Light emitting unit, light source machine, and near-eye display

Abstract

The application provides a light-emitting unit, comprising: at least two light-emitting panels configured to emit light; and a substrate, on which windows are formed, each window being aligned with at least one light-emitting panel. The application also provides a light source machine and a near-eye display. By the application, monochromatic light-emitting panels can be used to provide mixed-color light sources, such as white light sources, while the size of the light source machine or the display can be reduced.

Description

Technical Field

[0001] This invention relates to the field of micro light-emitting diodes, and in particular to a light-emitting unit, a light source, and a near-eye display. Background Technology

[0002] A micro light-emitting diode (LED) is a novel LED structure created by thinning, miniaturizing, and arraying existing LED structures. It integrates arrayed micron-sized LED units onto an active-addressable driver panel to enable individual LED illumination and control, thereby outputting the desired display image. The core structure of a micro LED is a PN junction diode, constructed from a direct bandgap semiconductor material. When a forward bias voltage is applied to the upper and lower electrodes, allowing current to flow, electrons and holes recombine in the active region, simultaneously emitting a single-color photon.

[0003] Currently, to provide white light or light sources other than the three primary colors, white light-emitting diodes (LEDs) or miniature LEDs capable of providing that color are typically used to form light-emitting panels or light sources. However, mixed-color miniature LEDs are expensive, and the resulting light source is a fixed color with poor color-tuning capabilities. Furthermore, such light sources also suffer from large size issues. Summary of the Invention

[0004] Based on existing technology, the objective of this invention is to provide a light-emitting unit, a light source, and a near-eye display, which can use a monochromatic light-emitting panel to provide a mixed-color light source, such as a white light source, while also reducing the size of the light source or the display.

[0005] In a first aspect of the present invention, the aforementioned task is accomplished by a light-emitting unit comprising:

[0006] At least two light-emitting panels are configured to emit light; and

[0007] A substrate having windows, each window being aligned with at least one light-emitting panel.

[0008] In one embodiment of the present invention, the substrate is electrically connected to the light-emitting panel via a flip-chip package.

[0009] In another embodiment of the present invention, the substrate includes:

[0010] A first contact portion is disposed on the surface of the substrate facing the light-emitting panel for electrical contact between the circuitry of the substrate and the solder balls; and

[0011] Solder ball, configured to electrically connect a first contact portion to a second contact portion disposed on the light-emitting panel, wherein the second contact portion is used for electrical connection of the light-emitting panel.

[0012] In another embodiment of the present invention, the light-emitting panel includes:

[0013] A miniature light-emitting diode array configured to emit light; and

[0014] A driving backplane that carries the micro LED array and is configured to drive the micro LED array, wherein a second contact portion is disposed on the driving backplane.

[0015] In another embodiment of the invention, a welding post is provided between the second contact portion and the welding ball for electrical connection between the welding ball and the second contact portion.

[0016] In another embodiment of the present invention, the first contact portion and / or the second contact portion includes at least one of the following:

[0017] Through-hole contact portion and contact point.

[0018] In another embodiment of the present invention, the light-emitting unit further includes a connector disposed on the substrate to connect the light-emitting panel to an external control source or an external power supply.

[0019] In another embodiment of the present invention, the driving backplane is spaced apart, and each micro light-emitting diode array is spaced apart on the corresponding driving backplane.

[0020] In another embodiment of the invention, the connector includes at least one of the following:

[0021] Gold fingers and stitches.

[0022] In another embodiment of the present invention, the light-emitting unit further includes:

[0023] A heat sink is disposed on the back side of the light-emitting panel and spaced apart from the light-emitting panel, wherein thermally conductive adhesive is disposed between the heat sink and the light-emitting panel to dissipate the heat generated by the light-emitting panel.

[0024] In another embodiment of the present invention, thermally conductive adhesive is provided between the heat sink and the substrate to dissipate the heat generated by the substrate.

[0025] In another embodiment of the invention, the material of the thermally conductive adhesive is selected from the group consisting of:

[0026] Silicone thermal conductive adhesive, epoxy resin AB adhesive, acrylic thermal conductive adhesive, and polyurethane thermal conductive adhesive.

[0027] In another embodiment of the present invention, the light-emitting panel includes a plurality of miniature light-emitting diodes, wherein the miniature light-emitting diodes include:

[0028] A light-emitting platform, configured to emit light; and

[0029] Microlenses are constructed to guide light.

[0030] In another embodiment of the invention, the material of the microlens is selected from the group consisting of:

[0031] Silicon oxide (SiOx), silicon nitride (SiNx), titanium oxide (TiOx), and aluminum oxide (AlOx).

[0032] In another embodiment of the present invention, the miniature light-emitting diode further includes:

[0033] The driving backplane has a metal layer on its surface and a plurality of IC copper pillars disposed on the driving backplane. The IC copper pillars are electrically connected to the metal layer. The micro light-emitting diode array region is bonded to the driving backplane through a bottom conductive bonding layer. The micro light-emitting diode array region includes a plurality of semiconductor light-emitting mesa, each semiconductor light-emitting mesa corresponding to an IC copper pillar. The semiconductor light-emitting mesa includes a first epitaxial layer, a light-emitting layer and a second epitaxial layer deposited sequentially.

[0034] At least one first electrode is electrically connected to the copper pillar of the IC;

[0035] A passivation barrier layer covers the surface of the semiconductor light-emitting mesa, but exposes at least a portion of the second epitaxial layer;

[0036] A transparent conductive layer is disposed on the surface of the passivation barrier layer and is in electrical contact with the first epitaxial layer; and

[0037] The second electrode is disposed on the surface of the transparent conductive layer.

[0038] In another embodiment of the present invention, the second electrode is a ring-shaped reflective electrode, disposed around the semiconductor light-emitting mesa.

[0039] In another embodiment of the invention, the polarity of the second electrode is opposite to that of the first electrode.

[0040] In another embodiment of the present invention, the material of the second epitaxial layer is a material layer of the second conductivity type comprising at least two or more elements of Ga, N, As, Al, In, and P, and the first epitaxial layer is a material layer of the first conductivity type comprising at least two or more elements of Ga, N, As, Al, In, and P, wherein the first conductivity type is different from the second conductivity type.

[0041] In another embodiment of the present invention, the light-emitting layer includes a multi-quantum-well layer, wherein the multi-quantum-well layer is an InGaN / GaN multi-quantum-well layer, an InGaN / AlGaN multi-quantum-well layer, or an InGaAs / AlGaAs multi-quantum-well layer.

[0042] In another embodiment of the present invention, an electron blocking layer is provided on the first side of the light-emitting layer, wherein the first side refers to the side along which electrons migrate out of the light-emitting layer.

[0043] In another embodiment of the present invention, the material of the metal layer is one or more alloys of the following metals: Ni, Al, Ti, Ni, Pt, Au.

[0044] In another embodiment of the present invention, the material of the passivation barrier layer is a SiO2 film or an Al2O3 film.

[0045] In a second aspect of the invention, the aforementioned task is accomplished by a light source machine, the light source machine comprising:

[0046] The light-emitting unit according to the present invention; and

[0047] Multiple coupling lenses are arranged on the window, each of which is configured to transmit light generated by the light-emitting panel.

[0048] In one embodiment of the present invention, the at least two light-emitting panels include:

[0049] A first light-emitting panel is configured to emit a first color of light;

[0050] A second light-emitting panel is configured to emit a second color of light; and

[0051] The third light-emitting panel is configured to emit a third color of light.

[0052] In another embodiment of the present invention, the first and / or second and / or third light-emitting panels are monochromatic light-emitting panels.

[0053] In another embodiment of the invention, the brightness and / or chromaticity of the light source are adjusted by adjusting the brightness of the first and / or second and / or third light-emitting panels.

[0054] In another embodiment of the invention, the first color light is red light, the second color light is green light, and the third color light is blue light; and / or

[0055] The window is either a gap or filled with transparent material to protect the light-emitting panel.

[0056] In a third aspect of the invention, the aforementioned task is accomplished by a near-eye display comprising:

[0057] The light source machine according to the present invention; and

[0058] The housing includes:

[0059] A receiving portion configured to receive the light-emitting panel and the substrate;

[0060] A coupling inlet is provided on the side of the housing opposite to the receiving portion. The coupling inlet is configured to receive the coupling lens and couple the light emitted by the coupling lens into the optical waveguide lens via an optical fiber.

[0061] A lens frame, which extends through the housing and is configured to house the optical waveguide lens; and

[0062] An optical waveguide lens is disposed in the lens outer frame of the housing and configured to output light coupled in from the coupling inlet.

[0063] Furthermore, the present invention also provides a display having a light source according to the present invention. The display may include, for example, a head-mounted display, smart glasses, AR (Augmented Reality) glasses, VR (Virtual Reality) glasses, a smartwatch, a smartphone, etc.

[0064] The present invention has at least the following beneficial effects:

[0065] (1) The present invention provides mixed color light by using three micro light-emitting diode light-emitting panels, which can provide the desired mixed color by using three lower cost light-emitting panels, thereby reducing hardware costs.

[0066] (2) The present invention provides mixed color light by using three micro light-emitting diode light-emitting panels, and the chromaticity and brightness of the output mixed color can be flexibly adjusted by adjusting the brightness of one or more of the light-emitting panels.

[0067] (3) The substrate for external connection of the light-emitting panel in this invention is disposed between the coupling lens and the light-emitting panel via a flip-chip (FC) package, i.e., the three are stacked. Compared with a non-overlapping arrangement of the substrate and the light-emitting panel, this significantly reduces the area occupied by the packaging structure of the light source unit, thereby reducing the size of the light source unit. In addition, by placing the substrate below the coupling lens, a support can be provided for the coupling lens, preventing the coupling lens from directly pressing on the display panel and thus avoiding mechanical damage to it. Furthermore, the window of the substrate allows light from the corresponding light-emitting panel to enter the coupling lens, but the unwindowed portion of the substrate prevents light from adjacent light-emitting panels from entering the current coupling lens, thereby preventing optical crosstalk. Attached Figure Description

[0068] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0069] Figure 1 An exploded view of the components of the light source mechanism after removing the coupling lens and heat sink according to the present invention is shown;

[0070] Figure 2 A schematic diagram of the light source machine according to the present invention is shown;

[0071] Figure 3A and 3B The front and rear views of the light source mechanism according to the present invention after it has been assembled into the housing are shown respectively; and

[0072] Figure 4 A schematic diagram of a miniature light-emitting diode chip in the light-emitting panel of a light source according to the present invention is shown. Detailed Implementation

[0073] In the following description, the invention is described with reference to various embodiments. However, those skilled in the art will recognize that the embodiments may be practiced without one or more specific details or with other alternatives and / or additional methods, materials, or components. In other instances, well-known structures, materials, or operations are not shown or described in detail so as not to obscure the inventive points of the invention. Similarly, for illustrative purposes, specific quantities, materials, and configurations are set forth to provide a comprehensive understanding of embodiments of the invention. However, the invention is not limited to these specific details.

[0074] It should be noted that the components in the various figures may be shown exaggeratedly for illustrative purposes and are not necessarily to scale. In the various figures, the same reference numerals are used for components that are identical or have the same function.

[0075] In this invention, unless otherwise specified, "arranged on," "arranged above," and "arranged on" do not exclude the possibility of an intermediate element between them. Furthermore, "arranged on or above" merely indicates the relative positional relationship between two components, and in certain cases, such as when the product orientation is reversed, it can also be converted to "arranged below or under," and vice versa.

[0076] In this invention, the various embodiments are merely intended to illustrate the solutions of the invention and should not be construed as limiting.

[0077] In this invention, unless otherwise specified, the quantifiers “a” and “one” do not exclude scenarios involving multiple elements.

[0078] In this invention, the term "connection" can refer to a direct connection between two things or an indirect connection between two things through an intermediate element.

[0079] In this application, the term "configuration" refers to setting the shape, structure, material and / or function of a target object to achieve a desired technical effect. "Configuration" includes a variety of alternative technical means to achieve the technical effect, which become apparent from the teachings of this application.

[0080] In this specification, references to "an embodiment" or "this embodiment" mean that a particular feature, structure, or characteristic described in connection with that embodiment is included in at least one embodiment of the invention. The phrase "in one embodiment" appearing throughout this specification does not necessarily refer to the same embodiment in all instances.

[0081] It should be noted that the embodiments of the present invention describe the process steps in a specific order; however, this is only for illustrating the specific embodiment and not for limiting the order of the steps. On the contrary, in different embodiments of the present invention, the order of the steps can be adjusted according to the process.

[0082] Figure 1 An exploded view of the components of the light source 100 after removing the coupling lens and heat sink according to the present invention is shown.

[0083] like Figure 1 As shown, the light source 100 according to the present invention, after removing the coupling lens and heat sink, includes a light-emitting panel 101 and a substrate 3. The above components are described in detail below.

[0084] • One or more light-emitting panels, wherein the light-emitting panels may include a single light-emitting panel or multiple light-emitting panels, such as three light-emitting panels. In the case of three light-emitting panels, the light-emitting panels include:

[0085] A first light-emitting panel 101 is configured to emit a first color of light. The first color of light is, for example, monochromatic light, such as red light. It should be noted that this is merely exemplary, and other light-emitting panels emitting monochromatic or mixed light are conceivable under the teachings of this invention.

[0086] The second light-emitting panel 102 is configured to emit a second color of light. The second color of light is, for example, monochromatic light, such as green light. It should be noted that this is merely exemplary, and other monochromatic or mixed-color light-emitting panels are conceivable under the teachings of this invention.

[0087] The third light-emitting panel 103 is configured to emit a third color of light. This third color of light is, for example, monochromatic light, such as blue light. It should be noted that this is merely exemplary, and other monochromatic or mixed-color light-emitting panels are conceivable under the teachings of this invention.

[0088] Each light-emitting panel may include a miniature light-emitting diode array 2 and a driving backplane 1. The miniature light-emitting diode array 2 is configured to emit light. The driving backplane 1 carries the miniature light-emitting diode array 2 and is configured to drive the miniature light-emitting diode array 2. Further details regarding the miniature light-emitting diode array 2 and the driving backplane 1 can be found in [reference needed]. Figure 4 And its description.

[0089] A substrate 3 has windows 4 formed on it, each window 4 being aligned with at least one light-emitting panel 101-103. Here, each window 4 is aligned with one light-emitting panel 101-103. The window 4 can be a void (filled with air or a protective gas, such as nitrogen, helium, argon, etc.) or filled with a transparent material to protect the light-emitting panel 4. Transparent materials may include, for example, silicon oxide (SiOx), silicon nitride (SiNx), titanium oxide (TiOx), and aluminum oxide (AlOx).

[0090] The substrate 3 can be a printed circuit board, especially a flexible printed circuit board, on which traces for electrical connection are provided. A connector 6 is also provided on the substrate 3. In this embodiment, it is located on the side of the substrate 4 facing the light-emitting panels 101-103; however, in other embodiments, the connector 6 may also be located on the side facing the light-emitting panels 101-103. Conductive lines, such as traces, are provided in or on the substrate 3 to electrically connect the light-emitting panel 1 to the connector 6. The connector 6 can be, for example, a gold finger or contact, such as a contact tip, contact plate, or contact pin.

[0091] Substrate 3 is electrically connected to the light-emitting panels 101-103 via flip-chip (FC) packaging. The specific packaging method is as follows:

[0092] A first contact portion (not shown) is provided on the substrate 3, which is disposed on the surface of the substrate facing the light-emitting panel 101-103 for electrical contact between the circuits of the substrate 3 and the solder balls 8. A solder ball 8 is disposed on the first contact portion, configured to electrically connect the first contact portion to a second contact portion (not shown) disposed on the light-emitting panel 101-103, wherein the second contact portion is used for electrical connection of the light-emitting panel 101-103. A second contact portion is provided on the surface of the drive backplate 1 of the light-emitting panel 101-103 facing the substrate 3, and a solder post 9 is disposed on the second contact portion for electrical contact with the solder ball 8. The solder post 9 and the solder ball 8 are preferably electrically connected to each other by soldering. The material of the solder post 9 and the solder ball is, for example, solder, such as tin or lead, but the material can also be other than solder, such as metal, such as copper, aluminum, etc. The first contact portion and / or the second contact portion may include a through-hole contact portion and a contact point, wherein when the first contact portion and / or the second contact portion is configured to lead out lines inside the substrate 3 or the drive back plate 1, the first contact portion and / or the second contact portion is a through-hole contact portion that passes through at least a portion of the thickness of the substrate 3 or the drive back plate 1, and includes a through-hole and a conductor that is at least partially filled in the through-hole; when the first contact portion and / or the second contact portion is configured to lead out lines on the surface of the substrate 3 or the drive back plate 1, the first contact portion and / or the second contact portion is a contact point disposed on its surface, such as a contact tip, contact piece, contact pin, etc.

[0093] By mounting substrate 3 in a flip-chip (FC) package on coupling lens 5 (see...) Figure 2 The substrate 3 and the light-emitting panels 101-103 are arranged in an overlapping manner. Compared with the non-overlapping arrangement of the substrate 3 and the light-emitting panels (i.e., the substrate is placed on the side of the light-emitting panels), this significantly reduces the area occupied by the packaging structure of the light source, thereby reducing the size of the light source. In addition, by placing the substrate 3 below the coupling lens 5, a support can be provided for the coupling lens 5, preventing the coupling lens 5 from directly pressing on the display panels 101-103, thus avoiding mechanical damage to them. Furthermore, the window 4 of the substrate 3 allows light from the corresponding light-emitting panels 101-103 to enter the coupling lens 5, but the unwindowed portion of the substrate 4 (i.e., the portion outside the window 4 is opaque) prevents light from adjacent light-emitting panels 101-103 from entering the current coupling lens 5, thereby preventing light crosstalk.

[0094] Figure 2 A schematic diagram of a light source 100 according to the present invention is shown.

[0095] Figure 2 The light source 100 shown in the figure and Figure 1 The difference between the two is that the light source machine is... Figure 2 In the middle, multiple coupling lenses 5 and heat sinks 10 are mounted on the light source 100, and Figure 1 The solder balls 8 and solder pillars 9 are joined together to form a conductive connection 7. This joining method can be adhesive bonding, welding, hot melting, hot pressing, shape fitting, force fitting, etc. Specific descriptions of the coupling lens 5 and the heat sink 10 are as follows:

[0096] The light source 100 has multiple coupling lenses 5 arranged on the window 4, each coupling lens 5 configured to transmit light generated by the light-emitting panels 101-103. In this embodiment, three coupling lenses 5 are configured to couple light (e.g., red, green, and blue light) emitted from one of the light-emitting panels 101-103 into an optical fiber (not shown), and then output the light to a lens via the optical fiber. The coupling lens 5 may include, for example, one or more lenses and / or optical waveguides, wherein the lenses are used to shape the light to, for example, form converging or parallel light (e.g., small-angle parallel light, i.e., the angle between the light and the optical axis does not exceed 8° to achieve an increased light spot), and the optical waveguides are used to couple the light output from the lenses into the optical fiber. The optical waveguides may be, for example, optical conductors directly optically connected to the lenses, or optical conductors in the optical path of the light. The coupling lens 5 and the optical conductor may include, for example, quartz glass (mainly made of SiO2), composite glass (mainly made of oxides such as SiO2, Na2O, and CaO), silicate glass, fluoride glass, etc. Optical fibers can include, for example, silica glass optical fibers (the main material is SiO2), composite optical fibers (the main materials are oxides such as SiO2, Na2O and CaO), silicate optical fibers, fluoride optical fibers, plastic-clad optical fibers, all-plastic optical fibers, liquid-core optical fibers, etc.

[0097] The light source unit 100 includes a heat sink 10 disposed on the back side of the light-emitting panels 101-103, i.e., the side of its driving back plate 1 facing away from the substrate 3, and spaced apart from the light-emitting panels 1 and its driving back plate 1. A thermally conductive adhesive 11 is disposed between the heat sink 10 and the light-emitting panels 101-103 and its driving back plate 1 to dissipate heat generated by the light-emitting panels 101-103. The advantage of arranging the heat sink 10 and the light-emitting panels 101-103 and its driving back plate 1 separately is that, when the heat sink is an electrical conductor such as metal, it can prevent abnormal conductivity such as short circuits or leakage caused by electrical contact between the driving circuit 1 and the heat sink 10. In other words, the spaced arrangement prevents electrical contact between the two, while thermal contact between them is achieved by the thermally conductive adhesive 11. Materials for the thermally conductive adhesive 11 include, for example, silicone thermally conductive adhesive, epoxy resin AB glue, acrylic thermally conductive adhesive, and polyurethane thermally conductive adhesive. In addition, thermally conductive adhesive can be filled between the heat sink 11 and the substrate 3 to dissipate heat from the substrate 3, or the heat dissipation effect can be improved by surrounding the light-emitting panel 101-103 with thermally conductive adhesive 11.

[0098] Figure 3A and 3BThe front and rear views of the light source according to the present invention after it has been assembled into the housing are shown respectively.

[0099] The housing 14 of the light source according to the present invention includes the following components:

[0100] • Receiving portion 15 is configured to receive the light-emitting panel and the substrate. Here, the receiving portion 15 is configured as an open recess, such that when the light-emitting panel and the substrate are inserted, the open recess can expose at least a portion of the back side of the inserted component, such as the connector 6, the heat sink 11, and the substrate 3, thereby facilitating electrical connection and promoting heat dissipation. At the same time, the open recess also facilitates the replacement of the display component.

[0101] A coupling inlet 12 is located on the side of the housing 14 opposite to the receiving portion 15. The coupling inlet 12 is configured to receive the coupling lens 5 and couple the light emitted from the coupling lens 5 into the optical waveguide lens 14 via an optical fiber (not shown). The coupling inlet 12 is, for example, constructed to fit the shape of the coupling lens 5 so as to stably fix it within the housing 14. In other applications, coupling inlets of other shapes are also conceivable, such as square, polygonal, or irregular shapes.

[0102] A lens frame 13 penetrates the housing 1 and is configured to accommodate the optical waveguide lens 14. The lens frame 13 is, for example, a rectangular notch opened in the housing 14, the four corners of which may be rounded. Preferably, the lens frame 13 has a snap-fit ​​structure for mounting the lens, such as a slot. The lens frame 13 can penetrate the housing 13 to suit applications such as smart glasses. That is, light can be transmitted from one side of the optical waveguide lens 14 to the other side and continue to propagate.

[0103] • An optical waveguide lens 14 is disposed within the lens frame 13 of the housing 14 and configured to output light coupled in from the coupling inlet 12. For example, the optical waveguide lens 14 is used to overlay an image output from the light source 100 onto the optical waveguide lens 14 to provide a user experience such as AR or VR. The material of the optical waveguide lens 14 may include, for example, quartz glass (primarily SiO2), plexiglass, composite glass (primarily oxides such as SiO2, Na2O, and CaO), silicate glass, fluoride glass, etc.

[0104] The main material of the housing 14 may include, for example, plastic, wood, glass, metal, ceramic, etc. Different housing materials can be selected according to different scenarios to meet requirements such as insulation, thermal conductivity, mechanical strength, and weight.

[0105] By mounting substrate 3 in a flip-chip (FC) package on coupling lens 5 (see...) Figure 2The substrate 3 and the light-emitting panels 101-103 are arranged in an overlapping manner. Compared with the arrangement where the substrate 3 and the light-emitting panels do not overlap (i.e., the substrate is arranged on the side of the light-emitting panel), the area occupied by the packaging structure of the light source can be significantly reduced, thereby reducing the size of the light source. This, in turn, reduces the size of the receiving portion 15 of the packaging structure in the housing 14 for arranging the light-emitting panels. Furthermore, the frame of the housing 14 can be narrowed or shortened, thereby reducing the size of the corresponding device (such as smart glasses).

[0106] Furthermore, the present invention also provides a display having a light source according to the invention. The display may include, for example, a head-mounted display, smart glasses, AR (Augmented Reality) glasses, VR (Virtual Reality) glasses, a smartwatch, a smartphone, etc. In these devices, by employing the light source according to the invention, the device area can be significantly reduced, which is beneficial to the trend of device miniaturization.

[0107] Figure 4 A schematic diagram of a miniature light-emitting diode chip according to the present invention is shown.

[0108] like Figure 4 As shown, the miniature light-emitting diode chip in the light-emitting panel 101-103 of the light source includes the following components:

[0109] The substrate 601 may be made of materials such as ceramic, quartz glass, silicate glass, soda-lime glass, fluoride glass, silicon oxide, or silicon nitride. For example, using a ceramic substrate to support the micro-LED chip can improve the substrate's mechanical strength, thus providing better protection for the micro-LED chip. Furthermore, compared to silicon substrates, ceramics offer better insulation, thereby improving the insulation of the micro-LED chip and preventing leakage current or interference from external currents.

[0110] A driving circuit 602 (i.e., driving backplane 1) is formed on a substrate 601. The driving circuit 602 may be, for example, a thin-film transistor (TFT) driving circuit, and may include a 2T1C driving circuit, a 3T1C driving circuit, and a 5T2C driving circuit. The driving circuit 602 is configured to drive micro-light-emitting diodes (LEDs), for example, controlling the switching on, off, and brightness of the micro-LEDs. The driving circuit 602 may include, for example, transistors, capacitors, a conductive line layer, an insulating layer, and a metal layer. The conductive line layer is formed on the substrate and configured to supply power to the micro-LED array. An insulating layer is formed on the conductive line layer, wherein through-holes are provided in the insulating layer, and through-hole contacts (e.g., IC copper pillars) are provided in the through-holes for electrically connecting the conductive line layer to the micro-LED array. The metal layer is used for bonding and electrically contacting the micro-LEDs. The conductive circuit layer, metal layer, and insulating layer can be formed on the substrate 601 by deposition, such as physical vapor deposition (PVD) and chemical vapor deposition (CVD). Depending on the specific application, the metal layer and insulating layer can be patterned by photolithography and vias can be formed on them. Furthermore, transistors and capacitors in the conductive circuit layer can be formed by deposition and etching.

[0111] A micro-LED array 603 includes an epitaxial layer 608. The micro-LED array 603 is formed on a driving circuit 603 or a substrate 601. The specific structure of the epitaxial layer is described below. The micro-LED array 603 is bonded to the driving circuit 602 or the substrate 601 by bonding, including full-surface bonding and hybrid bonding. In some embodiments, the micro-LED array may include blue micro-LEDs. In some embodiments, the spacing of the micro-LED array, i.e., the minimum center-to-center distance between the micro-LEDs, may be between about 2 micrometers and about 50 micrometers. In some embodiments, the number of pixels on the micro-LED chip 100 may be between several thousand and several million.

[0112] Each miniature light-emitting diode includes the following components:

[0113] An epitaxial layer 608 is configured to emit light. The epitaxial layer includes a first epitaxial layer, a second epitaxial layer, and a light-emitting layer disposed between the first and second epitaxial layers. The epitaxial layer 108 comprises a first epitaxial layer, a light-emitting layer, and a second epitaxial layer deposited sequentially, wherein the light-emitting layer includes a multiple quantum well layer and an electron blocking layer. In one embodiment of the invention, the first epitaxial layer is an N-type GaN layer or an N-type AlGaN layer, and the second epitaxial layer is a P-type GaN layer or a P-type AlGaN layer. That is, the material of the second epitaxial layer can be a material layer of a second conductivity type comprising at least two or more elements of Ga, N, As, Al, In, and P, and the first epitaxial layer can be a material layer of a first conductivity type comprising at least two or more elements of Ga, N, As, Al, In, and P. The multiple quantum well layer is an InGaN / GaN multiple quantum well layer, an InGaN / AlGaN multiple quantum well layer, or an InGaAs / AlGaAs multiple quantum well layer. The electron blocking device is disposed on a first side of the light-emitting layer, where the first side refers to the side along which electrons migrate out of the light-emitting layer. In another embodiment of the present invention, the first epitaxial layer may also be a P-type GaN layer or a P-type AlGaN layer, and the second epitaxial layer may be an N-type GaN layer or an N-type AlGaN layer.

[0114] The first electrode, such as cathode 611, is electrically connected to the first epitaxial layer of epitaxial layer 603 via transparent conductive layer 609 and cathode contact portion 114 passing through passivation layer 615. Cathode 611 can be a ring-shaped reflective electrode, disposed around epitaxial layer 608, and can be formed, for example, by magnetron sputtering or vapor deposition. Its material can be, for example, Al or Al alloy metal for the sidewall reflective surface, and the electrode stack metal can be Ni, Al, Ti, Pt, Au, or other metal materials. Passivation layer 115 is disposed between transparent conductive layer 609 and epitaxial layer 608. Its function is not only to reduce current leakage at the sidewalls, but also to passivate sidewall defects and prevent damage to the light-emitting mesa from water, oxygen, etc., during operation. Passivation layer 114 can be formed by depositing SiO2 material using CVD process or by depositing Al2O3 material using ALD process. Cathode 111 can be, for example, a common cathode structure, i.e., an array of micro-light-emitting diodes connected to a common cathode. It should be noted that in some embodiments, the cathode and anode may be interchanged and this also falls within the scope of the present invention.

[0115] A second electrode, such as anode 613, is disposed at the bottom of epitaxial layer 608 to power anode 613. The anode 613 of each array of micro-LEDs can be selectively connected to signal contact 612. The common cathode and selective anode connection can form a passive matrix control method to control the on / off state and brightness adjustment of each micro-LED. Additional layers, such as passivation layer 615, transparent conductive layer 609, cathode 611, etc., are also provided on epitaxial layer 608 and anode 613. Furthermore, signal contacts 612 are formed on the sides for leading out the anode 613 of the corresponding micro-LED. It should be noted that in some embodiments, the cathode and anode can be interchanged and this also falls within the scope of the invention.

[0116] Multiple miniature light-emitting diodes (LEDs) constitute a miniature LED array, and multiple miniature LED arrays in turn constitute a miniature LED chip. Each miniature LED chip is no larger than 1 cm, and the size of each miniature LED is preferably no larger than 2050 micrometers. The miniature LED structure is formed in an array within the miniature LED chip, achieving printing resolutions such as 1200 DPI, 600 DPI, and resolutions such as 720*480, 640*480, 1920*1080, 1280*720, 2K, or 4K. The diameter of the miniature LED structure is in the nanometer / micrometer range, for example, from 20 nm to 100 to 50 nm.

[0117] While some embodiments of the invention have been described in this application, those skilled in the art will understand that these embodiments are merely illustrative. Numerous variations, alternatives, and improvements will arise in those skilled in the art under the teachings of this invention without departing from its scope. The appended claims are intended to define the scope of the invention and thereby cover methods and structures within the scope of the claims themselves and their equivalents.

Claims

1. A light-emitting unit, comprising: At least two light-emitting panels are configured to emit light; as well as A substrate having windows, each window being aligned with at least one light-emitting panel.

2. The light source machine as claimed in claim 1, wherein the substrate is electrically connected to the light-emitting panel via a flip-chip package.

3. The light-emitting unit as claimed in claim 2, wherein the substrate comprises: A first contact portion is disposed on the surface of the substrate facing the light-emitting panel for electrical contact between the circuits of the substrate and the solder balls. as well as Solder ball, configured to electrically connect a first contact portion to a second contact portion disposed on the light-emitting panel, wherein the second contact portion is used for electrical connection of the light-emitting panel.

4. The light-emitting unit as claimed in claim 2, wherein the light-emitting panel comprises: A miniature array of light-emitting diodes configured to emit light; as well as A driving backplane that carries the micro LED array and is configured to drive the micro LED array, wherein a second contact portion is disposed on the driving backplane.

5. The light-emitting unit as claimed in claim 4, wherein a welding post is provided between the second contact portion and the welding ball for electrical connection between the welding ball and the second contact portion.

6. The light-emitting unit as claimed in claim 3, wherein the first contact portion and / or the second contact portion comprises at least one of the following: Through-hole contact portion and contact point.

7. The light-emitting unit as described in claim 1, further comprising: A connector is disposed on the substrate to connect the light-emitting panel to an external control source or an external power supply.

8. The light-emitting unit as described in claim 4, wherein the driving backplates are spaced apart, and each micro light-emitting diode array is spaced apart on the corresponding driving backplate.

9. The light-emitting unit of claim 7, wherein the connector comprises at least one of the following: Gold fingers and stitches.

10. The light-emitting unit as claimed in claim 1, further comprising: A heat sink is disposed on the back side of the light-emitting panel and spaced apart from the light-emitting panel, wherein thermally conductive adhesive is disposed between the heat sink and the light-emitting panel to dissipate the heat generated by the light-emitting panel.

11. The light-emitting unit of claim 10, wherein a thermally conductive adhesive is disposed between the heat sink and the substrate to dissipate the heat generated by the substrate.

12. The light-emitting unit of claim 10, wherein the material of the thermally conductive adhesive is selected from the group consisting of: Silicone thermal conductive adhesive, epoxy resin AB adhesive, acrylic thermal conductive adhesive, and polyurethane thermal conductive adhesive.

13. The light-emitting unit as claimed in claim 1, wherein the light-emitting panel comprises a plurality of miniature light-emitting diodes, wherein the miniature light-emitting diodes comprise: A light-emitting platform, configured to emit light; as well as Microlenses are constructed to guide light.

14. The light-emitting unit of claim 13, wherein the material of the microlens is selected from the group consisting of: Silicon oxide (SiOx), silicon nitride (SiNx), titanium oxide (TiOx), and aluminum oxide (AlOx).

15. The light-emitting unit of claim 13, wherein the miniature light-emitting diode further comprises: The driving backplane has a metal layer on its surface and a plurality of IC copper pillars disposed on the driving backplane. The IC copper pillars are electrically connected to the metal layer. The micro light-emitting diode array region is bonded to the driving backplane through a bottom conductive bonding layer. The micro light-emitting diode array region includes a plurality of semiconductor light-emitting mesa, each semiconductor light-emitting mesa corresponding to an IC copper pillar. The semiconductor light-emitting mesa includes a first epitaxial layer, a light-emitting layer and a second epitaxial layer deposited sequentially. At least one first electrode is electrically connected to the copper pillar of the IC; A passivation barrier layer is applied to the surface of the semiconductor light-emitting mesa, but at least a portion of the second epitaxial layer is exposed. A transparent conductive layer is disposed on the surface of the passivation barrier layer and is in electrical contact with the first epitaxial layer; as well as The second electrode is disposed on the surface of the transparent conductive layer.

16. The light-emitting unit of claim 15, wherein the second electrode is an annular reflective electrode disposed around the semiconductor light-emitting mesa.

17. The light-emitting unit of claim 15, wherein the polarity of the second electrode is opposite to that of the first electrode.

18. The light-emitting unit of claim 15, wherein the material of the second epitaxial layer is a material layer of a second conductivity type comprising at least two or more elements including Ga, N, As, Al, In, and P, and the first epitaxial layer is a material layer of a first conductivity type comprising at least two or more elements including Ga, N, As, Al, In, and P, wherein the first conductivity type is different from the second conductivity type.

19. The light-emitting unit of claim 15, wherein the light-emitting layer comprises a multi-quantum well layer, wherein the multi-quantum well layer is an InGaN / GaN multi-quantum well layer, an InGaN / AlGaN multi-quantum well layer, or an InGaAs / AlGaAs multi-quantum well layer.

20. The light-emitting unit of claim 15, wherein an electron blocking layer is provided on a first side of the light-emitting layer, the first side referring to the side along which electrons migrate out of the light-emitting layer.

21. The light-emitting unit as claimed in claim 15, wherein the material of the metal layer is one or more alloys of the following metals: Ni, Al, Ti, Ni, Pt, Au.

22. The light-emitting unit as claimed in claim 15, wherein the material of the passivation barrier layer is a SiO2 film or an Al2O3 film.

23. A light source machine, comprising: The light-emitting unit as described in any one of claims 1 to 22; as well as Multiple coupling lenses are arranged on the window, each of which is configured to transmit light generated by the light-emitting panel.

24. The light source machine of claim 23, wherein the at least two light-emitting panels comprise: A first light-emitting panel is configured to emit a first color of light; The second light-emitting panel is configured to emit a second color of light; as well as The third light-emitting panel is configured to emit a third color of light.

25. The light source machine as claimed in claim 24, wherein the first and / or second and / or third light-emitting panels are monochromatic light-emitting panels.

26. The light source machine of claim 25, wherein the brightness and / or chromaticity of the light source are adjusted by adjusting the brightness of the first and / or second and / or third light-emitting panels.

27. The light source as claimed in claim 24, wherein the first color light is red, the second color light is green, and the third color light is blue; and / or The window is either a gap or filled with transparent material to protect the light-emitting panel.

28. A near-eye display, comprising: The light source machine as described in any one of claims 23 to 27; as well as The housing includes: A receiving portion configured to receive the light-emitting panel and the substrate; A coupling inlet is provided on the side of the housing opposite to the receiving portion. The coupling inlet is configured to receive the coupling lens and couple the light emitted by the coupling lens into the optical waveguide lens via an optical fiber. A lens frame, which extends through the housing and is configured to house the optical waveguide lens; and An optical waveguide lens is disposed in the lens outer frame of the housing and configured to output light coupled in from the coupling inlet.

29. A display having a light source as described in any one of claims 23 to 27.

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