CN111883627A

CN111883627A - Light emitting device

Info

Publication number: CN111883627A
Application number: CN202010017160.2A
Authority: CN
Inventors: 胡顺源; 丁景隆; 高克毅; 毛立维
Original assignee: Innolux Corp
Current assignee: Innolux Corp
Priority date: 2019-05-02
Filing date: 2020-01-08
Publication date: 2020-11-03

Abstract

The application provides a light emitting device, which comprises a light emitting unit and an optical layer. The light emitting unit includes a light emitting chip and a package structure disposed on the light emitting chip. The optical layer is disposed on the light emitting unit, and has a first region overlapping with the light emitting chip in a top view direction of the light emitting device, and a second region not overlapping with the light emitting chip in the top view direction of the light emitting device, wherein a transmittance of the first region is smaller than a transmittance of the second region.

Description

Light emitting device

Technical Field

The present disclosure relates to a light emitting device, and more particularly, to a light emitting diode light emitting device.

Background

In recent years, light-emitting diodes (LEDs) have been widely used, but problems such as the light intensity decreasing too fast with the viewing angle still need to be overcome. Therefore, developing a structure design of a light emitting device capable of further improving the efficiency of the light emitting diode is still one of the issues of research in the industry at present.

Disclosure of Invention

Drawings

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below, wherein:

FIG. 1A is a schematic diagram of some elements of a light emitting device according to some embodiments of the present application.

Fig. 1B and 1C are schematic cross-sectional views illustrating a light emitting chip according to some embodiments of the present disclosure.

Fig. 2A and 2B are schematic diagrams illustrating a relationship between the light-emitting intensity and the viewing angle of the light-emitting unit in the present application.

Fig. 3A to 3C are schematic views of a light emitting device according to some embodiments of the present disclosure.

FIG. 4 is a schematic illustration of some embodiments of the present application.

Fig. 5A-5D are top views of some embodiments of the present application.

Fig. 6A and 6B are top views of some embodiments of the present application.

FIG. 7 is a schematic illustration of some embodiments of the present application.

FIG. 8 is a graphical representation of the reflectivity of the optical layer at various locations according to some embodiments of the present application.

Fig. 9A and 9B are schematic views of some elements of a light emitting device according to some embodiments of the present disclosure.

Fig. 10A to 10E are schematic views of some elements of a light emitting device according to some embodiments of the present application.

FIG. 11 is a schematic view of some elements of a light emitting device according to some embodiments of the present application.

FIG. 12 is a schematic view of some elements of a light emitting device according to some embodiments of the present application.

Element numbering in the figures:

1. 2A, 2B, 2C, 3A, 3B, 4A, 4B, 4C, 4D, 4E, 5, 6 light-emitting device

10. 12 substrate

20. 20A, 20B, 20C light emitting unit

22 packaging substrate

24. 25 packaging structure

26 luminous chip group

26A, 26B, 26C, 27 light emitting chip

30. 30A, 30B, 30C, 30D, 30E optical layers

31A, 31B optical material

32A, 32B, 32C holes

34A, 34B, 34C, 36A, 36B, 36C gap

38A, 38B, 38C light blocking pattern

40 optical film

42 display layer

44 wavelength conversion layer

50 reflective layer

60 light guide layer

70 anti-reflection layer

B1, B2, B3 backlight unit

R1 first region

R2 second region

Maximum thickness of T1 and T2

Detailed Description

Various embodiments or examples are disclosed below to practice various features of the provided subject matter, and embodiments of specific elements and arrangements thereof are described below to illustrate the present application. These examples are, of course, intended to be illustrative only and should not be construed as limiting the scope of the application. For example, if a first feature is formed over a second feature in the description, that may include embodiments in which the first feature is in direct contact with the second feature, embodiments in which additional features may be included between the first feature and the second feature, that is, the first feature and the second feature may not be in direct contact.

Moreover, where specific reference numerals or designations are used in various embodiments, these are merely used to identify the invention in a simplified and clear manner, and do not necessarily indicate a particular relationship between the various embodiments and/or structures discussed. Furthermore, forming over, connecting to, and/or coupling to another feature in this application may include embodiments in which the features are formed in direct contact, and may also include embodiments in which additional features may be formed interposing the features described above, such that the features may not be in direct contact. Furthermore, spatially relative terms, such as "vertical," "above," "upper," "lower," "bottom," and the like, may be used herein to describe one element or feature's relationship to another element or feature(s) in the figures and are intended to encompass different orientations of the device in which the feature is included.

As used herein, the term "about", "about" or "substantially" generally means within 20%, or within 10%, or within 5%, or within 3%, or within 2%, or within 1%, or within 0.5% of a given value or range. The amounts given herein are approximate, that is, the meanings of "about", "about" and "substantially" may be implied without specifically stating "about", "about" or "substantially".

Furthermore, in some embodiments of the present application, terms such as "connected," "interconnected," and the like, with respect to bonding, connecting, and the like, may refer to two structures being in direct contact, or may also refer to two structures not being in direct contact, unless otherwise specified, with other structures being interposed between the two structures. And the terms coupled and connected should also be construed to include both structures being movable or both structures being fixed.

Furthermore, the terms "in a range of a first value to a second value" and "in a range of a first value to a second value" mean that the range includes the first value, the second value, and other values therebetween.

Fig. 1A is a schematic diagram of some elements of a light emitting device 1 according to some embodiments of the present application. The light emitting device 1 according to some embodiments of the present disclosure may include a portion of a flexible display device (flexible display), a touch display device (touch display), a curved display device (curved display), or a non-rectangular display device (free shape display), but the present disclosure is not limited thereto. In some embodiments, the light emitting device 1 may mainly include a substrate 10, a plurality of light emitting units 20 disposed on the substrate 10, and an optical layer 30 disposed on the light emitting units 20.

In some embodiments, the substrate 10 may be an array substrate, for example, may serve as a driving substrate for the light emitting unit 20. In detail, the substrate 10 may include a Thin-Film Transistor (TFT) or a driving circuit (not shown), but is not limited thereto. Wherein the driving circuit can be, for example, an active driving circuit or a passive driving circuit. According to some embodiments, the driving circuit may include a transistor (e.g., a switching transistor or a driving transistor, etc.), a data line, a scan line, a conductive pad, a dielectric layer, or other lines, etc., but is not limited thereto. The switching transistor may be used to control the switching of the light emitting cell 20. In some embodiments, the driving circuit may be coupled to an Integrated Circuit (IC) or a microchip, etc. to control the light emitting unit 20.

In some embodiments, the material of the substrate 10 may include glass, quartz, sapphire (sapphire), Polycarbonate (PC), Polyimide (PI), polyethylene terephthalate (PET), rubber, fiberglass, ceramic, other suitable materials, or a combination of the foregoing, but is not limited thereto. In some embodiments, the substrate 10 may include a metal-glass fiber composite board, a metal-ceramic composite board (PCB), a Flexible Printed Circuit (FPC), and the like, and is not limited thereto.

In some embodiments, the light emitting unit 20 may be used as a light source required by the light emitting device 1, and may mainly include a package substrate 22, a package structure 24 disposed on the package substrate 22, and a light emitting chip group 26 disposed in the package structure 24. The material of the package substrate 22 may be, for example, BT Resin (bis imide Triazine Resin), Polyimide (PI), Epoxy Resin (Epoxy) glass fiber, ceramic, etc., but the present application is not limited thereto. In some embodiments, circuitry may be provided in the package substrate 22 to electrically connect the light emitting chip set 26 with the substrate 10 through the package substrate 22. The material of the package structure 24 may be, for example, silicon (silicon), Epoxy resin (Epoxy resin), or the like, but the present application is not limited thereto. The package structure 24 can serve as a protection layer for protecting the light emitting chip set 26 disposed therein.

In some embodiments, the package structure 24 may be formed by a chemical vapor deposition process, a coating process, a printing process, an inkjet printing process, a die forming process, or other suitable methods or combinations thereof. Alternatively, the package structure 24 may be formed by one or more photolithography processes and etching processes.

In some embodiments, the light emitting chip set 26 may include a plurality of light emitting chips (e.g., the

light emitting chips

26A, 26B, and 26C shown in fig. 1A), which may respectively emit lights of the same or different colors (e.g., red, green, blue, and white lights), but the present application is not limited thereto. In some embodiments, the

light emitting chips

26A, 26B, 26C may include organic light-emitting diodes (OLEDs), quantum dot light-emitting diodes (QLEDs/QDLEDs), light-emitting diodes (LEDs), and the like; the light emitting diode may include micro LED or mini LED.

Referring to fig. 1B and 1C, fig. 1B and 1C show cross-sectional views of a light emitting chip 26A (or light emitting

chips

26B and 26C) according to some embodiments of the present disclosure. As shown in fig. 1B, the light emitting chip 26A may be a light emitting chip having a vertical type structure (vertical type) according to some embodiments. According to other embodiments, as shown in fig. 1C, the light emitting chip 26A may be a flip-chip type light emitting chip. The present application is not so limited.

Specifically, the light emitting chip 26A (or the

light emitting chips

26B, 26C) may include a first semiconductor layer 261, a second semiconductor layer 262, and an active layer 263. The active layer 263 may be disposed between the first semiconductor layer 261 and the second semiconductor layer 262. In some embodiments, one of the first semiconductor layer 261 and the second semiconductor layer 262 may be used for providing and/or transporting electrons, while the other may be used for providing and/or transporting holes. In some embodiments, the first semiconductor layer 261 and the second semiconductor layer 262 may be formed by a semiconductor material having an n-type conductivity and a semiconductor material having a p-type conductivity, respectively. However, in other embodiments, the first semiconductor layer 261 and the second semiconductor layer 262 may be formed by a semiconductor material having a p-type conductivity and a semiconductor material having an n-type conductivity, respectively.

In some embodiments, the n-type conductivity type semiconductor material may include gallium nitride (n-GaN) or aluminum indium phosphide (n-AlInP) doped with tetravalent atoms, and the p-type conductivity type semiconductor material may include gallium nitride (p-GaN) or aluminum indium phosphide (p-AlInP) doped with divalent atoms, but the application is not limited thereto. Furthermore, in some embodiments, the active layer 263 may have a quantum well (SQW) structure, for example, a Single Quantum Well (SQW), a Multiple Quantum Well (MQW), a Nanowire (Nanowire), other suitable structures, or a combination of the foregoing. In some embodiments, the material of the active layer 263 may include gallium nitride, aluminum indium phosphide (AlInP), indium gallium nitride (InGaN), or a combination thereof, but is not limited thereto.

In some embodiments, the first semiconductor layer 261, the second semiconductor layer 262 and the active layer 263 may be formed by an epitaxial growth process. The epitaxial growth process may include a Molecular Beam Epitaxy (MBE) process, a Liquid Phase Epitaxy (LPE) process, a Solid Phase Epitaxy (SPE) process, a Vapor Phase Epitaxy (VPE) process, a Selective Epitaxial Growth (SEG) process, a Metal Organic Chemical Vapor Deposition (MOCVD) process, an atomic layer chemical vapor deposition (ALD), or the like, or a combination thereof.

In addition, in some embodiments, the light emitting chip 26A also includes a first electrode layer 264 and a second electrode layer 265 disposed on the first semiconductor layer 261 and the second semiconductor layer 262. Specifically, in the embodiment where the light emitting chip 26A has a vertical structure, the first electrode layer 264 and the second electrode layer 265 are disposed on two opposite sides (as shown in fig. 1B). In the embodiment where the light emitting chip 26A has the flip-chip structure, the first electrode layer 264 and the second electrode layer 265 are disposed on the same side (as shown in fig. 1C).

In some embodiments, the first electrode layer 264 and the second electrode layer 265 can be further electrically connected to a signal line (not shown) or a driving circuit (not shown) of the substrate 10. In some embodiments, the material of the first electrode layer 264 and the second electrode layer 265 can include a conductive metal material. For example, the conductive metal material may include copper (Cu), aluminum (Al), tungsten (W), titanium (Ti), gold (Au), platinum (Pt), nickel (Ni), tin (Sn), indium (In), an alloy of the foregoing metal materials, other suitable conductive materials, or a combination of the foregoing, but is not limited thereto.

In some embodiments, the first electrode layer 264 and/or the second electrode layer 265 may be formed by one or more deposition processes, photolithography processes, and etching processes. In some embodiments, the deposition process may include a chemical vapor deposition process, a physical vapor deposition process, an electroplating process, an electroless plating process, other suitable processes, or a combination thereof. Furthermore, in some embodiments, the photolithography process may include photoresist coating (e.g., spin coating), soft baking, hard baking, mask alignment, exposure, post-exposure baking, photoresist development, cleaning, and drying, etc. In some embodiments, the etching process includes a dry etching process, a wet etching process, or other suitable etching process.

It should be understood that, according to some embodiments, the structure of the light emitting chip 26A may be adjusted according to requirements, or required elements may be additionally disposed on the light emitting chip 26A, and the light emitting chip 26A described herein is not limited to the foregoing structure.

Please refer to fig. 1A. In some implementationsFor example, the optical layer 30 may include a material with high reflectivity (reflectivity), such as a metal or other composite material with different refractive index (refractive index), but the application is not limited thereto. In some embodiments, the metal may include silver, aluminum, gold, nickel, other suitable materials, or combinations thereof, but is not limited thereto, and the composite material may include TiO₂、SiO₂、Nb₂O₅、Ta₂O₅、ZrO₂、Al₂O₃、Y₂O₃MgO, other suitable materials, or combinations of the above materials, but is not limited thereto.

In embodiments where the optical layer 30 is a composite material as described above, the optical layer 30 may be, for example, a Distributed Bragg Reflector (DBR). Specifically, when light passes through different media, reflection occurs at the interface of the different media, wherein the magnitude of the reflectivity is related to the magnitude of the refractive index between the media. Therefore, when thin films having different refractive indexes are alternately and periodically stacked, light reflected by each layer undergoes constructive interference (phase angle) due to a change in phase angle and is then combined, so that the light is reflected, thereby forming a bragg mirror structure. However, the present application is not limited thereto. Different metals with different transmittances (transmission) can be used to form the optical layer 30, and the effect of controlling the reflection or transmission of light can also be achieved.

In some embodiments, the optical layer 30 may also include an omni-directional reflector (ODR) structure. In particular, the internal mirror structure may comprise a dielectric material/metallic reflective material/dielectric material stack. In some embodiments, the dielectric material may comprise silicon oxide (SiO)_x) Silicon nitride (SiN)_x) Silicon oxynitride (SiON), aluminum oxide (Al)₂O₃) Titanium dioxide (TiO)₂) Other suitable materials, or combinations of the foregoing, but the application is not limited thereto. In some embodiments, the metallic reflective material may comprise copper, aluminum, indium, ruthenium, tin, gold, platinum, zinc,Silver, titanium, lead, nickel, chromium, magnesium, palladium, alloys of the foregoing metallic materials, other suitable materials, or combinations of the foregoing materials, but are not limited thereto.

Thereby, a part of the light emitted by the light emitting unit 20 can be reflected by the optical layer 30, and instead, the light is emitted from the side where the optical layer 30 is not disposed, so that the viewing angle of the light emitting device 1 can be changed. For example, fig. 2A and 2B are schematic diagrams illustrating a relationship between the light-emitting intensity and the viewing angle of the light-emitting unit in the present application. The light emitting unit 20 of fig. 2A is not provided with the optical layer 30, while the light emitting unit of fig. 2B has the optical layer 30. In fig. 2A, the light emitting unit 20 has the strongest light emitting intensity at a viewing angle of approximately 0 degrees (i.e., in the top-down direction Z of the substrate 10), and decreases with increasing viewing angle. For the sake of simplicity, in the following description, the term "planar direction of the substrate" will be referred to as "planar direction".

However, in the embodiment of fig. 2B, due to the optical layer 30, light with a smaller viewing angle (close to the top view direction) can be reflected, so that at least a part of the light is emitted from the side where the optical layer 30 is not arranged, i.e. from a position with a larger viewing angle. Therefore, in fig. 2B, the light-emitting intensity of the light-emitting device is not strongest when the viewing angle is 0 degree (parallel to the top view direction), and the light-emitting intensity can increase with the increase of the viewing angle up to a specific angle (for example, about 60 degrees in fig. 2B, but the application is not limited thereto). Then, the light intensity can be reduced as the viewing angle is increased. Therefore, the problem that the light-emitting intensity of the light-emitting unit 20 declines too fast with the increase of the viewing angle can be solved.

In some embodiments, the optical layer 30 may be formed by other suitable methods such as the deposition process, coating process, printing process, inkjet printing process, stamp forming, or combinations thereof. Furthermore, the optical layer 30 may be formed by one or more photolithography processes and etching processes.

Fig. 3A to 3C are schematic views of light emitting

devices

2A, 2B, and 2C according to some embodiments of the present disclosure, respectively. The light-emitting device 2A mainly includes a backlight unit B1 (including the substrate 10, the light-emitting unit 20A, the optical layer 30, the optical film 40), and a display layer 42 provided on the backlight unit B1. For example, the optical Film 40 may be a Prism sheet (Prism Film), a diffusion sheet (diffusion Film), a reflective Brightness Enhancement Film (DBEF), a quantum dot Film (quantumdot Film), or the like, but is not limited thereto. In addition, the optical film 40 may be provided by mechanical means, gluing, or other means. The display layer 42 may selectively include, for example, a Liquid Crystal (LC), a quantum dot (quantum dot), a fluorescent material (fluorescent material), a phosphorescent material (phosphorescent material), an Organic Light Emitting Diode (OLED), or other display medium, or a combination thereof, but the present application is not limited thereto. Additional adhesive material or other mechanical means (not shown) may be provided between the substrate 10 and the optical film 40 to connect or fix the substrate 10 and the optical film 40.

The light emitting unit 20A may have a structure similar to that of the aforementioned light emitting unit 20, but the present application is not limited thereto. For example, in fig. 3B, the light emitting unit 20B of the backlight unit B2 may include a package substrate 22, a package structure 24, and a light emitting chip 27 disposed in the package structure 24. In addition, the backlight unit B2 further includes a wavelength conversion layer 44 disposed on the optical film 40. In some embodiments, the light source provided by the light emitting chip 27 may be short wavelength to visible wavelength range light, for example, the wavelength range may include about 10 nanometers (nm) to about 780 nanometers. However, the present application is not limited thereto, and in some embodiments, the light emitting chip 27 may emit infrared light or far infrared light. In some embodiments, the light source provided by the light emitting chip 27 may include blue light or UV light, and the light emitted by the light emitting chip 27 may be converted into light with a desired wavelength distribution (for example, but not limited to, red light, green light, or white light) by the wavelength conversion layer 44. For example, in some embodiments, the wavelength conversion layer 44 can be patterned and disposed corresponding to the light emitting units 20B to convert the light emitted from different light emitting chips 27 into light with different wavelength distributions. In some embodiments, the positions of optical film 40 and wavelength-converting layer 44 may be interchanged, i.e., wavelength-converting layer 44 may be located between optical film 40 and display layer 42. In some embodiments, the wavelength conversion layer 44 has a filtering function, so that the light emitted by the light emitting chip 27 exhibits a desired wavelength distribution after passing through the wavelength conversion layer 44 by filtering out a part of the wavelength of the light.

However, the present application is not limited thereto. As shown in fig. 3C, the wavelength conversion layer of the foregoing embodiment is not disposed in the backlight unit B3 of the light emitting device 2C, but the package structure 25 including the wavelength conversion medium is used to cover the light emitting chip 27, so that the light emitting unit 20C (including the package substrate 22, the package structure 25, and the light emitting chip 27) directly emits light with a desired wavelength (for example, red light, green light, or white light, but not limited thereto). The backlight units B1, B2, B3 may provide light sources required when the display layer 42 displays images, for example. Similarly, in some embodiments, the package structure 25 also has a light filtering function.

The package structure 25 or the wavelength conversion layer 44 may have a function of converting a wavelength of light, for example, a light source generated by the light emitting chip 27 may be converted into light having a specific wavelength range (a specific color). In some embodiments, the encapsulation structure 25 or the wavelength conversion layer 44 may include a matrix (base material) and particles dispersed in the matrix. In some embodiments, the material of the matrix may comprise an organic polymer, an inorganic polymer, glass, or a combination of the foregoing, but is not limited thereto. In some embodiments, the substrate may be transparent or translucent.

In some embodiments, the particles may include phosphor(s), Quantum Dot (QD) materials, organic fluorescent materials, other suitable materials, or combinations of the foregoing materials, but are not limited thereto. In some embodiments, the package structure 25 or the wavelength conversion layer 44 may include a phosphor for converting the light source to red, green, blue, or other suitable color of light. In some embodiments, the quantum dot material may have a core-shell (core-shell) structure. The core structure may include cadmium selenide (CdSe), cadmium telluride (CdTe), cadmium sulfide (CdS), zinc sulfide (ZnS), zinc selenide (ZnSe), zinc oxide (ZnO), zinc telluride (ZnTe), indium arsenide (InAs), indium phosphide (InP), gallium phosphide (GaP), other suitable materials, or combinations of the foregoing, but is not limited thereto. The shell structure may include, but is not limited to, zinc sulfide (ZnS), zinc selenide (ZnSe), gallium nitride (GaN), gallium phosphide (GaP), other suitable materials, or combinations thereof.

Furthermore, in some embodiments, the encapsulation structure 25 or the wavelength conversion layer 44 may include scattering particles (scatterers). For example, the scattering particles may be of a material with high reflectivity (e.g., greater than 30%). The scattering particles can further improve the light absorption efficiency of the quantum dot material or change the distribution of light intensity under different viewing angles. In some embodiments, the material of the scattering particles may comprise titanium (Ti) or zinc (Zn). For example, in some embodiments, the scattering particles may comprise titanium dioxide (TiO)₂) Niobium-doped titanium oxide (TNO), zinc oxide (ZnO), zirconium dioxide (ZrO)₂) Or a combination of the foregoing, but the application is not limited thereto.

In some embodiments, the package structure 25 or the wavelength conversion layer 44 may be formed by a chemical vapor deposition process, a coating process, a printing process, an inkjet printing process, a die forming process, or other suitable methods or combinations thereof. Alternatively, the package structure 25 or the wavelength conversion layer 44 may be formed by one or more photolithography processes and etching processes.

Fig. 4 is a schematic diagram of some embodiments of the present application, and fig. 5A to 5D and fig. 6A to 6B are top views of some embodiments of the present application with different optical layers, wherein the optical layer 30 can be replaced with the optical layers in fig. 5A to 5D or fig. 6A to 6B, depending on the design requirements.

First, in fig. 4, 5A and 5B, the optical layer 30A (equal to the optical layer 30 in fig. 4) may include a first region R1 and a second region R2. As shown in fig. 4, 5A and 5B, the first region R1 may be a region overlapping with the light emitting chip group 26 or the light emitting chip 27 in a top view direction, and the second region R2 may be a region not overlapping with the light emitting chip group 26 (or the light emitting chip 27) in a top view direction. In other words, the first region R1 is a union of the orthographic projections of the individual light emitting chips in the light emitting chip set 26 or the orthographic projection of the light emitting chip 27. In the case of the light emitting chip group 26 having the plurality of

light emitting chips

26A, 26B, and 26C as in fig. 5B, the area of the first region R1 is the sum of the areas of the

light emitting chips

26A, 26B, and 26C.

In some embodiments, the optical layer 30A may include an optical material 31A and a plurality of

holes

32A, 32B, 32C in the optical material 31A. The optical material 31A may be, for example, a material with high reflectivity, such as a metal or other composite materials with different refractive indexes, etc., but the application is not limited thereto. In some embodiments, the metal may include silver, aluminum, gold, nickel, or combinations thereof, and the composite material may include TiO₂、SiO₂、Nb₂O₅、Ta₂O₅、ZrO₂、Al₂O₃、Y₂O₃MgO, combinations of the above materials, and the like, but the present application is not limited thereto.

In some embodiments, as shown in fig. 5A and 5B, the hole 32C may be located in the first region R1, and the

holes

32A and 32B may be located in the second region R2 when viewed from the top. More specifically, when viewed from the top, the hole 32C overlaps the light emitting chip set 26 (or the light emitting chip 27), the hole 32A and the hole 32B are spaced from the light emitting chip set 26 (or the light emitting chip 27), and the distance between the hole 32B and the light emitting chip set 26 (or the light emitting chip 27) (i.e., the shortest distance between the edge of the projection of the hole 32B and the edge of the projection of the light emitting chip set 26 or the light emitting chip 27 in the top view) is smaller than the distance between the hole 32A and the light emitting chip set 26 (or the light emitting chip 27). In addition, the area density of the holes 32A in the first region R1 is less than the area density of the

holes

32B, 32C in the second region R2.

It should be noted that "area density" herein refers to a proportion of a total area of projections of holes (or slits, light blocking patterns, and the like mentioned later) in a planar view direction in the optical layer per unit area, and areas of the first region R1 and the second region R2 are an area where the optical layer overlaps with the light-emitting chip group 26 (or the light-emitting chip 27) in the planar view direction and an area where the optical layer does not overlap with the light-emitting chip group 26 (or the light-emitting chip 27), respectively. It should be noted that in some embodiments (such as the embodiment shown in fig. 10C), the optical layers may be continuously disposed, and the area measurement range of the second region R2 may be limited to a square range with a side length of several millimeters (mm) instead of measuring the whole optical layer. In addition, in some embodiments, the light emitting chips in the light emitting chip set 26 may be distributed, and in this case, the first region R1 may be regarded as a portion overlapping each light emitting chip in the top view direction, and the area of the first region R1 is the sum of the areas of the portions overlapping each light emitting chip.

Thereby, the transmittance of the optical layer 30A may be increased from the center to the edge, i.e., the transmittance of the first region R1 may be less than that of the second region R2. Therefore, the light emitted from the light emitting chip set 26 (or the light emitting chip 27) to the first region R1 tends to be reflected rather than transmitted, which can produce the light emitting effect as shown in fig. 2B, so as to improve the problem that the light intensity declines too fast with the increase of the viewing angle. Note that in this application, the transmittance is a ratio of the intensity of the outgoing light to the intensity of the incoming light (that is, transmittance is outgoing light intensity/incoming light intensity).

In some embodiments, the size (e.g., maximum width) of the aperture 32A may be greater than the size of the aperture 32B, and the size of the aperture 32B may be greater than the size of the aperture 32C, such that the aperture area density of the first region R1 is less than the aperture area density of the second region R2. However, the present application is not limited thereto. For example, the

holes

32A, 32B, 32C may have the same size, and the hole area density may be changed by changing the number of holes per unit area, i.e. the number of holes in the second region is larger than the number of holes in the first region, and the invention is not limited thereto.

In some embodiments, in addition to providing holes in the optical layer, slits having different area densities may also be provided to achieve the aforementioned effects. For example, fig. 5C and 5D are top views of light emitting devices according to some embodiments of the present disclosure, in which the optical layer 30B has

rectangular slits

34A, 34B, and 34C, and the optical layer 30C of fig. 5D has

circular slits

36A, 36B, and 36C (for example, but not limited to, concentric circles). It should be noted that, in the embodiment, the slit 34A or the slit 36A is located in the first region R1, and the

slits

34B, 34C or the

slits

36B, 36C are located in the second region R2, the distance between the slit 34B and the first region R1 (i.e., the shortest distance between the projection of the slit 34B and the edge of the projection of the light emitting chip set 26 or the light emitting chip 27 in the top view direction, and the distance between the other slits is measured in the same manner) is smaller than the distance between the slit 34C and the first region R1, the distance between the slit 36B and the first region R1 is smaller than the distance between the slit 36C and the first region R1, and the widths of the

slits

34A, 34B, 34C (or the

slits

36A, 36B, 36C) may increase with increasing distance from the center of the optical layer 30C (or the optical layer 30D). Thereby, the area density of the slits in the first region R1 can be made smaller than the area density of the slits in the second region R2. Therefore, the transmittance of the

optical layer

30B or 30C increases from the center to the edge, i.e., the transmittance of the first region R1 is smaller than that of the second region R2, so that the problem of the light intensity declining too fast with the increase of the viewing angle can be improved.

In the foregoing embodiments, the optical material 31A with high reflectivity is matched with the holes or slits to achieve the improvement of the light intensity at different viewing angles, but the present application is not limited thereto. For example, in some embodiments, as shown in fig. 6A and 6B, an optical material 31B with a high transmittance (e.g., a transmittance higher than that of the optical material 31A) may also be used in the optical layer 30D, and a plurality of

light blocking patterns

38A, 38B, 38C may be disposed in the optical material 31B. The

light blocking patterns

38A, 38B, 38C may include a reflective material similar to the aforementioned optical material 31A, but is not limited thereto. In some embodiments, the

light blocking patterns

38A, 38B, 38C may also be made of a material having light absorbing properties.

The light-blocking pattern 38C may be disposed in the first region R1, and the light-blocking

patterns

38A, 38B may be disposed in the second region R2. In some embodiments, the size (e.g., the maximum width) of the light-blocking pattern 38A may be smaller than the size of the light-blocking pattern 38B, and the size of the light-blocking pattern 38B may be smaller than the size of the light-blocking pattern 38C, so that the light-blocking pattern area density of the first region R1 is greater than the light-blocking pattern area density of the second region R2. Therefore, the transmittance of the optical layer 30A can be increased from the center to the edge, that is, the transmittance of the first region R1 is smaller than that of the second region R2, so as to improve the problem that the light intensity declines too fast with the increase of the viewing angle.

Although the foregoing embodiments describe three

holes

32A, 32B, 32C, slits 34A, 34B, 34C, slits 36A, 36B, 36C, and

light blocking patterns

38A, 38B, 38C with different sizes, they are only illustrative and the present application is not limited thereto. For example, the holes, slits, or light blocking patterns may have the same size or more than three different sizes, depending on the design requirements.

In addition, the reflectivity of the optical layer at different positions can be changed by making the optical layer have different thicknesses at different areas. For example, in fig. 7, the optical layer 30E may have a multi-layer structure, and the thickness T1 of the optical layer 30E in the first region R1 is greater than the thickness T2 of the optical layer 30E in the second region R2 (e.g., there are more optical layers in the first region R1). Alternatively, the optical layer may be designed as a single optical layer having a thickness greater at the center than at the edges, so that the transmittance of the first region R1 is less than that of the second region R2, thereby improving the problem that the light intensity declines too fast with the increase of the viewing angle. The thicknesses of the optical layers in the first region R1 and the second region R2 are the maximum thicknesses in the plan view direction from the top surface of the optical layer 30E to the top surface of the light-emitting unit 20 in the individual regions.

Fig. 8 is a schematic diagram of the reflectivity of the optical layer at different positions according to some embodiments of the present application (such as the embodiments of fig. 4 to 7), where the X-axis represents the position (as indicated by the line a-a' in fig. 4, the origin is the center of the light emitting chip set 26 or the light emitting chip 27), and the Y-axis represents the reflectivity of the optical layer. It should be noted that the reflectance of the optical layer is larger as it is closer to the center of the light emitting chip group 26 or the light emitting chip 27 on the X-axis. Thereby, light in a small angle direction (approaching a top view direction of the substrate in the light emitting device) is more easily reflected by the optical layer, and instead, light is emitted from a larger angle.

In some embodiments, as shown in fig. 9A and 9B, the light emitting unit 20 and the optical layer 30 may be disposed on the transparent substrate 12, and a reflective layer 50 may be additionally provided on the substrate 12. The substrate 12 may comprise a transparent material such as glass, polyimide, or other suitable material, or a combination of the foregoing, but is not limited thereto. In addition, a Thin Film Transistor (TFT) or a driving circuit (not shown) may be further included on the substrate 12, wherein the driving circuit may be, for example, an Active (Active) driving circuit or a Passive (Passive) driving circuit. According to some embodiments, the driving circuit may include a transistor (e.g., a switching transistor or a driving transistor, etc.), a data line, a scan line, a conductive pad, a dielectric layer, or other lines, etc., but is not limited thereto.

The reflective layer 50 may be formed of a material having a reflective property. In some embodiments, the material of the reflective layer 50 may comprise a metal. For example, the metal material may include copper (Cu), aluminum (Al), indium (In), ruthenium (Ru), tin (Sn), gold (Au), platinum (Pt), zinc (Zn), silver (Ag), titanium (Ti), lead (Pb), nickel (Ni), chromium (Cr), magnesium (Mg), palladium (Pd), an alloy of the foregoing metal materials, other suitable materials, or a combination of the foregoing materials, but is not limited thereto. In other embodiments, the material of the reflective layer 50 may further include titanium dioxide, silicon dioxide, other suitable materials, or a combination thereof, but is not limited thereto. In some embodiments, the reflective layer 50 may be disposed on the same side of the substrate 12 as the light emitting unit 20 (as shown in fig. 9A) or the reflective layer 50 and the light emitting unit 20 may be disposed on different sides of the substrate 12 (as shown in fig. 9B), respectively, without limitation. Thereby, the light emitted onto the substrate 12 can be reflected to the direction having the display layer (e.g., the display layer 42 of fig. 3A) to improve the brightness of the light-emitting device.

In some embodiments, the reflective layer 50 may be formed by the deposition process, the coating process, the printing process, the inkjet printing process, other suitable methods, or a combination thereof. Alternatively, the reflective layer 50 may be formed by one or more photolithography processes and etching processes.

In the foregoing embodiment, the package substrate 22 is disposed between the light emitting chip set 26 and the substrate 10, but the present application is not limited thereto. Fig. 10A to 10E are schematic views of some elements of a light emitting device according to some embodiments of the present application. In fig. 10A, the light emitting chip set 26 of the light emitting device 4A may be disposed on the substrate 10 and does not include the package substrate 22. A driving circuit (not shown) for driving the light emitting chip set 26 may be disposed on the surface of the substrate 10. Thereby, the process required for manufacturing the light emitting device 4A can be simplified.

In addition, a combination of the transparent substrate 12 and the reflective layer 50 may be used instead of the substrate 10. For example, in fig. 10B to 10E, the

light emitting devices

4B, 4C, 4D, 4E have the transparent substrate 12 and the reflective layer 50, wherein the reflective layer 50 of the

light emitting devices

4B, 4C and the light emitting chip set 26 are disposed on different sides of the substrate 12, and the reflective layer 50 of the

light emitting devices

4D, 4E and the light emitting chip set 26 are disposed on the same side of the substrate 12. Furthermore, in some embodiments, the optical layer 30 may cover over the light emitting chip set 26 and expose a portion of the upper surface of the package structure 24 (as shown in fig. 10B), or the optical layer 30 may cover the entire upper surface of the package structure 24 (as shown in fig. 10C), depending on design requirements.

It should be noted that in the foregoing embodiments, a plurality of light emitting chip sets 26 may be disposed in the same package structure 24 (e.g., packaged in the same package structure 24). Therefore, the required manufacturing process can be simplified. However, the present application is not limited thereto. For example, in fig. 10E, the light emitting chip sets 26 on the light emitting device 4E are disposed in different package structures 24.

In some embodiments, as shown in the light emitting device 5 of fig. 11, a light guide layer 60 may be additionally disposed between the light emitting chip set 26 and the optical layer 30 to make the light emitted from the light emitting chip set 26 uniform. The material of the light guiding layer 60 can be, for example, plastic, glass, polyimide, sapphire, other suitable materials, or a combination thereof, but is not limited thereto. Furthermore, in some embodiments, the top surface of light emitting chipset 26 (the surface away from substrate 12) may directly contact light guiding layer 60, or there may be a portion of package structure 24 between light emitting chipset 26 and light guiding layer 60, which is not limited herein.

In some embodiments, an additional anti-reflection layer may be added on the substrate of the light emitting device to reduce the influence of external light reflected by the substrate onto the light emitting chip. For example, as shown in fig. 12, the substrate 10 of the light-emitting device 6 has an anti-reflection layer 70 thereon. The material of the anti-reflective layer 70 may include, but is not limited to, a material with low light reflectivity, such as a black photoresist or an absorbing glue. Therefore, the influence of the light reflected by the substrate 10 on the adjacent light emitting devices can be reduced to increase the service life of the light emitting devices, or reduce the mutual interference between the light emitting devices, or reduce the overall image quality due to the reflection of the ambient light source such as sunlight when the light emitting device 6 is used as a display device in an outdoor environment. When the light-emitting device 6 is used as a display device, the light-emitting device of the light-emitting device 6 can directly display an image as a pixel, for example.

In some embodiments, anti-reflective layer 70 may be formed by the deposition process, coating process, printing process, inkjet printing process, other suitable methods, or combinations thereof. Furthermore, the anti-reflective layer 70 may be formed by one or more photolithography processes and etching processes.

In summary, some embodiments of the present application provide light emitting devices having an optical layer on a light emitting unit. By using the optical layers with different penetration rates in different areas in the light-emitting device, the problem that the light-emitting intensity of the light-emitting device declines too fast along with the increase of the visual angle can be solved, so that the using effect of the light-emitting device using the light-emitting device is improved. In addition, features of the various embodiments may be combined and matched as desired, without departing from the spirit or ambit of the invention.

The light-emitting device manufactured in the foregoing embodiment of the present application can also integrate a touch function as a touch electronic device. In addition, the light emitting device or the touch electronic device manufactured in the foregoing embodiments of the present application can be applied to any electronic device that requires a display screen, such as a display, a mobile phone, a watch, a notebook computer, a video camera, a mobile navigation device, a television, and the like. The touch electronic device manufactured in the foregoing embodiments of the present application can also be applied to an electronic device with an antenna function or other types of electronic devices.

Although the embodiments of the present application and their advantages have been disclosed above, it should be understood that they may be combined, changed, substituted, and modified by those skilled in the art without departing from the spirit and scope of the present application. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification, but it is to be understood that any process, machine, manufacture, composition of matter, means, methods and steps, presently existing or later to be developed, that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present application. Accordingly, the scope of the present application includes the processes, machines, manufacture, compositions of matter, means, methods, and steps described above. In addition, each claim constitutes a separate embodiment, and the scope of protection of the present application also includes combinations of the respective claims and embodiments.

Claims

1. A light emitting device comprising:

the light-emitting unit comprises a light-emitting chip and a packaging structure arranged on the light-emitting chip; and

the optical layer is arranged on the light-emitting unit and provided with a first area which is overlapped with the light-emitting chip in a top view direction of the light-emitting device and a second area which is not overlapped with the light-emitting chip in the top view direction of the light-emitting device, and the penetration rate of the first area is smaller than that of the second area.

2. The light-emitting device according to claim 1, wherein the optical layer comprises a plurality of holes, and an area density of the plurality of holes in the first region is less than an area density of the plurality of holes in the second region.

3. The light-emitting device according to claim 1, wherein the optical layer includes a plurality of light-blocking patterns, and an area density of the light-blocking patterns in the first region is greater than an area density of the light-blocking patterns in the second region.

4. The light-emitting device according to claim 1, wherein a thickness of the first region is greater than a thickness of the second region.

5. The light-emitting device according to claim 1, wherein the optical layer comprises a metallic material.

6. The light-emitting device according to claim 5, wherein the metal material comprises silver, aluminum, gold, nickel, and combinations thereof.

7. The light-emitting device according to claim 1, wherein the optical layer comprises a composite material, and the composite material comprises TiO₂、SiO₂、Nb₂O₅、Ta₂O₅、ZrO₂、Al₂O₃、Y₂O₃MgO, and combinations thereof.

8. The light-emitting device according to claim 1, wherein the optical layer is a bragg mirror.

9. The light-emitting device according to claim 1, wherein the light-emitting unit further includes another light-emitting chip.

10. The light-emitting device according to claim 9, wherein the other light-emitting chip is different in color from the light emitted from the light-emitting chip.