness and protection functions, needs extremely high light extraction efficiency. However, due to the presence of the fluorescent ceramic sheet and the optical window, light needs to pass through an optically denser medium to transmit into an optically less dense medium (i.e., air). Wide-angle light is prone to total internal reflection on the planar optical window, resulting in low light extraction efficiency. Summary of the Invention

[0003] In view of the shortcomings of the prior art described above, the present invention provides an LED device and a light-emitting device. The LED device includes a substrate, a light-window lens, and a chip. The light-window lens includes a base layer and several patterned structures, which are periodically arranged above the base layer. On the one hand, the patterned structures are closely arranged conical structures, which reduces the probability of total internal reflection and improves the light transmittance. On the other hand, the patterned structures include a first part and a second part formed above the first part, and the refractive index of the second part is less than that of the first part. This allows the light to gradually transition from the first part with a higher refractive index to the second part with a lower refractive index during emission, finally reaching the air. Compared to light traveling directly from a denser medium to the air, this structure is beneficial for further reducing total internal reflection, thereby greatly improving the light transmittance.

[0004] To achieve the above and other related objectives, the present invention provides an LED device, comprising:

[0005] A substrate, wherein a metallized circuit layer is provided on the front side of the substrate;

[0006] A light window cover is disposed above the front side of the substrate, forming a cavity with the substrate. The light window cover includes a metal component and a light window lens. The metal component forms the sidewall of the cavity and is connected to the metallized circuit layer. The metal component forms a light-transmitting hole in the middle region of the cavity. The light window lens covers the light-transmitting hole and is sealed to the metal component. The light window lens includes a base layer and several patterned structures. The several patterned structures are periodically arranged above the base layer, and the patterned structures are conical structures.

[0007] The chip is fixed on the substrate and located within the cavity.

[0008] The present invention also provides a light-emitting device, including a circuit board and a plurality of light-emitting devices, wherein the light-emitting devices include the aforementioned LED devices.

[0009] The LED device and light-emitting apparatus provided by this invention have at least the following beneficial effects:

[0010] The LED device provided by this invention includes a substrate, a light-window lens, and a chip. The light-window lens comprises a base layer and several patterned structures, which are periodically and closely arranged above the base layer. On one hand, the patterned structures are closely arranged conical structures, reducing total internal reflection and increasing light extraction efficiency. On the other hand, the patterned structures include a first portion and a second portion formed above the first portion, with the refractive index of the second portion being less than that of the first portion. This allows light to gradually transition from the first portion with a higher refractive index to the second portion with a lower refractive index during emission, finally reaching the air, further reducing total internal reflection and thus greatly improving light transmittance.

[0011] The light-emitting device provided by the present invention is based on the above-mentioned LED device, and therefore has the same technical effect. Attached Figure Description

[0012] Figure 1 The diagram shown is a structural schematic of the LED device provided in Embodiment 1.

[0013] Figure 2 The image shown is a top view of the LED device provided in Embodiment 1.

[0014] Figure 3 This shows a schematic diagram of the optical window lens in Embodiment 1.

[0015] Figure 4 The diagram shown is a structural schematic of the light-emitting device provided in Embodiment 2.

[0016] Component designation explanation

[0017] 10 substrate

[0018] 11 Metallized circuit layer

[0019] 100 cavities

[0020] 20 Light Window Cover Plate

[0021] 21 Metal parts

[0022] 22-Glass Window Lens

[0023] 221 Basal layer

[0024] 222 Graphical Structure

[0025] 2221 Graphical Structure Part 1

[0026] 2222 Graphical Structure Part Two

[0027] 30 chips

[0028] 40 Fluorescent Ceramic Plate

[0029] 50 Solder

[0030] 61 Die-bonding framework

[0031] 62 Lead Frame

[0032] 70 lead wire

[0033] 80 Line Layer

[0034] 90 conductive hole

[0035] 1000 circuit board

[0036] 2000 Light-emitting devices Detailed Implementation

[0037] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0038] It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Although the illustrations only show components related to the present invention and are not drawn according to the actual number, shape and size of the components, the shape, quantity, positional relationship and proportion of each component can be arbitrarily changed under the premise of realizing the technical solution of this invention, and the layout of the components may also be more complex.

[0039] Example 1

[0040] This embodiment provides an LED device, such as... Figure 1 As shown, it includes a substrate 10, a light window cover plate 20, and a chip 30.

[0041] As an example, substrate 10 is a heat dissipation substrate. In one optional embodiment, substrate 10 is a ceramic substrate; in another optional embodiment, substrate 10 can also be a metal substrate, such as aluminum, copper, etc.; in other optional embodiments, substrate 10 can also be made of other composite materials with high thermal conductivity and reflective properties, such as aluminum silicon carbide substrates, graphene-coated metal substrates, etc. Furthermore, aluminum can be plated on the surface of substrate 10 or a high-reflectivity coating material, such as polytetrafluoroethylene, can be used to further improve the overall light output performance of the device in the invisible light band, especially the UVC band.

[0042] Combination Figure 1 and Figure 2 As shown, a metallized circuit layer 11 is provided around the substrate 10 for sealing the substrate 10 and the light window cover plate 20 together by resistance welding or fusion welding. As an example, the thickness of the metallized circuit layer 11 is greater than or equal to 60 μm, and the surface of the metallized circuit layer 11 is plated with gold or nickel-gold.

[0043] like Figure 1 As shown, the light window cover plate 20 is disposed above the substrate 10, and the size of the light window cover plate 20 matches the size of the substrate 10. In this embodiment, the substrate 10 has a planar structure, and the light window cover plate 20 has a cavity structure; therefore, a cavity 100 is formed between the substrate 10 and the light window cover plate 20. In other alternative embodiments, the substrate 10 may also have a cavity structure, and the corresponding light window cover plate 20 may have a planar structure, with a cavity 100 also formed between the substrate 10 and the light window cover plate 20. As an example, the depth of the cavity 100 is at least 0.5 mm.

[0044] like Figure 1 As shown, the light window cover plate 20 includes a metal part 21 and a light window lens 22. The metal part 21 has a light-transmitting hole, and the light window lens 22 covers the light-transmitting hole.

[0045] As an example, a metal component 21 is disposed on the heat dissipation area 11 to form the sidewall of the cavity 100. The bottom edge of the metal component 21 has an extended metal weld edge for welding connection with the heat dissipation area 11, and the width of the metal weld edge is at least 0.3 mm. In this embodiment, the metal component 21 is made of Kova alloy, copper, or aluminum, and the surface of the metal component 21 needs to be nickel plated.

[0046] like Figure 3 As shown, the optical window lens 22 includes a base layer 221 and several patterned structures 222. These patterned structures 222 are periodically and closely arranged above the base layer 221, with minimal gaps between adjacent patterns. That is, the planar area between the patterned structures 222 should be as small as possible, preferably zero, meaning adjacent patterns are closely connected. Since total internal reflection easily occurs in a plane, therefore… Figure 3The close-packed pattern structure 222 shown minimizes the probability of total internal reflection, greatly improves light transmittance, and enhances luminous efficiency.

[0047] As an example, the substrate 221 is made of a material with a light transmittance of 80% or higher, such as sapphire. In this embodiment, the refractive index of the substrate 221 is between 1.3 and 4, and the difference between the refractive index of the substrate 221 and the refractive index of the fluorescent ceramic plate 40 disposed below the substrate 221 is less than or equal to 0.05. That is, the refractive index of the substrate 221 is similar to that of the fluorescent ceramic plate 40, thereby reducing the probability of total internal reflection during the process of light emanating from the fluorescent ceramic plate 40 to the substrate 221 and improving the light extraction efficiency.

[0048] like Figure 3 As shown, the pattern structure 222 includes a first portion 2221 and a second portion 2222 formed above the first portion. As an example, the first portion 2221 is formed from a portion of the substrate layer 221; therefore, the material forming the first portion 2221 is the same as the material forming the substrate layer 221, i.e., the refractive index of the first portion 2221 is also between 1.3 and 4. As an example, the material forming the second portion 2222 is different from the material forming the substrate layer 221, and the second portion 2222 is made of a material with a transmittance greater than or equal to 80%, such as silicon dioxide. In this embodiment, the refractive index of the second portion 2222 is between 1.2 and 3, which is less than the refractive index of the first portion 2221. Using such a composite material structure allows light to gradually transition from the substrate layer 221 and the first portion 2221, which have a higher refractive index, to the second portion 2222, which has a lower refractive index, during emission, and finally reach the air. Compared to light entering the air directly from an optically denser medium, this structure helps to reduce the probability of total internal reflection and increase the transmittance of light.

[0049] As an example, graphic structure 222 is a conical structure, such as a circular cone or a polygonal cone. The polygonal cone can be a triangular pyramid, a square pyramid, a pentagonal pyramid, or a hexagonal pyramid. Designing graphic structure 222 as a cone helps improve the light extraction rate. Figure 3 As shown, the width of the graphic structure 222 is d and the height is h, and 0.1μm≤d≤100μm, 0.1d≤h≤5d. Setting the ratio of the width d to the height h of the graphic structure 222 within an appropriate range will prevent the cone from being too sharp, which would cause problems with the uniformity of the graphic; it will also prevent the cone from being too flat, which would fail to increase the light transmission effect.

[0050] As an example, the first part 2221 is a conical frustum structure, and the second part 2222 is a structure with a cross-sectional area that gradually decreases from bottom to top. The cross-sectional area at the top of the first part 2221 is equal to the cross-sectional area at the bottom of the second part 2222. For example, the first part 2221 can be a frustum or a pyramidal structure, and the second part 2222 can be a cone or a pyramidal structure. In this embodiment, the height of the first part 2221 accounts for 5% to 95% of the total height h of the graphic structure 222. A height below 5% or above 95% will result in an uneven transition of light from the high-refractive-index region to the low-refractive-index region, affecting the final transmittance of the light.

[0051] like Figure 1 As shown, a fluorescent ceramic plate 40 is disposed on the side of the optical window lens 22 facing the cavity 100. The fluorescent ceramic plate 40 is located inside the cavity 100 and is used to convert the light emitted by the chip 30 into white light. As an example, the fluorescent ceramic plate 40 is mainly composed of phosphor and substrate material. The phosphor is usually composed of rare earth elements, metal oxides, etc., and has good fluorescence performance, which can convert the absorbed photon energy into fluorescence. The substrate material is usually a transparent ceramic material, such as alumina, silicon dioxide, etc., which has high heat resistance, chemical corrosion resistance and mechanical strength. In this embodiment, replacing the traditional phosphor coating with the fluorescent ceramic plate 40 can enable the LED device to have higher fluorescence efficiency and longer service life.

[0052] like Figure 1 As shown, a solder 50 is provided between the optical window lens 22 and the metal part 21 for sintering and connecting the optical window lens 22 and the metal part 21. As an example, the solder 50 is annular; the solder 50 is made of inorganic material with the composition TiCuBiZnMn, wherein Ti accounts for 6.8%–25%, Cu accounts for 19.6%–34%, Bi accounts for 4.2%–7.3%, Zn accounts for 21%–37%, and Mn accounts for 0.56%–1.2%. In other alternative embodiments, the optical window lens 22 and the metal part 21 can also be connected by fusion welding, in which case the solder 50 is not required.

[0053] like Figure 1As shown, chip 30 is located within cavity 100 and fixed to die bond frame 61 by conductive adhesive. As an example, the number of chips 30 can be one or more; this embodiment uses one as an example. In an optional embodiment, chip 30 is a green or blue light chip, which is a top-surface terminal type chip. On the surface opposite to die bond frame 61, chip 30 has two terminals (not shown in the figure), each connected to a different lead frame 62 via different leads 70. In other optional embodiments, chip 30 is a red light chip, which is a vertically conductive type chip. On the surface near die bond frame 61, chip 30 has one terminal (not shown in the figure) soldered to die bond frame 61. On the surface opposite to die bond frame 61, chip 30 has another terminal (not shown in the figure), connected to lead frame 62 via a lead 70. As an example, die bond frame 61 and lead frame 62 are made of the same conductive material.

[0054] As an example, lead 70 is used to connect chip 30 to lead frame 62. In this embodiment, lead 70 is a metal wire, for example, made of one of the materials Al, Cu, Ag, and Au. Metal wires, as leads, have good conductivity, mechanical strength, thermal stability, and cost-effectiveness, making them suitable for various electronic applications and manufacturing needs.

[0055] As an example, cavity 100 is filled with an encapsulating colloid (not shown in the figure). In this embodiment, the encapsulating colloid is a transparent resin, such as silicone or epoxy resin, which has high resistance to light and heat, thereby extending the lifespan of the device.

[0056] like Figure 1 As shown, a circuit layer 80 is provided on the back side of the substrate 10, and a conductive hole 90 is provided in the substrate 10 through its front and back sides. The die bond frame 61 and the lead frame 62 are respectively connected to the circuit layer 80 through the conductive hole 90, thereby realizing the connection between the chip 30 and the circuit layer 80.

[0057] The LED device provided in this embodiment includes a substrate 10, a light-window lens 20, and a chip 30. The light-window lens 20 includes a base layer 221 and several patterned structures 222, which are periodically arranged above the base layer 221. On one hand, the patterned structures 222 are conical, which reduces total internal reflection and improves light extraction efficiency. On the other hand, the patterned structures 222 include a first portion 2221 and a second portion 2222 formed above the first portion. The refractive index of the second portion 2222 is less than that of the first portion 2221, so that during the light emission process, the light gradually transitions from the first portion with a larger refractive index to the second portion with a smaller refractive index, and finally reaches the air, further reducing total internal reflection and thus greatly improving light transmittance.

[0058] Example 2

[0059] This embodiment provides a light-emitting device, such as... Figure 4 As shown, the device includes a circuit board 1000 and at least one light-emitting device 2000. The light-emitting device 2000 is disposed on the surface of the circuit board 1000. A conductive adhesive film (not shown in the figure) is disposed on the surface of the circuit board 1000. The circuit board 1000 is electrically connected to the electrodes of the light-emitting device 2000 through the conductive adhesive film. In this embodiment, the light-emitting device 2000 is the LED device provided in Embodiment 1, and its specific structure is described in Embodiment 1, and will not be repeated here.

[0060] The light-emitting device provided in this embodiment is based on the LED device provided in Embodiment 1. Therefore, the light-emitting device provided in this embodiment also has a high light extraction rate and high brightness. In addition, it can effectively utilize light energy and minimize energy loss.

[0061] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. An LED device, characterized in that, include: A substrate, wherein a metallized circuit layer is provided on the front side of the substrate; A light window cover is disposed above the front side of the substrate, forming a cavity with the substrate. The light window cover includes a metal component and a light window lens. The metal component forms the sidewall of the cavity and is connected to the metallized circuit layer. The metal component forms a light-transmitting hole in the middle region of the cavity. The light window lens covers the light-transmitting hole and is sealed to the metal component. The light window lens includes a base layer and several patterned structures. The several patterned structures are periodically arranged above the base layer. The patterned structures are conical structures. The patterned structures include a first part and a second part formed above the first part. The first part is a conical mesa structure. The second part is a structure with a cross-sectional area that gradually decreases from bottom to top. The material forming the first part is the same as the material of the base layer, and the material forming the second part is different from the material of the base layer. The refractive index of the first part is greater than that of the second part. A fluorescent ceramic plate is located inside the cavity and fixed to the side of the optical window lens facing the cavity, and the difference between the refractive index of the first part and the refractive index of the fluorescent ceramic plate is less than or equal to 0.

05. The chip is fixed on the substrate and located within the cavity.

2. The LED device of claim 1, wherein, The graphic structure is a conical structure or a polygonal conical structure.

3. The LED device of claim 1, wherein, The width of the bottom of the graphic structure is d, and the height of the graphic structure is h, where 0.1d ≤ h ≤ 5d.

4. The LED device according to claim 2, characterized in that, Furthermore, the projected area of ​​the first part on the plane where the base layer is located is greater than or equal to the projected area of ​​the second part on the plane where the base layer is located.

5. The LED device according to claim 1, characterized in that, The height of the first part accounts for 5% to 95% of the height of the graphic structure.

6. The LED device of claim 1, wherein, The refractive index of the first part ranges from 1.3 to 4, and the refractive index of the second part ranges from 1.2 to 3.

7. The LED device of claim 1, wherein, A ring-shaped solder is provided between the optical window lens and the metal part.

8. A light emitting device comprising: It includes a circuit board and multiple light-emitting devices, wherein the light-emitting devices include the LED device according to any one of claims 1 to 7.

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