Improved light emitting device

Abstract

This invention provides an apparatus. The apparatus includes a stacked blue light emitting device, comprising: a first electrode; a second electrode; a first emitting unit including a first emitting layer; a second emitting unit including a second emitting layer; and a first charge generating layer; wherein the first emitting unit, the second emitting unit, and the first charge generating layer are all disposed between the first electrode and the second electrode; the first emitting unit is disposed above the first electrode; the first charge generating layer is disposed above the first emitting unit; the second emitting unit is disposed above the first charge generating layer; and the second electrode is disposed above the second emitting unit; the first emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm, the peak wavelength being defined as a first peak wavelength; the first emitting unit emits blue light with chromaticity coordinates (x1, y1) in a first CIE 1931 (x, y) color space; the second emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm, the peak wavelength being defined as a second peak wavelength; and the second emitting unit emits blue light having a second chromaticity, the second chromaticity being defined as a second CIE 1931 (x, y) color space. The chromaticity coordinates of the 1931(x,y) color space are (x2,y2); the second chromaticity is substantially different from the first chromaticity; and the first and second emission layers include organic light-emitting materials, quantum dot light-emitting materials and / or perovskite light-emitting materials.

Description

Technical Field

[0001] The present invention relates to a novel light-emitting device architecture for use in displays, lighting panels and other optoelectronic devices, and more particularly to a stacked blue light emitting device comprising two or more emitting units that emit blue light having substantially different chromaticities. Background Technology

[0002] Organic light-emitting diode (OLED) technology is rapidly evolving, with recent innovations enabling thinner and lighter displays with higher resolution, improved frame rates, and enhanced contrast ratios. OLED technology is now considered the cutting edge for small-area displays and is widely used in flagship smartphones such as the Samsung Galaxy S20 Ultra, iPhone 11 Pro Max, and OnePlus 8 Pro, all of which incorporate efficient, bright, and colorful OLED displays.

[0003] Despite the continued success of OLED technology in the small-area display market, relatively few large-area displays (such as televisions) incorporate OLED technology. Most televisions are still manufactured using a modified liquid crystal display (LCD) architecture. This apparent difference can be explained by the differences in the display architecture between small-area OLED smartphone displays and large-area OLED television displays.

[0004] OLED smartphones include an RGB OLED display architecture in which red, green, and blue organic light-emitting materials are patterned into individual red, green, and blue sub-pixels that emit red, green, and blue light, respectively. An exemplary RGB OLED display architecture is described below. Figure 18 The arrangement 1800 is depicted as follows: A red subpixel arrangement 1805 includes a red emitting layer 1840. A green subpixel arrangement 1815 includes a green emitting layer 1850. A blue subpixel arrangement 1825 includes a blue emitting layer 1860. The red, green, and blue emitting layers are disposed between a first electrode 1820 and a second electrode 1830. All layers are disposed on a substrate 1810. An exemplary RGB OLED display architecture of arrangement 1800 may include... Figure 18Optional additional device layers not depicted. Patterning of the red, green, and blue emitting layers is achieved by depositing red, green, and blue organic light-emitting materials via vapor-phase thermal evaporation through a fine metal mask with openings precisely aligned with the corresponding red, green, and blue sub-pixels. The RGB OLED display architecture offers high performance because each of the red, green, and blue sub-pixels can be individually optimized to emit efficient, bright, and colorful light. The RGB OLED display architecture is also relatively low-cost because each of the red, green, and blue sub-pixels typically comprises a simple stack of approximately 6-7 evaporated layers in the OLED device.

[0005] Unfortunately, the RGB OLED display architecture, so successfully used in smartphones, has not yet been successfully extended to televisions. The problem is that manufacturing televisions requires much larger glass substrates (e.g., 3130mm × 2880mm Gen 10 substrates) compared to manufacturing smartphones (e.g., 1800mm × 1500mm Gen 6 substrates). The fine metal masks required to pattern the red, green, and blue organic light-emitting materials into red, green, and blue subpixels then tend to sag over the larger substrate area, resulting in misalignment and undesirable shading effects.

[0006] In contrast, OLED TVs include an RGBW OLED display architecture, where each subpixel of the display comprises a white OLED. Individual patterning of different subpixels is not required. An exemplary RGBW OLED display architecture is shown below. Figure 19 The arrangement is depicted as 1900. Red, green, and blue color filters are patterned on three-quarters of the white OLED sub-pixels. The red sub-pixel arrangement 1905 includes a white OLED optically coupled to a red color filter 1985. The green sub-pixel arrangement 1915 includes a white OLED optically coupled to a green color filter 1990. The blue sub-pixel arrangement 1925 includes a white OLED optically coupled to a blue color filter 1995. The white sub-pixel arrangement 1935 includes a white OLED without color filters. Each white OLED includes a stacked light-emitting device with three emitting units: a red emitting layer 1930, a green emitting layer 1950, and a blue emitting layer 1970, all disposed between a first electrode 1920 and a second electrode 1980. The red emitting layer 1930 is separated from the green emitting layer 1950 by a first charge-generating layer 1940. The green emitting layer 1950 is separated from the blue emitting layer 1970 by a second charge-generating layer 1960. All layers are disposed on substrate 1910. An exemplary RGBW OLED display architecture with 1900 arranged may include Figure 19 Optional additional device layers not depicted in the text.

[0007] Unfortunately, the RGBW OLED display architecture used in OLED TVs offers reduced performance compared to the RGB OLED display architecture used in OLED smartphones. This is because most of the light emitted from the white OLEDs in the red, green, and blue subpixels is filtered out. This reduces the display's efficiency and brightness. The color richness of RGBW OLED displays is also limited because there is a trade-off between using stronger color filters to expand the display's color gamut and reducing brightness by filtering out more white light. RGBW OLED display architectures are also relatively expensive because each of the red, green, and blue subpixels typically consists of a stack of approximately 15-20 white OLED devices with evaporated layers.

[0008] Therefore, compared to OLED smartphones with an RGB OLED display architecture, OLED TVs with an RGBW OLED display architecture are less efficient, have lower brightness, fewer colors, and are relatively more expensive. This is why OLED technology is widely used in smartphones rather than televisions. To address this challenge, Samsung recently proposed a new QD-OLED display architecture. An exemplary QD-OLED display architecture is shown below. Figure 20 The arrangement 2000 is depicted in the diagram. In this QD-OLED display architecture, each subpixel of the display comprises a blue OLED. Red and green color conversion layers are then patterned on two-thirds of the blue OLED subpixels. A red subpixel arrangement 2005 includes a blue emitting layer 2040 optically coupled to a red color conversion layer 2050. A green subpixel arrangement 2015 includes a blue emitting layer 2040 optically coupled to a green color conversion layer 2060. A blue subpixel arrangement 2025 includes a blue emitting layer 2040 without a color conversion layer. The blue emitting layer is disposed between a first electrode 2020 and a second electrode 2030. All layers are disposed on a substrate 2010. An exemplary QD-OLED display architecture of arrangement 2000 may include those without a color conversion layer. Figure 20 The optional additional device layer depicted in the text.

[0009] Samsung has stated that the red and green color conversion layers include quantum dot (QD) materials, which led to the name QD-OLED used in this display architecture.

[0010] The QD-OLED display architecture is expected to be an improvement over the RGBW OLED display architecture. This is because using a color conversion layer to convert blue light into red or green light is a more efficient process than using color filters to filter white light into red, green, or blue light. Therefore, QD-OLED displays are expected to be more efficient, brighter, and more colorful than RGBW OLED displays. Furthermore, the blue OLED device stacking in QD-OLED displays is simpler and can include fewer layers compared to the white OLED stacking in RGBW OLED displays. This reduces costs. These improvements can all be achieved without fine metal mask technology, because for RGBW OLED displays, QD-OLED displays can be manufactured without individually patterning the light-emitting materials of different sub-pixels.

[0011] However, the proposed QD-OLED display architecture does have drawbacks. Specifically, a significant drawback is that the lifetime of blue OLED devices is typically shorter than that of red and green OLED devices, and in the QD-OLED display architecture, the blue OLED is used to provide light for both red and green subpixels, as well as the blue subpixels. This is expected to limit the lifetime of the QD-OLED display. Furthermore, the blue light emitted by the blue OLED must be highly saturated to enable the display to render deep blues and an extended color gamut. The problem is that deep blue phosphor emitters with higher efficiency are relatively unstable and unsuitable for commercial applications. Therefore, it is anticipated that a deep blue phosphor emitter with lower efficiency but relatively improved stability will be required. This will reduce the efficiency and brightness of the QD-OLED display. Additionally, the blue light emitted by the blue OLED must be optimized to match the absorption of both red and green color conversion materials and be deep enough to enable the display to render deep blues for extended color gamuts. There may be trade-offs that will lead to performance degradation.

[0012] This invention addresses these problems by proposing a stacked blue light emitting device architecture comprising two or more emitting units that emit blue light with substantially different chromaticities for use in displays, lighting panels, and other optoelectronic devices. Optionally, at least one emitting unit may emit a deeper blue light, and at least one emitting unit may emit a lighter blue light.

[0013] The proposed architecture is passed Figure 21An exemplary arrangement 2100 for a stacked blue light emitting device having two emitting units is depicted. A red sub-pixel arrangement 2105 includes a first blue emitting unit 2130 and a second blue emitting unit 2150, which are separated by a first charge generation layer 2140 and optically coupled to a red color conversion layer 2170. A green sub-pixel arrangement 2115 includes a first blue emitting unit 2130 and a second blue emitting unit 2150, which are separated by a first charge generation layer 2140 and optically coupled to a green color conversion layer 2180. A blue sub-pixel arrangement 2125 includes a first blue emitting unit 2130 and a second blue emitting unit 2150, which are separated by a first charge generation layer 2140. The layers of the first and second blue emitting units, as well as the first charge generation layer, are disposed between a first electrode 2120 and a second electrode 2160. All layers are disposed on a substrate 2110. At least one of the first blue emitting unit 2130 and the second blue emitting unit 2150 can emit a lighter blue light, and at least one of the first blue emitting unit 2130 and the second blue emitting unit 2150 can emit a darker blue light.

[0014] Optionally, the stacked blue light emitting device architecture of the present invention may include a third emitting unit 2220 and a second charge generating layer 2210. This is achieved through... Figure 22 An exemplary arrangement 2200 for a stacked blue light emitting device having three emitting units is depicted. The third emitting unit 2220 may emit either a lighter or darker blue light.

[0015] Optionally, the transmitting units can be addressed independently and can emit light independently of each other. Optionally, the transmitting units can be jointly addressed and can emit light without being independent of each other.

[0016] Such stacked blue light emitting devices can be incorporated into the red, green, and blue subpixels of an OLED display. When the blue subpixels of such a display are required to emit relatively saturated blue light (more saturated than light emitted from lighter blue emitting units, but less saturated than light emitted from darker blue emitting units), the emitting units emitting darker blue light can be addressed individually and emit light to generate the display image, while the emitting units emitting lighter blue light remain inactive. However, when only the blue subpixels of such a display are required to emit relatively unsaturated blue light (less saturated than light emitted from lighter blue emitting units), the emitting units emitting lighter blue light can be addressed individually and emit light to generate the display image, while the emitting units emitting darker blue light remain inactive. Light can be emitted from the relatively more efficient and / or more stable lighter blue emitting units to render most of the display image, while light emitted from the relatively less efficient and / or less stable darker blue emitting units only needs to render a small portion of the image. This improves the efficiency and / or lifespan of the display. In addition, lighter blue emitting units can be used alone or in combination with darker blue emitting units to provide light to the red and green color conversion layers in the red and green subpixels.

[0017] Optionally, the lighter blue emitting unit may include a phosphorescent organic light-emitting material or a fluorescent organic light-emitting material. Optionally, the darker blue emitting unit may include a phosphorescent organic light-emitting material or a fluorescent organic light-emitting material. Optionally, the lighter blue emitting unit may include a fluorescent organic light-emitting material, and the darker blue emitting unit may include a fluorescent organic light-emitting material. Optionally, the lighter blue emitting unit may include a phosphorescent organic light-emitting material, and the darker blue emitting unit may include a fluorescent organic light-emitting material.

[0018] The proposed novel device architecture is ideally suited for OLED devices and displays. It is also ideally suited for quantum dot light-emitting diode (QLED) displays incorporating quantum dot luminescent materials and perovskite light-emitting diode (PeLED) displays incorporating perovskite luminescent materials. The inherent properties of organic light-emitting materials, quantum dot luminescent materials, and perovskite luminescent materials make them highly suitable for the stacked blue light-emitting device architecture disclosed herein. These properties include easily tunable optical band gaps in the visible, ultraviolet, and infrared spectra, high color saturation with a wide color gamut, excellent charge transport characteristics, and low emissivity.

[0019] The proposed novel device architecture has several advantages over related technologies, as demonstrated by the following exemplary related technologies:

[0020] WO 2019 / 224546 A1 discloses a stacked light-emitting device comprising at least one PeLED emitting unit and at least one PeLED, OLED, or QLED emitting unit. The emitting units can be of any color and can be co-addressable or independently addressable. The emitting units can be optically coupled to one or more color conversion layers. This has the advantage of allowing different classes of emitting materials (such as OLED, QLED, and PeLED) to be combined in the stacked light-emitting device. However, unlike this disclosure, WO 2019 / 224546 A1 does not disclose details of how such a stacked light-emitting device architecture can be implemented in one or more sub-pixels of a display. Furthermore, it does not disclose any implementation in which the emitting units may have different chromaticities, nor does it describe any application or advantage of emitting units with different chromaticities. It only discloses chromaticity data for exemplary emitting units including different classes of emitting materials. Unlike this disclosure, WO 2019 / 224546 A1 is also limited to stacked light-emitting devices in which one or more PeLED emitting units are combined with one or more PeLED, OLED, or QLED emitting units. It does not include stacked light-emitting devices that only include OLED emission units, only include QLED emission units, or only include PeLED emission units, which would be easier to manufacture.

[0021] US 2019 / 0043407 A1 discloses a pixel layout for a display that includes a blue subpixel comprising a stacked blue light emitting device having two independently addressable blue emitting units with different chromaticities, and (as disclosed in paragraphs

[0043] and

[0057] ) includes red and green subpixels that are single-junction (non-stacked) light-emitting devices. Unlike this disclosure, the pixel layout disclosed in US 2019 / 0043407 A1 does not include red and green color conversion layers and requires that the red, green, and blue emitting units be patterned separately into their respective subpixels. This can increase the complexity and cost of the manufacturing process and may be difficult to scale to substrates with larger areas.

[0022] EP 3188272 A1 discloses a stacked blue light emitting device comprising a first emitting unit and a second emitting unit separated by a charge-generating layer. The first emitting unit includes a first emitting layer that emits blue light, and the second emitting unit includes a second emitting layer that emits blue light, wherein the first and second emitting layers emit light of different chromaticities. An example with three emitting units, each comprising a separate emitting layer, is also disclosed. A display architecture is also included, wherein color conversion material is present on red and green subpixels. Unlike this disclosure, in EP 3188272 A1... Figure 7 and Figure 8 The emission units disclosed in the previous method are jointly addressable, and the charge generation layer is shared by all sub-pixels. No emission units that can be independently addressed are disclosed. Therefore, unlike this disclosure, it is not possible to select and independently address different emission units and different emission layers of different chromaticities to render an image based on the image content. Therefore, it is not possible to achieve an equivalent reduction in power consumption and an increase in device lifespan.

[0023] WO 2020 / 030042 A1 discloses an OLED display comprising at least a first blue emitting layer and one or more additional blue emitting layers disposed over the entire display area of ​​a substrate, and a quantum dot color film disposed on the light-emitting side of the substrate. Paragraphs

[0065] and

[0066] describe the blue emitting layers emitting blue light of different chromaticities, one emitting layer emitting at 400 nm–440 nm and another emitting layer emitting at 440 nm–490 nm. The quantum dot film may include red quantum dots for red subpixels and green quantum dots for green subpixels. Blue subpixels may or may not include quantum dots. The blue emitting layers may be connected in series by charge-generating layers, as in a standard stacked device, or separate anode and cathode may exist for each electrically connected emitting unit. Unlike this disclosure, the emitting layers disclosed in WO 2020 / 030042 A1 are described as being connected in series. No independently addressable emitting units are disclosed. Therefore, unlike this disclosure, it is not possible to select and independently address different emission units and different emission layers with different chromaticities based on the image content to render the image. Consequently, it is not possible to achieve an equivalent reduction in power consumption and an increase in device lifespan.

[0024] As an overview, several OLED materials and configurations are described in Uoyama et al., as well as European Patent EP 0423283 B1 and US Patents US 6303238 B1 and US 7279704 B2. Several QLED materials and configurations are described in Kathirgamanathan et al. Several PeLED materials and configurations are described in Adjokatse et al. All of these references are incorporated herein by reference in their entirety.

[0025] As used herein, the term "organic" encompasses both polymeric materials and small-molecule organic materials that can be used to manufacture optoelectronic devices such as OLEDs. As used herein, the term "small molecule" refers to any organic material that is not a polymer, and small molecules can actually be quite large. In some cases, small molecules can contain repeating units. For example, using long-chain alkyl groups as substituents does not remove the molecule from the small-molecule level. Small molecules can also be incorporated into polymers, for example, as side groups on the polymer backbone or as part of the backbone. Dendritic structures can be small molecules, and it is believed that all dendritic structures currently used in the OLED field are small molecules.

[0026] As used herein, the term "organic light-emitting material" includes fluorescent and phosphorescent organic light-emitting materials, as well as organic materials that emit light through mechanisms such as triplet-triplet annihilation (TTA) or thermally activated delayed fluorescence (TADF) or strong fluorescence. As used herein, organic materials that emit light through mechanisms such as TADF or strong fluorescence are considered fluorescent organic light-emitting materials. An example of an organic light-emitting material that emits red light is bis(2-(3,5-dimethylphenyl)quinoline-C2,N')(acetylacetone)iridium(III)Ir(dmpq)2(acac). An example of an organic light-emitting material that emits green light is tris(2-phenylpyridine)iridium(Ir(ppy)3). An example of an organic light-emitting material that emits blue light is bis[2-(4,6-difluorophenyl)pyridine-C2,N](pyridinecarboxyl)iridium(III)(FIrpic).

[0027] Typically, OLED devices can be photoluminescent or electroluminescent. The term "OLED" can be used to describe an electroluminescent device comprising a single emitting unit of electroluminescent organic light-emitting material. The term "OLED" can also be used to describe one or more emitting units of a stacked electroluminescent device comprising electroluminescent organic light-emitting material. This terminology may differ slightly from that used in other sources.

[0028] As used herein, the term "quantum dot" encompasses quantum dot materials, quantum rod materials, and other luminescent nanocrystal materials, except for "perovskite" materials as defined separately herein. Quantum dots can generally be considered as semiconductor nanoparticles exhibiting properties intermediate between bulk semiconductors and discrete molecules. Quantum dots can include: III-V semiconductor materials such as gallium nitride (GaN), gallium phosphide (GaP), gallium arsenide (GaAs), indium phosphide (InP), and indium arsenide (InAs); or II-VI semiconductor materials such as zinc oxide (ZnO), zinc sulfide (ZnS), cadmium sulfide (CdS), cadmium selenide (CdSe), and cadmium telluride (CdTe), or combinations thereof. Typically, due to quantum confinement effects, the optoelectronic properties of quantum dots may vary with the size or shape of the quantum dot.

[0029] Several types of quantum dots can be stimulated to emit light in response to optical or electro-excitation. That is, quantum dot luminescent materials can be photoluminescent or electroluminescent. This terminology may differ slightly from that used in other sources.

[0030] As used herein, the term "quantum dot" does not include "perovskite" materials. Several types of perovskite materials, such as perovskite nanocrystals, 2D perovskite materials, and quasi-2D perovskite materials, are semiconductive materials exhibiting properties intermediate between bulk semiconductors and discrete molecules, where quantum confinement can influence optoelectronic properties in a manner similar to quantum dots. However, as used herein, such materials are referred to as "perovskite" materials rather than "quantum dot" materials. The first reason for this terminology is that perovskite materials and quantum dot materials, as defined herein, typically encompass different crystal structures. The second reason is that perovskite materials and quantum dot materials, as defined herein, typically include different material types within their structures. The third reason is that the emission of perovskite materials is generally independent of the perovskite material's structural size, while the emission of quantum dot materials typically depends on the quantum dot material's structural size (e.g., core and shell). This terminology may differ slightly from that used in other sources.

[0031] Typically, quantum dot luminescent materials consist of a core. Optionally, the core may be surrounded by one or more shells. Optionally, the core and one or more shells may be surrounded by a passivation structure. Optionally, the passivation structure may include ligands bound to one or more shells. The size of the core and one or more shells can affect the photoelectronic properties of the quantum dot luminescent material. Generally, as the size of the core and one or more shells decreases, the quantum confinement effect becomes stronger, and electroluminescence emission can be excited at shorter wavelengths. For display applications, the diameter of the core and shell structure is typically in the range of 1 nm to 10 nm. Quantum dots emitting blue light are typically the smallest, with core-shell diameters in the range of approximately 1 nm to 2.5 nm. Quantum dots emitting green light are typically slightly larger, with core-shell diameters in the range of approximately 2.5 nm to 4 nm. Quantum dots emitting red light are typically even larger, with core-shell diameters in the range of approximately 5 nm to 7 nm. It should be understood that these ranges are provided by way of example and are used to aid understanding, and are not intended to be limiting.

[0032] Examples of quantum dot luminescent materials include materials comprising a CdSe core. CdSe has a bulk bandgap of 1.73 eV corresponding to emission at 716 nm. However, by customizing the size of the CdSe quantum dots, the emission spectrum of CdSe can be tuned across the visible spectrum. Quantum dot luminescent materials comprising a CdSe core may further include one or more shells comprising CdS, ZnS, or combinations thereof. Quantum dot luminescent materials comprising CdSe may further include a passivation structure, which may contain ligands bound to one or more shells. Quantum dot luminescent materials comprising CdSe / CdS or CdSe / ZnS core-shell structures can be tuned to emit red, green, or blue light for applications in displays and / or lighting panels.

[0033] Examples of quantum dot luminescent materials further include materials comprising an InP core. InP has a bulk bandgap of 1.35 eV corresponding to emission at 918 nm. However, by customizing the size of the InP quantum dots, the emission spectrum of InP can be tuned across the visible spectrum. Quantum dot luminescent materials comprising an InP core may also include one or more shells of CdS, ZnS, or combinations thereof. Quantum dot luminescent materials comprising InP may further include a passivation structure that may contain ligands bound to one or more shells. Quantum dot luminescent materials comprising InP / CdS or InP / ZnS core-shell structures can be tuned to emit red, green, or blue light for applications in displays and / or lighting panels.

[0034] Typically, QLED devices can be either photoluminescent or electroluminescent. The term "QLED" can be used to describe a single-emitting electroluminescent device comprising electroluminescent quantum dot luminescent material. The term "QLED" can also be used to describe one or more emitting units in a stacked electroluminescent device comprising electroluminescent quantum dot luminescent material. This terminology may differ slightly from that used in other sources.

[0035] As used herein, the term "perovskite" encompasses any perovskite material that can be used in optoelectronic devices. Any material that can adopt a three-dimensional (3D) structure of ABX3 can be considered a perovskite material, where A and B are cations and X is an anion. Figure 3 Examples of perovskite materials with a 3D structure of ABX3 are described. The A cation can be larger than the B cation. The coordination ratio of the B cation to the surrounding X anion can be 6:1. The coordination ratio of the A anion to the surrounding X anion can be 12:1.

[0036] Perovskite materials are becoming increasingly attractive for applications in optoelectronic devices. Many perovskite materials used to fabricate such devices are abundant and relatively inexpensive on Earth, thus perovskite optoelectronic devices have the potential for cost advantages. Many grades of perovskite materials exist. One grade of perovskite material that has shown particular promise for optoelectronic devices is metal halide perovskite. For metal halide perovskite materials, component A can be a monovalent organic cation (such as methylamine hydrochloride (CH3NH3)). + ) or formamidin acetate (CH(NH2)2 + Inorganic atomic cations (such as cesium (Cs)) + Component B can be a divalent metal cation, such as lead (Pb) or a combination thereof. + ), Tin (Sn) + ), copper (Cu) + Europium (Eu) + ) or combinations thereof, and component X can be a halide anion, such as I - ,Br - Cl - Or combinations thereof. When component A is an organic cation, the perovskite material can be defined as an organometal halide perovskite material. CH3NH3PbBr3 and CH(NH2)2PbI3 are non-limiting examples of metal halide perovskite materials with a 3D structure. When component A is an inorganic cation, the perovskite material can be defined as an inorganic metal halide perovskite material. CsPbI3, CsPbCl3, and CsPbBr3 are non-limiting examples of inorganic metal halide perovskite materials.

[0037] As used in this article, the term "perovskite" also includes L2(ABX3). n-1 BX4 (which can also be written as L2A) n- 1B n X 3n+1 Any material with a layered structure, wherein L, A, and B are cations, X is an anion, and n is the number of BX4 monolayers disposed between two cations L. Figure 4 It depicts an L2(ABX3) configuration. n-1 Examples of layered perovskite materials with BX4 structures, where n has different values. For metal halide perovskite materials, component A can be a monovalent organic cation (such as methylamine hydrochloride (CH3NH3)). + ) or formamidin acetate (CH(NH2)2 + ), atomic cations (such as cesium (Cs) + )) or combinations thereof, where the L component can be an organic cation, such as 2-phenylethylamine hydrochloride (C6H5C2H4NH3) +) or 1-naphthylamine hydrochloride (C 10 H7CH2NH3 + Component B can be a divalent metal cation, such as lead (Pb). + ), Tin (Sn) + ), copper (Cu) + Europium (Eu) + ) or combinations thereof, and component X can be a halide anion, such as I - ,Br - Cl - Or combinations thereof. (C6H5C2H4NH3)2(CH(NH2)2PbBr3) n-1 PbBr4 and (C 10 H7CH2NH3)2(CH3NH3PbI2Br) n-1 PbI3Br is a non-limiting example of a metal halide perovskite material with a layered structure.

[0038] When the number of layers n is large, for example, n is greater than about 10, it has L2(ABX3). n-1 The layered perovskite material of BX4 employs a structure approximately equivalent to that of a 3D perovskite material with an ABX3 structure. As used herein, and as will generally be understood by those skilled in the art, perovskite materials with a large number of layers can be referred to as 3D perovskite materials, but it has been recognized that the dimensionality of such perovskite materials has decreased from n = ∞. In the case of the number of layers n = 1, it has an L2(ABX3) structure. n-1 The layered perovskite material of BX4 adopts a two-dimensional (2D) structure of L2BX4. Perovskite materials with a single layer can be referred to as 2D perovskite materials. When n is small, for example, n is in the range of approximately 2-10, it has an L2(ABX3) structure. n- The 1BX4 layered perovskite material exhibits a quasi-two-dimensional (quasi-2D) structure. Perovskite materials with a small number of layers can be referred to as quasi-2D perovskite materials. Due to quantum confinement effects, the band gap is lowest for layered perovskite structures where n is the highest.

[0039] Perovskite materials can have any number of layers. Perovskites can include 2D perovskite materials, quasi-2D perovskite materials, 3D perovskite materials, or combinations thereof. For example, a perovskite can comprise an assembly of layered perovskite materials with different numbers of layers. For example, a perovskite can comprise an assembly of quasi-2D perovskite materials with different numbers of layers.

[0040] As used herein, the term "perovskite" further includes films of perovskite materials. Films of perovskite materials can be crystalline, polycrystalline, or a combination thereof, having any number of layers and any range of grain or crystal size.

[0041] As used herein, the term "perovskite" further includes 3D perovskite structures or L2(ABX3) whose structures are equivalent to or similar to ABX3. n-1 BX4 represents a more general layered perovskite structure of perovskite nanocrystals. Perovskite nanocrystals can comprise perovskite nanoparticles, perovskite nanowires, perovskite nanosheets, or combinations thereof. Perovskite nanocrystals can have any shape or size, any number of layers, and any range of grain or crystal size. Figure 5 It depicts the L2(ABX3) region. n-1 Examples of perovskite nanocrystals with a similar layered structure to BX4, where n = 5 and L cations are arranged on the surface of the perovskite nanocrystals. The term "similar" is used because the distribution of L cations in perovskite nanocrystals can be similar to that of L2 (ABX3). n-1 The distribution of BX4 in perovskite materials with a formally layered structure differs. For example, in perovskite nanocrystals, a larger proportion of L cations can be arranged along the sides of the nanocrystals.

[0042] Several types of perovskite materials can be stimulated to emit light in response to optical or electrical excitation. That is, perovskite luminescent materials can be photoluminescent or electroluminescent. This terminology may differ slightly from that used in other sources. An example of a perovskite luminescent material that emits red light is lead methylammonium iodide (CH3NH3PbI3).

[0043] An example of a perovskite luminescent material that emits green light is formamidinium lead bromide (CH(NH2)2PbBr3). An example of a perovskite luminescent material that emits blue light is methylammonium lead chloride (CH3NH3PbCl3).

[0044] Typically, PeLED devices can be photoluminescent or electroluminescent. The term "PeLED" can be used to describe an electroluminescent device comprising a single emitting unit of electroluminescent perovskite luminescent material. The term "PeLED" can also be used to describe one or more emitting units of a stacked electroluminescent device comprising electroluminescent perovskite luminescent material. This terminology may differ slightly from that used in other sources.

[0045] As used herein, "top" means furthest from the substrate, and "bottom" means closest to the substrate. When describing the first layer as "placed" on top of the second layer, the first layer is placed further from the substrate. Unless the first and second layers are specified as "in contact," other layers may exist between the first and second layers.

[0046] As used herein, “solution-handleable” means capable of dissolving, dispersing or transporting in a liquid medium in solution or suspension and / or capable of depositing from a liquid medium.

[0047] As used herein, and as will generally be understood by those skilled in the art, if the first energy level is closer to the vacuum level, then the first “highest occupied molecular orbital” (HOMO) or “lowest unoccupied molecular orbital” (LUMO) energy level is “greater” or “higher” than the second HOMO or LUMO energy level. Since ionization potential (IP) and electron affinity (EA) are measured as negative energies relative to the vacuum level, a higher HOMO energy level corresponds to a smaller negative IP. Similarly, a higher LUMO energy level corresponds to a smaller negative EA. On a conventional energy level diagram, with the vacuum level at the top, the LUMO energy level of the material is higher than the HOMO energy level of the same material. A “higher” HOMO or LUMO energy level appears to be closer to the top of this diagram than a “lower” HOMO or LUMO energy level.

[0048] As used herein, and as will generally be understood by those skilled in the art, a first work function is “greater than” or “higher than” a second work function if it has a higher absolute value. This is because work functions are typically measured as negative relative to the vacuum level, meaning that the “higher” the work function, the greater its negativity. On a conventional energy level diagram, with the vacuum level at the top, a “higher” work function is shown as being further away from the vacuum level in the downward direction. Therefore, the definitions of HOMO and LUMO levels follow a different convention than those for work functions.

[0049] As used herein, and as will be generally understood by those skilled in the art, a light-emitting device such as PeLED, OLED, or QLED can be referred to as a “stacked” light-emitting device if two or more emitting units are separated by one or more charge-generating layers within the layered structure of the light-emitting device. In some sources, a stacked light-emitting device may be referred to as a series light-emitting device. It should be understood that the terms “stacked” and “series” are used interchangeably, and as used herein, a series light-emitting device is also considered a stacked light-emitting device. This terminology may differ slightly from that used in other sources.

[0050] As used herein, the terms “OLED,” “QLED,” and “PeLED” can be used to describe a single-emitting-unit electroluminescent device comprising electroluminescent organic light-emitting materials, quantum dot light-emitting materials, and perovskite light-emitting materials, respectively. The terms “OLED,” “QLED,” and “PeLED” can also be used to describe one or more emitting units of a stacked electroluminescent device comprising electroluminescent organic light-emitting materials, quantum dot light-emitting materials, and perovskite light-emitting materials, respectively.

[0051] As used herein, the term "optically coupled" means that one or more elements of a device or structure are arranged such that light can pass between the one or more elements. The one or more elements may be in contact or may be separated by gaps or any connection, coupling, link, etc., that allows light to pass between the one or more elements. For example, one or more subpixels within a pixel arrangement of a display may be optically coupled to one or more color-changing layers, such as color conversion layers and color filters. Summary of the Invention

[0052] This invention provides an apparatus. In one embodiment, the apparatus includes a stacked blue light emitting device, comprising: a first electrode; a second electrode; a first emitting unit including a first emitting layer; a second emitting unit including a second emitting layer; and a first charge generating layer; wherein the first emitting unit, the second emitting unit, and the first charge generating layer are all disposed between the first electrode and the second electrode; the first emitting unit is disposed above the first electrode; the first charge generating layer is disposed above the first emitting unit; the second emitting unit is disposed above the first charge generating layer; and the second electrode is disposed above the second emitting unit; the first emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm, the peak wavelength being defined as a first peak wavelength; the first emitting unit emits blue light with chromaticity coordinates (x1, y1) in a first CIE 1931 (x, y) color space; the second emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm, the peak wavelength being defined as a second peak wavelength; and the second emitting unit emits blue light having a second chromaticity, the second chromaticity being defined as a second CIE 1931 (x, y) color space. The chromaticity coordinates of the 1931(x,y) color space are (x2,y2); the second chromaticity is substantially different from the first chromaticity; and the first and second emission layers include organic light-emitting materials, quantum dot light-emitting materials and / or perovskite light-emitting materials.

[0053] In one embodiment, the second chromaticity coordinates (x2, y2) are not contained within a first-order McAdam ellipse centered at the first chromaticity coordinates (x1, y1). In one embodiment, the second chromaticity coordinates (x2, y2) are not contained within a third-order McAdam ellipse centered at the first chromaticity coordinates (x1, y1). In one embodiment, the second peak wavelength is at least 4 nm larger or at least 4 nm smaller than the first peak wavelength. In one implementation, the chromaticity coordinates (x1, y1) of the first CIE 1931 (x, y) color space can be converted to the chromaticity coordinates (u1, v1) of the first CIE 1976 (u', v') color space; and the chromaticity coordinates (x2, y2) of the second CIE 1931 (x, y) color space can be converted to the chromaticity coordinates (u2, v2) of the second CIE 1976 (u', v') color space; wherein the first chromaticity coordinates (u1, v1) and the second chromaticity coordinates (u2, v2) are sufficiently different such that the chromaticity difference defined by Δuv is 0.010 or greater.

[0054] In one embodiment, the first emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm; and the second emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm.

[0055] In one embodiment, the first emitting unit emits blue light with a CIE 1931y coordinate of 0.080 or less; and the second emitting unit emits blue light with a CIE 1931y coordinate greater than 0.080.

[0056] In one embodiment, the first and second emitting layers comprise organic light-emitting materials. In one embodiment, at least one of the first and second emitting layers comprises a phosphorescent organic light-emitting material; and at least one of the first and second emitting layers comprises a fluorescent organic light-emitting material. In one embodiment, the first and second emitting layers comprise quantum dot light-emitting materials. In one embodiment, the first and second emitting layers comprise perovskite light-emitting materials. In one embodiment, the first emitting layer comprises a first type of light-emitting material, which is an organic light-emitting material, a quantum dot light-emitting material, or a perovskite light-emitting material; the second emitting layer comprises a second type of light-emitting material, which is an organic light-emitting material, a quantum dot light-emitting material, or a perovskite light-emitting material; and the second type of light-emitting material is different from the first type of light-emitting material.

[0057] In one embodiment, the first transmitting unit and the second transmitting unit are independently addressable and can emit light independently of each other. In another embodiment, the first transmitting unit and the second transmitting unit are jointly addressable and can emit light not independently of each other.

[0058] In one embodiment, the stacked blue light emitting device further includes: a third emitting unit comprising a third emitting layer; and a second charge generating layer; wherein the third emitting unit and the second charge generating layer are disposed between the second emitting unit and a second electrode; the second charge generating layer is disposed above the second emitting unit; the third emitting unit is disposed above the second charge generating layer; the second electrode is disposed above the third emitting unit; the third emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm, the peak wavelength being defined as the third peak wavelength; the third emitting unit emits blue light with chromaticity coordinates (x3, y3) in a first CIE 1931 (x, y) color space; and the third emitting layer comprises an organic light-emitting material, a quantum dot light-emitting material, or a perovskite light-emitting material.

[0059] In one embodiment, the third chromaticity is substantially the same as one of the first and second chromaticities; and the third chromaticity is substantially different from one of the first and second chromaticities. In one embodiment, the third transmitting unit is co-addressed with one of the first and second transmitting units and may emit light not independently of one of the first and second transmitting units; and the third transmitting unit is addressed independently of one of the first and second transmitting units and may emit light independently of one of the first and second transmitting units. In one embodiment, the third transmitting unit is co-addressed with one of the first and second transmitting units and may emit light not independently of one of the first and second transmitting units; the third transmitting unit is addressed independently of one of the first and second transmitting units and may emit light independently of one of the first and second transmitting units; wherein the transmitting unit co-addressed with the third transmitting unit has a chromaticity substantially the same as the third transmitting unit; and the transmitting unit addressed independently of the third transmitting unit has a chromaticity substantially different from the third transmitting unit.

[0060] In one embodiment, the device is part of a lighting panel. In another embodiment, the device is part of a display.

[0061] A display is provided. In one embodiment, the display includes: a first sub-pixel configured to emit red light in the visible spectrum with a peak wavelength in the range of 580 nm to 780 nm; a second sub-pixel configured to emit green light in the visible spectrum with a peak wavelength in the range of 500 nm to 580 nm; and a third sub-pixel configured to emit blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm; wherein the first sub-pixel includes a first stacked blue light emitting device optically coupled to a red color conversion layer; the second sub-pixel includes a second stacked blue light emitting device optically coupled to a green color conversion layer; and the third sub-pixel includes a third stacked blue light emitting device; wherein all first stacked blue light emitting devices... Both the second and third stacked blue light emitting devices include: a first electrode; a second electrode; a first emitting unit, which includes a first emitting layer; a second emitting unit, which includes a second emitting layer; and a first charge generating layer; wherein the first emitting unit, the second emitting unit, and the first charge generating layer are all disposed between the first electrode and the second electrode; the first emitting unit is disposed above the first electrode; the first charge generating layer is disposed above the first emitting unit; the second emitting unit is disposed above the first charge generating layer; and the second electrode is disposed above the second emitting unit; the first emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm, and this peak wavelength is defined as the first peak wavelength; the first emitting unit emits a first CIE... The first emission layer emits blue light with chromaticity coordinates (x1, y1) in the CIE 1931(x,y) color space; the second emission unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm, which is defined as the second peak wavelength; the second emission unit emits blue light with a second chromaticity, the second chromaticity having chromaticity coordinates (x2, y2) in the second CIE 1931(x,y) color space; the second chromaticity is substantially different from the first chromaticity; and the first emission layer and the second emission layer include organic light-emitting materials, quantum dot light-emitting materials and / or perovskite light-emitting materials.

[0062] In one embodiment, for all the first, second, and third stacked blue light emitting devices, the second chromaticity coordinates (x2, y2) are not contained within a first-order McAdam ellipse centered at the first chromaticity coordinates (x1, y1). In one embodiment, for all the first, second, and third stacked blue light emitting devices, the second chromaticity coordinates (x2, y2) are not contained within a third-order McAdam ellipse centered at the first chromaticity coordinates (x1, y1). In one embodiment, for all the first, second, and third stacked blue light emitting devices, the second peak wavelength is at least 4 nm larger or at least 4 nm smaller than the first peak wavelength. In one embodiment, for all the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices, the first CIE 1931(x,y) color space chromaticity coordinates (x1,y1) can be converted to the first CIE 1976(u',v') color space chromaticity coordinates (u1,v1); and the second CIE 1931(x,y) color space chromaticity coordinates (x2,y2) can be converted to the second CIE1976(u',v') color space chromaticity coordinates (u2,v2); wherein the first chromaticity coordinates (u1,v1) and the second chromaticity coordinates (u2,v2) are sufficiently different such that the chromaticity difference defined by Δuv is 0.010 or greater.

[0063] In one embodiment, for all the first, second, and third stacked blue light emitting devices, the first emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm; and the second emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm.

[0064] In one embodiment, for all the first, second, and third stacked blue light emitting devices, the first emitting unit emits blue light with a CIE 1931y coordinate of 0.080 or less; and the second emitting unit emits blue light with a CIE 1931y coordinate greater than 0.080. In another embodiment, for all the first, second, and third stacked blue light emitting devices, the first emitting unit emits blue light with a CIE 1931y coordinate greater than 0.080; and the second emitting unit emits blue light with a CIE 1931y coordinate of 0.080 or less.

[0065] In one embodiment, for all first-stacked, second-stacked, and third-stacked blue light emitting devices, the first and second emitting layers comprise organic light-emitting materials. In one embodiment, for all first-stacked, second-stacked, and third-stacked blue light emitting devices, at least one of the first and second emitting layers comprises a phosphorescent organic light-emitting material; and at least one of the first and second emitting layers comprises a fluorescent organic light-emitting material. In one embodiment, for all first-stacked, second-stacked, and third-stacked blue light emitting devices, the first and second emitting layers comprise quantum dot light-emitting materials. In one embodiment, for all first-stacked, second-stacked, and third-stacked blue light emitting devices, the first and second emitting layers comprise perovskite light-emitting materials. In one embodiment, for all the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices, the first emitting layer includes a first type of luminescent material, which is an organic luminescent material, a quantum dot luminescent material, or a perovskite luminescent material; the second emitting layer includes a second type of luminescent material, which is an organic luminescent material, a quantum dot luminescent material, or a perovskite luminescent material; and the second type of luminescent material is different from the first type of luminescent material.

[0066] In one implementation, the first stacked blue light emitting device, the second stacked blue light emitting device, and the third stacked blue light emitting device all have the same device architecture.

[0067] In one embodiment, for any one of the first stacked blue light emitting device, the second stacked blue light emitting device, and the third stacked blue light emitting device, the first emitting unit and the second emitting unit are independently addressable and can emit light independently of each other. In another embodiment, for any one of the first stacked blue light emitting device, the second stacked blue light emitting device, and the third stacked blue light emitting device, the first emitting unit and the second emitting unit are jointly addressable and can emit light not independently of each other.

[0068] In one embodiment, for all the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices, the first emitting unit and the second emitting unit are independently addressable and can emit light independently of each other. In another embodiment, for all the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices, the first emitting unit and the second emitting unit are jointly addressable and can emit light not independently of each other.

[0069] In one embodiment, the first and second emitting units of the third stacked blue light emitting device are independently addressable and can emit light independently of each other; and the first and second emitting units of the first stacked blue light emitting device are jointly addressable and can emit light not independently of each other; and the first and second emitting units of the second stacked blue light emitting device are jointly addressable and can emit light not independently of each other.

[0070] In one embodiment, all the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices further include: a third emitting unit, the third emitting unit including a third emitting layer; and a second charge generating layer; wherein the third emitting unit and the second charge generating layer are disposed between the second emitting unit and a second electrode; the second charge generating layer is disposed above the second emitting unit; the third emitting unit is disposed above the second charge generating layer; and the second electrode is disposed above the third emitting unit; and the third emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm, the peak wavelength being defined as the third peak wavelength; the third emitting unit emits blue light with a third chromaticity, the third chromaticity having chromaticity coordinates of the third CIE 1931(x,y) color space as (x3,y3); and the third emitting layer includes an organic light-emitting material, a quantum dot light-emitting material, or a perovskite light-emitting material.

[0071] In one embodiment, for all the first, second, and third stacked blue light emitting devices, the third chromaticity is substantially the same as one of the first and second chromaticities; and the third chromaticity is substantially different from one of the first and second chromaticities. In one embodiment, for all the first, second, and third stacked blue light emitting devices, the third emitting unit is co-addressed with one of the first and second emitting units and can emit light not independently of one of the first and second emitting units; and the third emitting unit is addressed independently of one of the first and second emitting units and can emit light independently of one of the first and second emitting units.

[0072] In one embodiment, for all the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices, the third emitting unit is co-addressed with one of the first emitting units and the second emitting unit and can emit light not independently of one of the first emitting units and the second emitting unit; the third emitting unit is addressed independently of one of the first emitting units and the second emitting unit and can emit light independently of one of the first emitting units and the second emitting unit; wherein the emitting unit co-addressed with the third emitting unit has substantially the same chromaticity as the third emitting unit; and the emitting unit addressed independently of the third emitting unit has substantially different chromaticity from the third emitting unit.

[0073] In one implementation, the display is part of a consumer product. Attached Figure Description

[0074] The above-described invention and the following detailed description of illustrative embodiments will be better understood when read in conjunction with the accompanying drawings. Exemplary constructions of this disclosure are shown in the drawings for illustrative purposes. However, this disclosure is not limited to the specific methods and tools disclosed herein. Furthermore, those skilled in the art will understand that the drawings are not drawn to scale.

[0075] In the accompanying drawings, underlined numbers are used to indicate the item located by the underlined number or the item adjacent to the underlined number. Ununderlined numbers relate to items identified by lines connecting the ununderlined number to the item. When a number is ununderlined and has an associated arrow, the ununderlined number is used to identify the regular item pointed to by the arrow. Embodiments of this disclosure will now be described by way of example and with reference to the following drawings:

[0076] Figure 1 The light-emitting device is depicted.

[0077] Figure 2An inverted light-emitting device is depicted.

[0078] Figure 3 A 3D perovskite luminescent material with the structure ABX3 was described.

[0079] Figure 4 The structure L2(ABX3) is depicted. n-1 BX4 is a layered perovskite luminescent material where n = 1, 3, 5, 10 and ∞.

[0080] Figure 5 It depicts a structure with L2(ABX3). n-1 Examples of nanocrystals of perovskite materials with a layered structure similar to BX4, where n = 5.

[0081] Figure 6 A stacked light-emitting device with two emitting units is depicted.

[0082] Figure 7 A stacked light-emitting device with three emitting units is depicted.

[0083] Figure 8 The layers of a stacked light-emitting device with two emitting units are depicted.

[0084] Figure 9 The layers of a stacked light-emitting device with three emitting units are depicted.

[0085] Figure 10 It depicts the reproduction of the chromaticity diagram of the CIE 1931(x,y) color space.

[0086] Figure 11 A reproduction of the chromaticity diagram of the CIE 1931(x,y) color space is depicted, and the color gamuts of (a) DCI-P3 and (b) Rec.2020 color spaces are also shown.

[0087] Figure 12 A reproduction of the chromaticity diagram of the CIE 1931(x,y) color space is depicted, which also shows the color gamut of (a) DCI-P3 and (b) Rec.2020 color spaces, where the color coordinates are for an exemplary blue device.

[0088] Figure 13 A reproduction of the chromaticity diagram of the CIE 1931(x,y) color space is depicted, which also shows the 10th-order McAdam ellipse.

[0089] Figure 14 An exemplary electroluminescence emission spectrum of a blue light emitting device is depicted using a function of photoluminescence efficiency.

[0090] Figure 15Various configurations of the emission units of a stacked blue light emitting device with two blue emission units are depicted.

[0091] Figure 16 Various configurations of the emission units of a stacked blue light emitting device with three blue emission units are depicted.

[0092] Figure 17 An exemplary design for red, green, and blue subpixels applied to a display is depicted.

[0093] Figure 18 An exemplary RGB OLED display architecture is described.

[0094] Figure 19 An exemplary RGBW OLED display architecture is described.

[0095] Figure 20 An exemplary QD-OLED display architecture is described.

[0096] Figure 21 An exemplary QD-OLED display architecture including two blue emitting units is depicted.

[0097] Figure 22 An improved QD-OLED display architecture including three blue emission units is described. Detailed Implementation

[0098] This invention relates to OLEDs, QLEDs, and PeLEDs. The device architecture and operating principles of OLEDs, QLEDs, and PeLEDs are substantially similar. Each of these light-emitting devices includes at least one emitting layer disposed between and electrically connected to the anode and cathode. For OLEDs, the emitting layer comprises an organic light-emitting material. For QLEDs, the emitting layer comprises a quantum dot light-emitting material. For PeLEDs, the emitting layer comprises a perovskite light-emitting material. For each of these light-emitting devices, when a current is applied, holes are injected into the anode, while electrons are injected into one or more emitting layers at the cathode. The injected holes and electrons migrate toward electrodes with opposite charges. When electrons and holes are localized, excitons can be formed as localized electron-hole pairs with excited energy states. If the excitons relax through a photoemission mechanism, light is emitted. Non-radiative mechanisms, such as thermal radiation and / or Auger recombination, may also occur, but are generally considered undesirable. The substantial similarity between the device architectures and operating principles required for OLED, QLED, and PeLED facilitates the combination of organic light-emitting materials, quantum dot light-emitting materials, and perovskite light-emitting materials in a single light-emitting device.

[0099] Figure 1A light-emitting device 100 with a single emitting unit is shown. The light-emitting device 100 can be an OLED, QLED, or PeLED. The device 100 may include a substrate 110, an anode 115, a hole injection layer 120, a hole transport layer 125, an electron blocking layer 130, an emitting layer 135, a hole blocking layer 140, an electron transport layer 145, an electron injection layer 150, a cathode 155, and a barrier layer 160. The device 100 can be fabricated by sequentially depositing the described layers. Because the device 100 has an anode 115 disposed below the cathode 155, the device 100 can be referred to as a "standard" device architecture. For OLEDs, the emitting layer comprises an organic light-emitting material. For QLEDs, the emitting layer comprises a quantum dot light-emitting material. For PeLEDs, the emitting layer comprises a perovskite light-emitting material.

[0100] Figure 2 An inverted light-emitting device 200 with a single emitting unit is shown. The light-emitting device 200 can be an OLED, QLED, or PeLED. The device includes a substrate 210, a cathode 215, an emitting layer 220, a hole transport layer 225, and an anode 230. The device 200 can be fabricated by sequentially depositing the layers described herein. Because the device 200 has a cathode 215 disposed below the anode 230, the device 200 can be referred to as an "inverted" device architecture. For OLEDs, the emitting layer comprises an organic light-emitting material. For QLEDs, the emitting layer comprises a quantum dot light-emitting material. For PeLEDs, the emitting layer comprises a perovskite light-emitting material. Materials similar to those described with respect to device 100 can be used in the corresponding layers of device 200. Figure 2 An example is provided on how some layers can be omitted from the structure of OLED, QLED, or PeLED.

[0101] Figure 1 and Figure 2 The simple layered structure shown is provided by way of non-limiting example, and it should be understood that embodiments of the invention can be used in combination with a variety of other structures. The specific materials and structures described are exemplary in nature, and other materials and structures can be used. Functional OLEDs, QLEDs, and PeLEDs can be realized by combining the described layers in different ways, or layers can be omitted entirely, depending on factors such as performance, design, and cost. Other layers not specifically described may also be included. Materials other than those specifically described may be used. Although many examples provided herein describe the layers as comprising a single material, it should be understood that combinations of materials can be used. Moreover, layers may have sublayers. The names given to the layers herein are not intended to be strictly limiting. For example, in a device, a hole transport layer can transport holes and inject holes into an emitter layer, and can be described as a hole transport layer or a hole injection layer.

[0102] OLEDs, PeLEDs, and QLEDs are typically designed to emit light through at least one of the electrodes, and one or more transparent electrodes can be used in such optoelectronic devices. For example, a transparent electrode material such as indium tin oxide (ITO) can be used for the bottom electrode, while a transparent electrode material such as a thin metal layer of a magnesium and silver blend (Mg:Ag) can be used for the top electrode. For devices designed to emit light only through the bottom electrode, the top electrode does not need to be transparent and can contain opaque and / or reflective layers, such as a metal layer with high reflectivity. Similarly, for devices designed to emit light only through the top electrode, the bottom electrode can be opaque and / or reflective, such as a metal layer with high reflectivity. When the electrodes do not need to be transparent, using thicker layers can provide better conductivity and reduce voltage drop and / or Joule heating in the device, and using reflective electrodes can increase the amount of light emitted through the other electrodes by reflecting light backward toward the transparent electrodes. Completely transparent devices, where both electrodes are transparent, can also be fabricated.

[0103] The device manufactured according to embodiments of the present invention may optionally include a substrate 110. The substrate 110 may comprise any suitable material providing the desired structural and optical properties. The substrate 110 may be rigid or flexible. The substrate 110 may be flat or curved. The substrate 110 may be transparent, translucent, or opaque. Preferred substrate materials are glass, plastic, and metal foil. Other substrates, such as fabric and paper, may be used. The material and thickness of the substrate 110 can be selected to obtain the desired structural and optical properties.

[0104] Devices manufactured according to embodiments of the present invention may optionally include an anode 115. The anode 115 may include any suitable material or combination of materials known in the art, such that the anode 115 is capable of conducting and injecting holes into the layers of the device. Preferred anode 115 materials include: conductive metal oxides such as indium tin oxide (ITO), indium zinc oxide (IZO), and zinc aluminum oxide (AlZnO); metals such as silver (Ag), aluminum (Al), neodymium aluminum (Al:Nd), gold (Au), and alloys thereof; or combinations thereof. Other preferred anode 115 materials include graphene, carbon nanotubes, nanowires or nanoparticles, silver nanowires or nanoparticles, organic materials such as poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS), and derivatives thereof, or combinations thereof. Composite anodes comprising one or more anode materials in a single layer may be preferred for some devices. Multilayer anodes comprising one or more anode materials in one or more layers may be preferred for some devices. An example of a multilayer anode is ITO / Ag / ITO. In standard device architectures used in OLEDs, QLEDs, and PeLEDs, the anode 115 can be transparent enough to create a bottom-emitting device in which light is emitted through the substrate. One example of a transparent anode commonly used in standard device architectures is a layer of ITO. Another example of a transparent anode commonly used in standard device architectures is ITO / Ag / ITO in which the Ag thickness is less than about 25 nm. By including a silver layer less than about 25 nm thick, the anode can be transparent and partially reflective. When this transparent and partially reflective anode is used in combination with a reflective cathode such as LiF / Al, it has the advantage of creating microcavities within the device. Microcavities can provide one or more of the following advantages: an increased total amount of light emitted from the device, and therefore higher efficiency and brightness; an increased proportion of light emitted in the forward direction, and therefore increased apparent brightness at normal incidence; and a narrower emission spectrum, resulting in light emission with increased color saturation. The anode 115 can be opaque and / or reflective. In standard device architectures for OLEDs, QLEDs, and PeLEDs, the reflective anode 115 may be preferred for some top-emitting devices used to increase the amount of light emitted from the top of the device. An example of a reflective anode commonly used in standard device architectures is a multilayer anode of ITO / Ag / ITO in which the Ag thickness is greater than approximately 80 nm. When this reflective anode is used in combination with a transparent and partially reflective cathode such as Mg:Ag, it has the advantage of creating microcavities within the device. The material and thickness of the anode 115 can be selected to obtain the desired conductivity and optical properties. In the case of a transparent anode 115, for a given material, a range of thicknesses can be achieved that is thick enough to provide the desired conductivity, but thin enough to provide the desired transparency. Other materials and structures can be used.

[0105] The apparatus manufactured according to embodiments of the present invention may optionally include a hole transport layer 125. The hole transport layer 125 may contain any material capable of transporting holes. The hole transport layer 125 may be deposited by a solution process or by a vacuum deposition process. The hole transport layer 125 may be doped or undoped. Doping may be used to enhance conductivity.

[0106] Examples of undoped hole transport layers are N,N'-bis(1-naphthyl)-N,N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine (NPD), poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine)(TFB), poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)-biphenylamine](poly-TPD), and poly(9-vinylcarbazole) (…). PVK), 4,4'-bis(N-carbazolyl)-1,1'-biphenyl (CBP), spiro-OMeTAD, and molybdenum oxide (MoO3). An example of a doped hole transport layer is 4,4',4”-tris[phenyl(m-tolyl)amino]triphenylamine (m-MTDATA) doped with F4-TCNQ at a molar ratio of 50:1. An example of a solution-treated hole transport layer is PEDOT:PSS. Other hole transport layers and structures can be used.

[0107] An apparatus manufactured according to an embodiment of the invention may optionally include an emitting layer 135. The emitting layer 135 may contain any material capable of emitting light when an electric current is transmitted between the anode 115 and the cathode 155.

[0108] Several examples of fluorescent organic light-emitting materials are described in European Patent EP 0423283 B1. Several examples of phosphorescent organic light-emitting materials are described in US Patent 6303238 B1 and US Patent 7279704 B2. Several examples of organic light-emitting materials emitting via the TADF mechanism are described in Uoyama et al.

[0109] Several examples of quantum dot luminescent materials are described in Kathirgamanathan et al. All of these citations are incorporated herein by reference in their entirety.

[0110] Examples of perovskite luminescent materials include 3D perovskite materials such as methylammonium lead iodide (CH3NH3PbI3), methylammonium lead bromide (CH3NH3PbBr3), methylammonium lead chloride (CH3NH3PbCl3), formamidinium lead iodide (CH(NH2)2PbI3), formamidinium lead bromide (CH(NH2)2PbBr3), formamidinium lead chloride (CH(NH2)2PbCl3), cesium lead iodide (CsPbI3), cesium lead bromide (CsPbBr3), and cesium lead chloride (CsPbCl3). Examples of perovskite luminescent materials further include 3D perovskite materials having mixed halides, such as CH3NH3PbI... 3-x Cl x CH3NH3PbI 3-x Br x CH3NH3PbCl 3-x Br x CH(NH2)2PbI 3-x Br x CH(NH2)2PbI 3- x Cl x CH(NH2)2PbCl 3-x Br x CsPbI 3-x Cl x CsPbI 3-x Br x and CsPbCl 3-x Br x Where x is in the range of 0-3. Examples of perovskite luminescent materials further include 2D perovskite materials, such as (C 10 H7CH2NH3)2PbI4、(C 10 H7CH2NH3)2PbBr4、(C 10 (C7CH2NH3)2PbCl4, (C6H5C2H4NH3)2PbI4, (C6H5C2H4NH3)2PbBr4 and (C6H5C2H4NH3)2PbCl4; 2D perovskite materials with mixed halides, such as (C7CH2NH3)2PbCl4, (C6H5C2H4NH3)2PbI4, (C6H5C2H4NH3)2PbBr4 and (C6H5C2H4NH3)2PbCl4; 10 H7CH2NH3)2PbI 4-x Cl x (C) 10 H7CH2NH3)2PbI 4-x Br x (C) 10 H7CH2NH3)2PbCl 4-x Br x (C6H5C2H4NH3)2PbI 4-x Cl x(C6H5C2H4NH3)2PbI 4-x Br x and (C6H5C2H4NH3)2PbCl 4-x Br x Where x is in the range of 0-4. Examples of perovskite luminescent materials further include quasi-2D perovskite materials, such as (C6H5C2H4NH3)2(CH(NH2)2PbBr3). n-1 PbI4、(C6H5C2H4NH3)2(CH(NH2)2PbBr3) n-1 PbBr4, (C6H5C2H4NH3)2(CH(NH2)2PbBr3) n-1 PbCl4、(C 10 H7CH2NH3)2(CH3NH3PbI2Br) n-1 PbI4、(C 10 H7CH2NH3)2(CH3NH3PbI2Br) n-1 PbBr4 and (C 10 H7CH2NH3)2(CH3NH3PbI2Br) n-1 PbCl4, where n is the number of layers, and optionally, n can be in the range of about 2-10. Examples of perovskite luminescent materials further include quasi-2D perovskite materials with mixed halides, such as (C6H5C2H4NH3)2(CH(NH2)2PbBr3). n-1 PbI 4-x Cl x , (C6H5C2H4NH3)2(CH(NH2)2PbBr3) n-1 PbI 4-x Br x , (C6H5C2H4NH3)2(CH(NH2)2PbBr3) n-1 PbCl 4-x Br x (C) 10 H7CH2NH3)2(CH3NH3PbI2Br) n-1 PbI 4-x Cl x (C) 10 H7CH2NH3)2(CH3NH3PbI2Br) n-1 PbI 4-x Br x and (C) 10 H7CH2NH3)2(CH3NH3PbI2Br) n-1 PbCl 4-x Br x, where n is the number of layers, and optionally, n can be in the range of about 2-10, and x is in the range of 0-4. Examples of perovskite luminescent materials further include any of the foregoing examples, wherein the divalent metal cation lead (Pb) + Tin (Sn) can be used + ), copper (Cu) + or europium (Eu) + Instead, examples of perovskite luminescent materials further include perovskite luminescent nanocrystals having a structure very similar to that of quasi-2D perovskite materials.

[0111] Perovskite luminescent materials can include organometal halide perovskite materials in which organic cations are included, such as methylammonium lead iodide (CH3NH3PbI3), methylammonium lead bromide (CH3NH3PbBr3), and methylammonium lead chloride (CH3NH3PbCl3). Perovskite luminescent materials can also include inorganic metal halide perovskite materials in which inorganic cations are included, such as cesium lead iodide (CsPbI3), cesium lead bromide (CsPbBr3), and cesium lead chloride (CsPbCl3). Furthermore, perovskite luminescent materials can include perovskite luminescent materials in which a combination of organic and inorganic cations is present. The choice of organic or inorganic cations can be determined by several factors, including the desired emission color, electroluminescence efficiency, electroluminescence stability, and ease of handling. Inorganic metal halide perovskite materials are particularly suitable for perovskite luminescent materials with nanocrystalline structures, such as... Figure 5 The perovskite luminescent material described herein allows for the realization of a compact and stable perovskite luminescent nanocrystal structure by inorganic cations.

[0112] The perovskite luminescent material can be included in the emitting layer 135 in a variety of ways. For example, the emitting layer may include a 2D perovskite luminescent material, a quasi-2D perovskite luminescent material, or a 3D perovskite luminescent material, or a combination thereof. Optionally, the emitting layer may include perovskite luminescent nanocrystals. Optionally, the emitting layer 135 may include an integrator of quasi-2D perovskite luminescent material, wherein the quasi-2D perovskite luminescent material in the integrator may include different numbers of layers. An integrator of quasi-2D perovskite luminescent material may be preferred because there may be energy transfer from a quasi-2D perovskite luminescent material with fewer layers and a larger band gap to a quasi-2D perovskite luminescent material with more layers and a lower band gap. This energy funnel can effectively confine excitons in the PeLED device and can improve device performance. Optionally, the emitting layer 135 may include perovskite luminescent nanocrystal material. Perovskite luminescent nanocrystal material may be preferred because nanocrystal boundaries can be used to confine excitons in the PeLED device, and surface cations can be used to passivate the nanocrystal boundaries. Exciton confinement and surface passivation can improve device performance. Other emitter layer materials and structures can be used.

[0113] The device manufactured according to an embodiment of the invention may optionally include an electron transport layer 145. The electron transport layer 145 may comprise any material capable of transporting electrons. The electron transport layer 145 may be deposited by a solution process or by a vacuum deposition process. The electron transport layer 145 may be doped or undoped. Doping may be used to enhance conductivity.

[0114] Examples of undoped electron transport layers include tris(8-hydroxyquinoline)aluminum (Alq3), 2,2',2”-(1,3,5-phenyltriyl)-tris(1-phenyl-1-H-benzimidazole) (TPBi), 2,9-dimethyl-4,7-diphenyl-1,10-o-phenanthroline (BCP), zinc oxide (ZnO), and titanium dioxide (TiO3). An example of a doped electron transport layer is 4,7-diphenyl-1,10-o-phenanthroline (BPhen) doped with lithium (Li) in a 1:1 molar ratio. An example of a solution-treated electron transport layer is methyl [6,6]-phenyl C61-butyrate (PCBM). Other electron transport layers and structures can be used.

[0115] Devices manufactured according to embodiments of the present invention may optionally include a cathode 155. The cathode 155 may include any suitable material or combination of materials known in the art, such that the cathode 155 is capable of conducting and injecting electrons into the layers of the device. Preferred cathode 155 materials include: metal oxides, such as indium tin oxide (ITO), indium zinc oxide (IZO), and fluorine tin oxide (FTO); metals, such as calcium (Ca), barium (Ba), magnesium (Mg), and ytterbium (Yb), or combinations thereof. Other preferred cathode 155 materials include metals, such as silver (Ag), aluminum (Al), aluminum neodymium (Al:Nd), gold (Au), and alloys thereof, or combinations thereof. Composite cathodes comprising one or more cathode materials in a single layer may be preferred for some devices. An example of a composite cathode is Mg:Ag. Multilayer cathodes comprising one or more cathode materials in one or more layers may be preferred for some devices. An example of a multilayer cathode is Ba / Al. In standard device architectures for OLEDs, QLEDs, and PeLEDs, the cathode 155 may be transparent enough to produce a top-emitting device in which light is emitted from the top of the device. An example of a transparent cathode commonly used in standard device architectures is a Mg:Ag composite layer. By using a Mg:Ag compound, the cathode can be both transparent and partially reflective. When such a transparent and partially reflective cathode is used in combination with a reflective anode (such as ITO / Ag / ITO) in which the Ag thickness is greater than about 80 nm, it has the advantage of creating microcavities within the device. Cathode 155 can be opaque and / or reflective. In standard device architectures for OLEDs, QLEDs, and PeLEDs, reflective cathode 155 may be preferred for some bottom-emitting devices used to increase the amount of light emitted from the bottom of the device through the substrate. An example of a reflective cathode commonly used in standard device architectures is a LiF / Al multilayer cathode. When such a reflective cathode is used in combination with a transparent and partially reflective anode (such as ITO / Ag / ITO) in which the Ag thickness is less than about 25 nm, it has the advantage of creating microcavities within the device.

[0116] The material and thickness of the cathode 155 can be selected to obtain the desired conductive and optical properties. When the cathode 155 is transparent, for a given material, a range of thicknesses can be achieved—thick enough to provide the desired conductivity, but thin enough to provide the desired transparency. Other materials and structures can also be used.

[0117] Devices manufactured according to embodiments of the present invention may optionally include one or more barrier layers. The barrier layers can be used to reduce the number of charge carriers (electrons or holes) and / or excitons exiting the emitter layer. An electron barrier layer 130 may be disposed between the emitter layer 135 and the hole transport layer 125 to prevent electrons from leaving the emitter layer 135 in the direction of the hole transport layer 125. Similarly, a hole barrier layer 140 may be disposed between the emitter layer 135 and the electron transport layer 145 to prevent holes from leaving the emitter layer 135 in the direction of the electron transport layer 145. The barrier layer can also be used to prevent excitons from diffusing from the emitter layer. As used herein, and as those skilled in the art will understand, the term "barrier layer" means that the layer provides a barrier that significantly suppresses the transport of charge carriers and / or excitons, without implying that the layer completely blocks charge carriers and / or excitons. The presence of this barrier layer in the device can produce substantially higher efficiency compared to similar devices lacking a barrier layer. The barrier layer can also be used to confine emission to a desired region of the device.

[0118] An apparatus manufactured according to embodiments of the present invention may optionally include one or more injection layers. Typically, the injection layer contains one or more materials that can improve the injection of charge carriers from one layer (such as an electrode) to an adjacent layer. The injection layer may also perform charge transport functions.

[0119] In device 100, the hole injection layer 120 can be any layer that improves hole injection from the anode 115 to the hole transport layer 125. Examples of materials that can be used as the hole injection layer are copper phthalocyanine (II) (CuPc) and 1,4,5,8,9,11-hexaazabenzophenanthrene (HATCN), which can be deposited in the vapor phase, as well as polymers such as PEDOT:PSS that can be deposited from solution. Another example of a material that can be used as the hole injection layer is molybdenum oxide (MoO3).

[0120] Hole injection layer (HIL) 120 may include a charge-bearing component having a HOMO energy level as defined herein by its relative IP energy level, advantageously matching the adjacent anode layer on one side of the HIL and the hole transport layer on the opposite side of the HIL. The “charge-bearing component” is the material responsible for the HOMO energy level that actually transports holes. This material may be the substrate material of the HIL, or it may be a dopant. Using a doped HIL allows for selection of dopants for their electrical properties and for selection of the host for morphological properties such as ease of deposition, wetting, flexibility, and toughness. Preferred properties of the HIL material enable efficient hole injection from the anode into the HIL material. The charge-bearing component of HIL 120 preferably has an IP not exceeding approximately 0.5 eV above the IP of the anode material. Similar conditions apply to any layer into which holes are injected. Another difference between HIL materials and conventional hole transport materials typically used in hole transport layers for OLEDs, QLEDs, or PeLEDs is that the hole conductivity of such HIL materials can be substantially lower than that of conventional hole transport materials. The thickness of the HIL 120 of the present invention can be thick enough to planarize the anode and enable efficient hole injection, but thin enough not to impede hole transport. For example, a HIL thickness as low as 10 nm is acceptable. However, for some devices, a HIL thickness of up to 50 nm may be preferred.

[0121] In apparatus 100, the electron injection layer 150 can be any layer that improves electron injection from cathode 155 to electron transport layer 145. Examples of materials that can be used as the electron injection layer are inorganic salts such as lithium fluoride (LiF), sodium fluoride (NaF), barium fluoride (BaF), cesium fluoride (CsF), and cesium carbonate (CsCO3). Other examples of materials that can be used as the electron injection layer are metal oxides such as zinc oxide (ZnO) and titanium dioxide (TiO2), as well as metals such as calcium (Ca), barium (Ba), magnesium (Mg), and ytterbium (Yb). Other materials or combinations of materials can be used for the injection layer. Depending on the configuration of the particular apparatus, the injection layer may be located at a position different from that shown in apparatus 100.

[0122] Devices manufactured according to embodiments of the present invention may optionally include a barrier layer 160. One purpose of the barrier layer 160 is to protect the device layers from environmental contaminants, including moisture, vapor, and / or gases. Optionally, the barrier layer 160 may be deposited above, below, or beside any other portion of the substrate, electrode, or device, including its edges. Optionally, the barrier layer 160 may be a bulk material such as glass or metal, and this bulk material may be fixed above, below, or beside any other portion of the substrate, electrode, or device. Optionally, the barrier layer 160 may be deposited on a membrane, and this membrane may be fixed above, below, or beside any other portion of the substrate, electrode, or device. When the barrier layer 160 is deposited on a membrane, preferred membrane materials include glass, plastics such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), and metal foil. When the barrier layer 160 is a bulk material or deposited on a membrane, the preferred materials for securing the membrane or bulk material to the device include thermal adhesives or UV-curable adhesives, hot melt adhesives, and pressure-sensitive adhesives.

[0123] The barrier layer 160 may be a bulk material or may be formed using various known deposition techniques, including sputtering, vacuum thermal evaporation, electron beam deposition, and chemical vapor deposition (CVD) techniques such as plasma-enhanced chemical vapor deposition (PECVD) and atomic layer deposition (ALD). The barrier layer 160 may comprise compositions having a single phase or compositions having multiple phases. Any suitable material or combination of materials may be used for the barrier layer 160. The barrier layer 160 may incorporate organic or inorganic compounds, or both. Preferred inorganic barrier layer materials include: alumina, such as Al₂O₃; silicon oxide, such as SiO₂; and silicon nitride, such as SiN. x ; and bulk materials, such as glass and metal. Preferred organic barrier layer materials comprise polymers. Barrier layer 160 may comprise a single layer or multiple layers. Multilayer barriers comprising one or more barrier materials in one or more layers may be preferred for certain devices. For example, in multilayer barriers of SiN... x / polymer / SiN x In this context, a preferred example of a multilayer barrier is one that includes SiN. x A barrier consisting of alternating layers of polymer.

[0124] Figure 6A stacked light-emitting device 600 with two emitting units is shown. The light-emitting device 600 may include one or more OLED, QLED, or PeLED emitting units or combinations thereof. The device 600 may include a first electrode 610, a first emitting unit 620, a first charge-generating layer 630, a second emitting unit 640, and a second electrode 650. The first electrode 610 may be directly connected to an external power supply E1. The second electrode 650 may be directly connected to an external power supply E2. The first charge-generating layer 630 may be directly connected to an external power supply E3. The device 600 is fabricated by sequentially depositing the described layers.

[0125] Figure 8 A layer structure of a stacked light-emitting device 800 with two emitting units is depicted. The light-emitting device 800 may include one or more OLED, QLED, or PeLED emitting units or combinations thereof. The device 800 may include a substrate 805, an anode 810, a first hole injection layer 815, a first hole transport layer 820, a first emitting layer 825, a first hole blocking layer 830, a first electron transport layer 835, a first charge generation layer 840, a second hole injection layer 845, a second hole transport layer 850, a second emitting layer 855, a second hole blocking layer 860, a second electron transport layer 865, a first electron injection layer 870, and a cathode 875. The first emitting unit 880 may include the first hole injection layer 815, the first hole transport layer 820, the first emitting layer 825, the first hole blocking layer 830, and the first electron transport layer 835. The second emission unit 885 may include a second hole injection layer 845, a second hole transport layer 850, a second emission layer 855, a second hole blocking layer 860, a second electron transport layer 865, and a first electron injection layer 870. The device 800 may be manufactured by sequentially depositing the described layers.

[0126] Figure 7 A stacked light-emitting device 700 with three emitting units is shown. The light-emitting device 700 may include one or more OLED, QLED, or PeLED emitting units or combinations thereof. The device 700 may include a first electrode 710, a first emitting unit 720, a first charge-generating layer 730, a second emitting unit 740, a second charge-generating layer 750, a third emitting unit 760, and a second electrode 770. The first electrode 710 may be directly connected to an external power supply E1. The second electrode 770 may be directly connected to an external power supply E2. The first charge-generating layer 730 may be directly connected to an external power supply E3. The second charge-generating layer 750 may be connected to an external power supply E4. The device 700 may be manufactured by sequentially depositing the described layers.

[0127] Figure 9A layer structure of a stacked light-emitting device 900 having three emitting units is depicted. The light-emitting device 900 may include one or more OLED, QLED, or PeLED emitting units or combinations thereof. The device 900 may include a substrate 905, an anode 910, a first hole injection layer 915, a first hole transport layer 920, a first emitting layer 925, a first electron transport layer 930, a first charge generation layer 935, a second hole transport layer 940, a second emitting layer 945, a second electron transport layer 950, a second charge generation layer 955, a third hole transport layer 960, a third emitting layer 965, a third electron transport layer 970, a first electron injection layer 975, and a cathode 980. The first emitting unit 985 may include the first hole injection layer 915, the first hole transport layer 920, the first emitting layer 925, and the first electron transport layer 930. The second emitting unit 990 may include the second hole transport layer 940, the second emitting layer 945, and the second electron transport layer 950. The third emission unit 995 may include a third hole transport layer 960, a third emission layer 965, a third electron transport layer 970, and a first electron injection layer 975. The device 900 may be manufactured by sequentially depositing the described layers.

[0128] Figure 8 and Figure 9 The simple layered structure shown is provided by way of non-limiting example, and it should be understood that embodiments of the invention can be used in combination with a variety of other structures. The specific materials and structures described are exemplary in nature, and other materials and structures can be used. Functional light-emitting devices can be realized by combining the described layers in different ways, or layers can be omitted entirely, depending on factors such as performance, design, and cost. Other layers not specifically described may also be included. Materials other than those specifically described may be used. Although many examples provided herein describe the layers as comprising a single material, it should be understood that combinations of materials can be used. Moreover, layers may have sublayers. The names given to the layers herein are not intended to be strictly limiting. For example, in a device, an electron transport layer can transport electrons to an emission layer and also block holes from exiting the emission layer, and can be described as an electron transport layer or a hole blocking layer.

[0129] like Figure 6 , Figure 7 , Figure 8 and Figure 9The stacked light-emitting device architecture described herein offers one or more of the following advantages: (1) light from multiple emitting units can be combined in the same surface area of ​​the device, thereby increasing the brightness of the device; (2) multiple emitting units can be electrically connected in series, with substantially the same current passing through each emitting unit, thereby allowing the device to operate with increased brightness without a significant increase in current density, thereby extending the operating life of the device; and (3) light emitted from individual emitting units can be controlled individually, thereby allowing the brightness and / or color of the device to be tuned according to the exact needs of the application.

[0130] Typically, the operating lifetime (LT) of OLED, QLED, or PeLED at a certain brightness (L) can be expressed as LT2 = LT1 × (L1 / L2). AF , where LT1 is the lifetime measured at (high) luminance L1, LT2 is the predicted lifetime at (low) luminance L2, and AF is the acceleration factor. For OLED, QLED, and PeLED, an approximate acceleration factor for converting the measured lifetime at higher luminance to the predicted lifetime at lower luminance has been determined to be in the range of approximately 1.5–2.0.

[0131] For a stacked light-emitting device comprising two emitting units, for the same total device luminance, each emitting unit can operate at a luminance L2 that is twice the luminance L1 required by an equivalent light-emitting device with a single emitting unit. Assuming an acceleration factor of 2.0, the expected operating lifetime of the stacked light-emitting device with two emitting units is twice the expected operating lifetime of the equivalent light-emitting device with a single emitting unit. 2 =4 times. Furthermore, for a stacked light-emitting device comprising three emitting units, for the same total device luminance, each emitting unit can operate at a luminance L2 that is three times lower than the luminance L1 required by an equivalent light-emitting device with a single emitting unit. Assuming an acceleration factor of 2.0, the expected operating lifetime of the stacked light-emitting device with three emitting units is 3 times the expected operating lifetime of the equivalent light-emitting device with a single emitting unit. 2 =9 times.

[0132] Examples of stacked light-emitting devices containing organic light-emitting materials are found in U.S. Patent US 5707745 B1, Forrest et al. Described in Forrest et al. and Jung et al. All such citations are incorporated herein by reference in their entirety. U.S. Patent US 5,707,745 B1 describes a multicolor stacked organic light-emitting device. Forrest et al. and Jung et al. described a stacked organic light-emitting device comprising independently addressable red, green, and blue emitting units. Jung et al. described a top-emission stacked organic light-emitting device comprising three emitting units, wherein light from the three emitting units can be combined to produce white light emitted from the device.

[0133] The performance advantages of such stacked light-emitting devices are well known. However, to date, no stacked blue OLED, QLED, or PeLED device comprising two or more emitting units that emit blue light with substantially different chromaticities has been demonstrated. Therefore, the novel device architecture presented herein differs from and surpasses existing state-of-the-art technologies.

[0134] This invention relates to a stacked blue light emitting device architecture comprising two or more emitting units that emit blue light with substantially different chromaticities for use in displays, lighting panels, and other optoelectronic devices. Optionally, at least one emitting unit may emit a deeper blue light, and at least one emitting unit may emit a lighter blue light. Optionally, the emitting units may be independently addressable and may emit light independently of each other. Optionally, the emitting units may be jointly addressable and may not emit light independently of each other.

[0135] Such stacked blue light emitting devices can be incorporated into the red, green, and blue subpixels of an OLED display. When the blue subpixels of such a display are required to emit relatively saturated blue light, the emitting units emitting deeper blue light can be addressed individually and can emit light to generate the displayed image, while the emitting units emitting lighter blue light can remain inactive. However, when only the blue subpixels of such a display are required to emit relatively unsaturated blue light, the emitting units emitting lighter blue light can be addressed individually and can emit light to generate the displayed image, while the emitting units emitting deeper blue light can remain inactive. Light can be emitted from the relatively more efficient and / or more stable lighter blue emitting units to render most of the displayed image, while light emitted from the relatively less efficient and / or less stable darker blue emitting units only needs to render a small portion of the image. This can thus improve the efficiency and / or lifespan of the display. Furthermore, the lighter blue emitting units can be used alone or in combination with the darker blue emitting units to provide light to the red and green color conversion layers in the red and green subpixels.

[0136] Optionally, an apparatus manufactured according to an embodiment of the present invention may include two emission layers. Optionally, an apparatus manufactured according to an embodiment of the present invention may include three emission layers. Optionally, an apparatus manufactured according to an embodiment of the present invention may include four or more emission layers.

[0137] Optionally, an apparatus manufactured according to an embodiment of the present invention may include two transmitting units. Optionally, an apparatus manufactured according to an embodiment of the present invention may include three transmitting units. Optionally, an apparatus manufactured according to an embodiment of the present invention may include four or more transmitting units.

[0138] Optionally, the transmitting unit may include an transmitting layer. Optionally, the transmitting unit may further include one or more additional layers, such as a hole injection layer, a hole transport layer, an electron blocking layer, a hole blocking layer, an electron transport layer, and / or an electron injection layer. Optionally, the transmitting unit may include some of these additional layers, and may exclude some of these additional layers.

[0139] An apparatus manufactured according to an embodiment of the invention may optionally include one or more charge-generating layers. Optionally, the charge-generating layers may be used to separate two or more emitting units within a stacked light-emitting device. Figure 6 The stacked light-emitting device 600 depicted includes a first charge-generating layer 630 that separates a first emitting unit 620 from a second emitting unit 640. Figure 7 The stacked light-emitting device 700 depicted includes a first charge-generating layer 730 that separates a first emitting unit 720 from a second emitting unit 740. Figure 7 The stacked light-emitting device 700 depicted also includes a second charge-generating layer 750 that separates the second emitting unit 740 from the third emitting unit 760.

[0140] The charge generation layer 630, 730, or 750 may comprise a single layer or multiple layers. Optionally, the charge generation layer 630, 730, or 750 may comprise an n-doped layer for electron injection and a p-doped layer for hole injection. Optionally, the charge generation layer 630, 730, or 750 may comprise a hole injection layer (HIL). Optionally, the p-doped layer of the charge generation layer 630, 730, or 750 may serve as the hole injection layer (HIL). Figure 9 A stacked light-emitting device 900 with three emitting units is depicted, wherein a first charge-generating layer 935 includes a hole injection layer (not shown), and a second charge-generating layer 955 includes a hole injection layer (not shown). Optionally, the charge-generating layers 630, 730, or 750 may be positioned adjacent to and in contact with a separate hole injection layer. Figure 8 A stacked light-emitting device 800 with two emitting units is depicted, wherein a first charge-generating layer 840 is adjacent to and in contact with a second hole-injecting layer 845.

[0141] Optionally, the charge generation layer 630, 730, or 750 may include an electron injection layer (EIL). Optionally, an n-doped layer of the charge generation layer 630, 730, or 750 may serve as an electron injection layer (EIL). Figure 9 A stacked light-emitting device 900 with three emitting units is depicted, wherein a first charge-generating layer 935 includes an electron injection layer (not shown), and a second charge-generating layer 955 includes an electron injection layer (not shown). Optionally, charge-generating layers 630, 730, or 750 may be positioned adjacent to and in contact with individual electron injection layers.

[0142] Optionally, charge generation layers 630, 730, or 750 may include layers for conducting holes and / or injecting them into the layers of the device. Such layers may comprise any suitable material or combination of materials known in the art, enabling the layer to conduct holes and / or inject them into the layers of the device. Such layers may be referred to as anode layers. Optionally, charge generation layers 630, 730, or 750 may include layers for conducting electrons and / or injecting them into the layers of the device. Such layers may comprise any suitable material or combination of materials known in the art, enabling the layer to conduct electrons and / or inject them into the layers of the device. Such layers may be referred to as cathode layers. Optionally, charge generation layers 630, 730, or 750 may include anode and cathode layers electrically connected to each other.

[0143] The charge generation layer 630, 730, or 750 can be deposited using a solution process or a vacuum deposition process. The charge generation layer 630, 730, or 750 can be made of any suitable material that enables the injection of electrons and holes. The charge generation layer 630, 730, or 750 can be doped or undoped. Doping can be used to enhance conductivity.

[0144] An example of a charge generation layer in a vapor process is a bilayer structure consisting of lithium-doped BPhen (Li-BPhen) as the n-doped layer for electron injection and 1,4,5,8,9,11-hexaazabenzophenanthrene (HATCN) as the p-doped layer for hole injection. An example of a charge generation layer in a solution process is a bilayer structure consisting of polyethyleneimine (PEI) surface-modified zinc oxide (ZnO) as the n-doped layer for electron injection and molybdenum oxide (MoO3) or tungsten trioxide (WO3) as the p-doped layer for hole injection. Other materials or combinations of materials can be used for the charge generation layer. Depending on the configuration of a particular apparatus, the charge generation layer may be positioned at a location different from the positions shown in apparatus 800 and apparatus 900.

[0145] Optionally, one or more charge-generating layers within the stacked light-emitting device may be directly connected to one or more external power sources. Optionally, one or more emitting units of the stacked light-emitting device may be independently addressable and capable of emitting light independently of each other. The advantage of connecting one or more charge-generating layers to one or more external power sources is that the light emission of individual emitting units of the stacked light-emitting device can be selected and controlled individually according to the needs of the application. In this invention, connecting one or more charge-generating layers to one or more external power sources allows control over the chromaticity of the blue light from the stacked light-emitting device.

[0146] Unless otherwise stated, any layer in the various embodiments can be deposited by any suitable method. Methods include vacuum thermal evaporation, sputtering, electron beam physical vapor deposition, organic vapor deposition, and organic vapor jet printing. Other suitable methods include spin coating and other solution-based processes. Substantially similar processes can be used to deposit materials used in OLED, QLED, and PeLED devices, which facilitates the combination of these materials in the light-emitting device.

[0147] The device manufactured according to embodiments of the present invention can be incorporated into a wide range of consumer products. Optionally, the device can be used in displays for televisions, computer monitors, tablet computers, laptop computers, smartphones, mobile phones, digital cameras, video recorders, smartwatches, fitness trackers, personal digital assistants, vehicle displays, and other electronic devices. Optionally, the device can be used in miniature displays or head-up displays. Optionally, the device can be used in lighting panels for internal or external lighting and / or signal transmission in smart packaging or billboards.

[0148] Optionally, various control mechanisms can be used to control the light-emitting device manufactured according to the present invention, including passive matrix and active matrix addressing schemes.

[0149] The materials and structures described herein can be applied to devices other than light-emitting devices. For example, these materials and structures can be used in other optoelectronic devices such as solar cells, photodetectors, transistors, or lasers.

[0150] The present invention relates to a novel light-emitting device architecture for use in devices such as displays, lighting panels and other optoelectronic devices, and more particularly to a stacked blue light emitting device comprising two or more emitting units that emit blue light having substantially different chromaticities.

[0151] This invention provides an apparatus. This apparatus is described in reference to... Figure 6To understand this from the arrangement 600, the figure depicts an exemplary stacked light-emitting device with two emitting units. In one embodiment, the device includes a stacked blue light emitting device 600, comprising: a first electrode 610; a second electrode 650; a first emitting unit 620 including a first emitting layer (not shown); a second emitting unit 640 including a second emitting layer (not shown); and a first charge generating layer 630; wherein the first emitting unit 620, the second emitting unit 640, and the first charge generating layer 630 are all disposed between the first electrode 610 and the second electrode 650; the first emitting unit 620 is disposed above the first electrode 610; the first charge generating layer 630 is disposed above the first emitting unit 620; the second emitting unit 640 is disposed above the first charge generating layer 630; and the second electrode 650 is disposed above the second emitting unit 640; the first emitting unit 620 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm, the peak wavelength being defined as a first peak wavelength; the first emitting unit 620 emits a first CIE... The first emission layer emits blue light with chromaticity coordinates (x1, y1) in the CIE 1931(x,y) color space; the second emission unit 640 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm, which is defined as the second peak wavelength; the second emission unit 640 emits blue light with a second chromaticity, the second chromaticity having chromaticity coordinates (x2, y2) in the second CIE 1931(x,y) color space; the second chromaticity is substantially different from the first chromaticity; and the first emission layer and the second emission layer include organic light-emitting materials, quantum dot light-emitting materials and / or perovskite light-emitting materials.

[0152] As used herein, “red,” “green,” and “blue” refer to the degree to which light emitted by a luminescent material, emitting layer, emitting unit, region, or device can be described as similar to or different from the hue of red, green, and blue, respectively. Materials, layers, regions, units, and devices may be described herein with reference to the hue of the light they emit. As used herein, a red material, layer, region, unit, or device is one that emits light with a red hue having an emission spectrum in the visible spectrum with a peak wavelength in the range of 580 nm to 780 nm; a green material, layer, region, unit, or device is one that emits light with a green hue having an emission spectrum in the visible spectrum with a peak wavelength in the range of 500 nm to 580 nm; and a blue material, layer, region, unit, or device is one that emits light with a blue hue having an emission spectrum in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm.

[0153] Similarly, any reference to a color-changing layer refers to a layer that converts or modifies light of another hue to have a wavelength as specified for that hue. Generally, there are two categories of color-changing layers: color filters that modify the spectrum by removing unwanted wavelengths of light, and color conversion layers that convert higher-energy photons into lower-energy photons. A red color filter is a filter that produces light with an emission spectrum having a peak wavelength in the range of 580 nm to 780 nm. A green color filter is a filter that produces light with an emission spectrum having a peak wavelength in the range of 500 nm to 580 nm. A blue color filter is a filter that produces light with an emission spectrum having a peak wavelength in the range of 380 nm to 500 nm. A red color conversion layer is a conversion layer that produces light with an emission spectrum having a peak wavelength in the range of 580 nm to 780 nm. A green color conversion layer is a conversion layer that produces light with an emission spectrum having a peak wavelength in the range of 500 nm to 580 nm. Figure 19 An arrangement 1900 for an exemplary RGBW OLED display is depicted, which includes a red color filter 1985, a green color filter 1990, and a blue color filter 1995 that modify the white spectrum. Figure 20 An arrangement 2000 for an exemplary QD-OLED display is depicted, comprising a red color conversion layer 2050 and a green color conversion layer 2060 that convert photons of blue light into photons of red and green light.

[0154] As used herein, light emitted from a material, layer, unit, region, or device may be referred to herein as “deep” or “relatively deep” or “shallow” or “relatively light,” referring to the relative saturation of the light. In one embodiment, as used herein, “deep blue” light refers to blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm, and “light blue” light refers to blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm. In one embodiment, as used herein, “relatively deep” blue light refers to blue light with a relatively short peak wavelength, and “relatively light” blue light refers to blue light with a relatively long peak wavelength.

[0155] Chromaticity refers to the objective specification of color quality, and is independent of its luminance. As used in this article, the “chromaticity” of light can be visualized and quantified using a CIE 1931(x,y) chromaticity diagram depicting the CIE 1931XYZ color space. The chromaticity of light emitted from a material, layer, unit, region, or device can be quantified by its CIE 1931(x,y) coordinates on the CIE 1931(x,y) chromaticity diagram.

[0156] As used herein, if the light emitted from a material, layer, unit, region, or device is distinctly different to the average human eye, then the emitted light can be considered to have "substantially different" chromaticity. As used herein, if the light emitted from a material, layer, unit, region, or device is indistinguishable to the average human eye, then the emitted light can be considered to have "substantially identical" chromaticity.

[0157] A suitable technique for quantizing the chromaticity and chromatic difference of light is to use the McAdam ellipse. (See also...) Figure 13 To visualize this, the diagram depicts the McAdam ellipse superimposed on the CIE 1931(x,y) color space chromaticity diagram. Within the CIE 1931(x,y) color space chromaticity diagram, a first-order McAdam ellipse contains all chromaticity coordinates that are indistinguishable to the average human eye from those at the ellipse's center. In other words, to the average human eye, any light whose chromaticity coordinates are outside the first-order ellipse will appear chromaticly distinct from that at the ellipse's center. Tolerances can be introduced by extending the ellipse. For example, the axis of a second-order McAdam ellipse is twice the size of that of a first-order ellipse, and the axis of a tenth-order McAdam ellipse is ten times the size of that of a first-order ellipse. Figure 13 All the McAdam ellipses depicted are tenth-order McAdam ellipses.

[0158] In one embodiment, the second chromaticity coordinates (x2, y2) measured for light emitted from the second emitting unit 640 are not contained within a first-order McAdam ellipse centered on the first chromaticity coordinates (x1, y1) measured for light emitted from the first emitting unit 620. In another embodiment, the second chromaticity coordinates (x2, y2) measured for light emitted from the second emitting unit 640 are not contained within a third-order McAdam ellipse centered on the first chromaticity coordinates (x1, y1) measured for light emitted from the first emitting unit 620.

[0159] Another suitable technique for characterizing the chromaticity difference of light emitted from a material, layer, unit cell, region, or device is to quantify the absolute difference in the CIE 1976 (u',v') chromaticity coordinates. The CIE 1976 (u',v') color space is preferred over the CIE 1931 (x,y) color space because, unlike the CIE 1931 (x,y) color space, in the CIE 1976 (u',v') color space, distance is approximately proportional to the perceived color difference. The conversion between color spaces is very straightforward: u′=4x / (-2x+12y+3) and v′=9y / (-2x+12y+3). The chromaticity difference can be quantized as: Δuv=√(Δu′) 2 +Δv′ 2 )=√((u1–u2) 2 +(v1–v2) 2Δuv is the distance between the first chromaticity coordinates (u1, v1) and the second chromaticity coordinates (u2, v2) in the CIE 1976 (u′, v′) color space. As used herein, if the chromaticity difference defined by Δuv is 0.010 or greater, light emitted from a first material, region, unit, or device having the first chromaticity coordinates (u1, v1) can be considered to have a substantially different chromaticity than light emitted from a second material, region, unit, or device having the second chromaticity coordinates (u2, v2). In one embodiment, the chromaticity coordinates (x1, y1) of the first CIE 1931 (x, y) color space can be converted to chromaticity coordinates (u1, v1) of the CIE 1976 (u', v') color space; and the chromaticity coordinates (x2, y2) of the second CIE 1931 (x, y) color space can be converted to chromaticity coordinates (u2, v2) of the second CIE 1976 (u', v') color space; wherein the first chromaticity coordinates (u1, v1) of the light emitted from the first blue emitting layer 620 and the second chromaticity coordinates (u2, v2) of the light emitted from the second blue emitting layer 640 are sufficiently different such that the chromaticity difference defined by Δuv is 0.010 or greater.

[0160] Another suitable technique for characterizing the chromaticity difference of light emitted from a material, layer, unit, region, or device is to measure the emission spectrum and compare the peak emission wavelengths. In one embodiment, the second peak wavelength of light emitted from the second emitting unit 640 is at least 4 nm larger or at least 4 nm smaller than the first peak wavelength of light emitted from the first emitting unit 620.

[0161] The proposed novel device architecture is ideally suited for OLED, QLED, and PeLED displays. The advantages of incorporating one or more organic light-emitting materials, quantum dot light-emitting materials, and / or perovskite light-emitting materials in the first emission layer of the first emission unit 620 and the second emission layer of the second emission unit 640 of the stacked blue light-emitting device can be found in Table 1 and... Figure 12 The data shown in Table 1 is used to illustrate this. Figure 12 The data can also be used to demonstrate the advantages of combining one or more emitting layers, including different types of luminescent materials, in a stacked blue light emitting device.

[0162] Table 1 shows the CIE 1931 (x,y) color coordinates for single-emitting-unit blue OLED, QLED, and PeLED devices. Table 1 also includes CIE 1931 (x,y) color coordinates for the DCI-P3 and Rec.2020 color gamut standards and for commercial OLED displays. Generally, for blue light, a lower CIE y value corresponds to a darker emission. This can be referenced... Figure 12To understand this, the figure depicts data from Table 1 for light blue OLED (square), dark blue OLED (pentagonal), dark blue QLED (triangular), and dark blue PeLED (circular), as well as data for commercial OLED displays (star-shaped). Figure 12 The DCI-P3 color gamut in a and Figure 12 The primary color data for the Rec.2020 color gamut in b.

[0163]

[0164] Table 1: Examples of single-emitting-unit blue OLEDs, QLEDs, and PeLEDs, and examples of commercial OLED displays. CIE 1931 (x,y) color coordinates. Also includes color coordinates for the DCI-P3 and Rec.2020 color gamut standards. .

[0165] The CIE 1931 (x,y) color coordinate data reported in Table 1 for single-emitting-unit blue OLED, QLED, and PeLED devices are exemplary. Commercial OLED data was extracted from an Apple iPhone X that fully supports the DCI-P3 color gamut. This dataset is available from Raymond Soneira of DisplayMate Technologies Corporation (Soneira et al.). Other data are taken from peer-reviewed selections of scientific journals: light blue OLED data from Zaoni et al.; dark blue OLED data from Takita et al.; dark blue QLED data from Wang et al.; and dark blue PeLED data from Kumar et al. Data from these sources are used as examples and should be considered non-limiting. Data from other peer-reviewed scientific journals, simulation data collected from laboratory devices, and / or experimental data may also be used to demonstrate the aforementioned advantages of the claimed device architecture.

[0166] The emission spectrum can be used to further understand the presented colorimetric data. Figure 14 Exemplary normalized electroluminescence emission spectra of single-emitting-unit blue OLEDs summarized in Table 1 are depicted. Spectra depicted using dashed lines correspond to the spectra of OLEDs emitting light blue light with an emission peak at 470 nm. Spectra depicted using solid lines correspond to the spectra of OLEDs emitting deep blue light with an emission peak at 451 nm. Note that the shape of the emission spectra has been simplified to bell curves for ease of understanding. Figure 14 The example used OLED, but the same principle can also be applied to QLED and PeLED.

[0167] The emission spectrum of the peak located closer to the luminous efficacy function at 555 nm usually has greater overlap with the luminous efficacy function. Figure 14The results show that the light blue emission spectrum overlaps more significantly with the photoluminescence efficiency function compared to the corresponding dark blue emission spectrum. This means that for the same perceived brightness, light blue light requires less image quality than dark blue light. Therefore, an emitting unit emitting light blue light can thus have higher efficiency than an emitting unit emitting dark blue light.

[0168] Therefore, the stacked blue light emitting device of the present invention, comprising lighter and darker blue emitting units having substantially different chromaticities, enables devices (such as displays) to operate with improved efficiency. This is because the more efficient lighter blue emitting units can be used to render most images, while the less efficient darker blue emitting units are only used to render a small number of images in which an expanded color gamut is required. This saves significant energy, as most images rendered by displays in everyday use do not require an expanded color gamut.

[0169] To demonstrate such a stacked blue light emitting device, it is required that two or more emitting units be independently addressable, allowing them to emit light independently of each other. In one embodiment, the first emitting unit 620 and the second emitting unit 640 are independently addressable and can emit light independently of each other. Figure 6 As depicted, this can be achieved if one or more charge-generating layers 630 are directly connected to an external power source.

[0170] In one implementation scheme, such as Figure 6 As depicted in arrangement 600, the first electrode 610 is directly connected to an external power supply E1, the second electrode 650 is directly connected to an external power supply E2, and the first charge generation layer 630 is directly connected to an external power supply E3. The first transmitting unit is independently addressable; for a standard device architecture, E1 is placed at a positive potential relative to E3, or for an inverted device architecture, E1 is placed at a negative potential relative to E3. The second transmitting unit is independently addressable; for a standard device architecture, E3 is placed at a positive potential relative to E2, or for an inverted device architecture, E3 is placed at a negative potential relative to E2.

[0171] In one embodiment, the device includes a stacked blue light emitting device comprising at least two emitting units. Figure 15Various configurations of the emitting units of a stacked blue light emitting device with two blue emitting units are depicted. In each configuration, the stacked blue light emitting device includes a first electrode 610, a first blue emitting unit 620 (which includes a first blue emitting layer (not shown)), a first charge generating layer 630, a second blue emitting unit 640 (which includes a second blue emitting layer (not shown)), and a second electrode 650. The first blue emitting unit 620, the first charge generating layer 630, and the second blue emitting unit 640 are all disposed between the first electrode 610 and the second electrode 650. The first blue emitting unit 620 is disposed above the first electrode 610. The first charge generating layer 630 is disposed above the first blue emitting unit 620. The second blue emitting unit 640 is disposed above the first charge generating layer 630. The second electrode 650 is disposed above the second blue emitting unit 640. In each configuration, the first blue emitting layer and the second blue emitting layer each include an organic light-emitting material, a quantum dot light-emitting material, and / or a perovskite light-emitting material.

[0172] In one embodiment, the first blue emitting unit 620 is capable of emitting blue light and the second blue emitting unit 640 is capable of emitting blue light. In one embodiment, both the first blue emitting unit 620 and the second blue emitting unit 640 can emit blue light in the visible spectrum with peak wavelengths in the range of 380 nm to 500 nm. In one embodiment, as... Figure 15 As depicted in device 1510, the first blue emitting unit 620 emits a lighter blue light and the second blue emitting unit 640 emits a darker blue light. In one embodiment, as... Figure 15 As depicted in device 1520 in b, the first blue emitting unit 620 can emit a deeper blue light and the second blue emitting unit 640 can emit a lighter blue light.

[0173] In one embodiment, the first blue emitting unit 620 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm; and the second blue emitting unit 640 emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm. In one embodiment, the first blue emitting unit 620 emits blue light with a CIE 1931y coordinate of 0.080 or less; and the second blue emitting unit 640 emits blue light with a CIE 1931y coordinate greater than 0.080. In one embodiment, the second blue emitting unit 640 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm; and the first blue emitting unit 620 emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm. In one embodiment, the second blue emitting unit 640 emits blue light with a CIE 1931y coordinate of 0.080 or less; and the first blue emitting unit 620 emits blue light with a CIE 1931y coordinate greater than 0.080.

[0174] Such exemplary embodiments can be implemented using any suitable combination of luminescent materials from the light blue OLED device, dark blue OLED device, dark blue QLED device and / or dark blue PeLED device described in Table 1.

[0175] In one implementation, the first transmitting unit 620 and the second transmitting unit 640 are co-addressable and can transmit light without being independent of each other.

[0176] The inherent properties of organic light-emitting materials, quantum dot light-emitting materials, and perovskite light-emitting materials make them well-suited for the stacked blue light emitting device architecture disclosed herein. These properties include easily tunable optical band gaps in the visible, ultraviolet, and infrared spectra, high color saturation enabling the display to have a wide color gamut, excellent charge transport characteristics, and low non-emissivity.

[0177] In one preferred embodiment, the first and second blue emitting layers comprise organic light-emitting materials. In one embodiment, the first and second blue emitting layers comprise fluorescent organic light-emitting materials. In one embodiment, the first and second blue emitting layers comprise phosphorescent organic light-emitting materials.

[0178] In one embodiment, at least one of the first and second emitting layers comprises a phosphorescent organic light-emitting material; and at least one of the first and second emitting layers comprises a fluorescent organic light-emitting material. In a preferred embodiment, the first blue emitting layer is a light blue emitting layer comprising a phosphorescent organic light-emitting material; and the second blue emitting layer is a dark blue emitting layer comprising a fluorescent organic light-emitting material. In another preferred embodiment, the first blue emitting layer is a dark blue emitting layer comprising a fluorescent organic light-emitting material; and the second blue emitting layer is a light blue emitting layer comprising a phosphorescent organic light-emitting material. Such a stacked blue light emitting device architecture can be advantageous because the more efficient but less stable phosphorescent organic material can emit light blue light to render a light blue color, while the less efficient but more stable fluorescent organic material can emit dark blue light to render a dark blue color.

[0179] In one embodiment, the first and second blue emitting layers comprise quantum dot luminescent materials. In another embodiment, the first and second blue emitting layers comprise perovskite luminescent materials.

[0180] In one embodiment, the first blue emitting layer comprises a first type of blue luminescent material, which is an organic luminescent material, a quantum dot luminescent material, or a perovskite luminescent material; and the second blue emitting layer comprises a second type of blue luminescent material, which is also an organic luminescent material, a quantum dot luminescent material, or a perovskite luminescent material; wherein the second type of blue luminescent material is different from the first type of blue luminescent material. In a preferred embodiment, the first blue emitting layer comprises an organic luminescent material, and the second blue emitting layer comprises a quantum dot luminescent material or a perovskite luminescent material.

[0181] In one embodiment, a stacked light-emitting device capable of rendering the blue primary color of the DCI-P3 or Rec.2020 color gamut can be demonstrated by combining a first blue emitting unit 620 containing organic light-emitting material with a second blue emitting unit 640 containing organic light-emitting material. In another embodiment, a stacked blue light emitting device capable of rendering the blue primary color of the DCI-P3 or Rec.2020 color gamut can be demonstrated by combining a first emitting unit 620 containing organic light-emitting material with a second emitting unit 640 containing quantum dot light-emitting material or perovskite light-emitting material. The advantage of such devices is that, when implemented in one or more sub-pixels of a display, the display can render a wider range of colors experienced in everyday life, thereby improving functionality and user experience. Further advantages of such devices include providing additional benefits to the display, such as increased efficiency, higher brightness, improved operating life, lower voltage, and / or reduced cost.

[0182] In one embodiment, the first blue emitting unit 620 includes one and more emitting layers. In one embodiment, the first blue emitting unit 620 includes two or more emitting layers. In one embodiment, the second blue emitting unit 640 includes one and more emitting layers. In one embodiment, the second blue emitting unit 640 includes two or more emitting layers. In one embodiment, the first emitting layer includes one and more luminescent materials. In one embodiment, the first emitting layer includes two or more luminescent materials. In one embodiment, the second emitting layer includes one and more luminescent materials. In one embodiment, the second emitting layer includes two or more luminescent materials.

[0183] This invention may be referenced Figure 7 To further understand this, the figure depicts an exemplary stacked light-emitting device with three emitting units, as shown in arrangement 700. In one embodiment, the device includes a stacked blue light emitting device 700, comprising: a first electrode 710; a second electrode 770; a first emitting unit 720 including a first emitting layer (not shown); a second emitting unit 740 including a second emitting layer (not shown); and a first charge generating layer 730; wherein the first emitting unit 720, the second emitting unit 740, and the first charge generating layer 730 are all disposed between the first electrode 710 and the second electrode 770; the first emitting unit 720 is disposed above the first electrode 710; the first charge generating layer 730 is disposed above the first emitting unit 720; the second emitting unit 740 is disposed above the first charge generating layer 730; and the second electrode 770 is disposed above the second emitting unit 740; the first emitting unit 720 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm, the peak wavelength being defined as a first peak wavelength; the first emitting unit 720 emits a first CIE... The first emission layer emits blue light with chromaticity coordinates (x1, y1) in the CIE 1931(x,y) color space; the second emission unit 740 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm, which is defined as the second peak wavelength; the second emission unit 740 emits blue light with a second chromaticity, the second chromaticity having chromaticity coordinates (x2, y2) in the second CIE 1931(x,y) color space; the second chromaticity is substantially different from the first chromaticity; and the first emission layer and the second emission layer include organic light-emitting materials, quantum dot light-emitting materials and / or perovskite light-emitting materials.

[0184] The stacked blue light emitting device 700 further includes: a third emitting unit 760, which includes a third emitting layer (not shown); and a second charge generating layer 750; wherein the third emitting unit 760 and the second charge generating layer 750 are disposed between the second emitting unit 740 and the second electrode 770; the second charge generating layer 750 is disposed above the second emitting unit 740; the third emitting unit 760 is disposed above the second charge generating layer 750; the second electrode 770 is disposed above the third emitting unit 760; the third emitting unit 760 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm, the peak wavelength being defined as the third peak wavelength; the third emitting unit 760 emits blue light with chromaticity coordinates (x3, y3) in the first CIE 1931 (x, y) color space; and the third emitting layer includes an organic light-emitting material, a quantum dot light-emitting material, or a perovskite light-emitting material.

[0185] Figure 16 Various configurations of the blue emitting units in a stacked blue light emitting device with three blue emitting units are depicted. In each configuration, the stacked blue light emitting device includes a first electrode 710, a first blue emitting unit 720 (which includes a first blue emitting layer (not shown)), a first charge generating layer 730, a second blue emitting unit 740 (which includes a second blue emitting layer (not shown)), a second charge generating layer 750, a third blue emitting unit 760 (which includes a third blue emitting layer (not shown)), and a second electrode 770. The first blue emitting unit 720, the first charge generating layer 730, the second blue emitting unit 740, the second charge generating layer 750, and the third blue emitting unit 760 are all disposed between the first electrode 710 and the second electrode 770. The first blue emitting unit 720 is disposed above the first electrode 710. The first charge generating layer 730 is disposed above the first emitting unit 720. The second blue emitting unit 740 is disposed above the first charge generating layer 730. The second charge generating layer 750 is disposed above the second emitting unit 740. The third blue emitting unit 760 is disposed above the second charge generating layer 750. The second electrode 770 is disposed above the third blue emitting unit 760. In each configuration, the first blue emitting layer, the second blue emitting layer, and the third blue emitting layer each comprise an organic light-emitting material, a quantum dot light-emitting material, and / or a perovskite light-emitting material.

[0186] In one embodiment, the first blue emitting unit 720 emits blue light, the second blue emitting unit 740 emits blue light, and the third blue emitting unit 760 emits blue light. In one embodiment, the first blue emitting unit 720, the second blue emitting unit 740, and the third blue emitting unit 760 can all emit blue light in the visible spectrum with peak wavelengths in the range of 380 nm to 500 nm.

[0187] In one implementation scheme, such as Figure 16 As depicted in device 1610, the first blue emitting unit 720 emits a lighter blue light, the second blue emitting unit 740 emits a darker blue light, and the third blue emitting unit 760 emits a darker blue light. In one embodiment, as... Figure 16 As depicted in device 1620 of b, the first blue emitting unit 720 emits a deeper blue light, the second blue emitting unit 740 emits a deeper blue light, and the third blue emitting unit 760 emits a lighter blue light. In one embodiment, as... Figure 16 As depicted in device 1630 of c, the first blue emitting unit 720 emits a deeper blue light, the second blue emitting unit 740 emits a lighter blue light, and the third blue emitting unit 760 emits a deeper blue light. In one embodiment, as... Figure 16 As depicted in device 1640 of d, the first blue emitting unit 720 emits a lighter blue light, the second blue emitting unit 740 emits a lighter blue light, and the third blue emitting unit 760 emits a darker blue light. In one embodiment, as... Figure 16 As depicted in device 1650 of e, the first blue emitting unit 720 emits a deeper blue light, the second blue emitting unit 740 emits a lighter blue light, and the third blue emitting unit 760 emits a lighter blue light. In one embodiment, as... Figure 16 As depicted in device 1660 of f, the first blue emitting unit 720 can emit a lighter blue light, the second blue emitting unit 740 can emit a darker blue light, and the third blue emitting unit 760 can emit a lighter blue light.

[0188] In one embodiment, a first blue emitting unit 720 emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm, a second blue emitting unit 740 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm, and a third blue emitting unit 760 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm. In one embodiment, the first blue emitting unit 720 emits blue light with a CIE 1931y coordinate greater than 0.080, the second blue emitting unit 740 emits blue light with a CIE 1931y coordinate of 0.080 or less, and the third blue emitting unit 760 emits blue light with a CIE 1931y coordinate of 0.080 or less.

[0189] In one embodiment, a first blue emitting unit 720 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm, a second blue emitting unit 740 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm, and a third blue emitting unit 760 emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm. In one embodiment, the first blue emitting unit 720 emits blue light with a CIE 1931y coordinate of 0.080 or less, the second blue emitting unit 740 emits blue light with a CIE 1931y coordinate of 0.080 or less, and the third blue emitting unit 760 emits blue light with a CIE 1931y coordinate greater than 0.080.

[0190] In one embodiment, a first blue emitting unit 720 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm, a second blue emitting unit 740 emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm, and a third blue emitting unit 760 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm. In another embodiment, the first blue emitting unit 720 emits blue light with a CIE 1931y coordinate of 0.080 or less, the second blue emitting unit 740 emits blue light with a CIE 1931y coordinate greater than 0.080, and the third blue emitting unit 760 emits blue light with a CIE 1931y coordinate of 0.080 or less.

[0191] In one embodiment, a first blue emitting unit 720 emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm, a second blue emitting unit 740 emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm, and a third blue emitting unit 760 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm. In one embodiment, the first blue emitting unit 720 emits blue light with a CIE 1931y coordinate greater than 0.080, the second blue emitting unit 740 emits blue light with a CIE 1931y coordinate greater than 0.080, and the third blue emitting unit 760 emits blue light with a CIE 1931y coordinate of 0.080 or less.

[0192] In one embodiment, a first blue emitting unit 720 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm, a second blue emitting unit 740 emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm, and a third blue emitting unit 760 emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm. In one embodiment, the first blue emitting unit 720 emits blue light with a CIE 1931y coordinate of 0.080 or less, the second blue emitting unit 740 emits blue light with a CIE 1931y coordinate greater than 0.080, and the third blue emitting unit 760 emits blue light with a CIE 1931y coordinate greater than 0.080.

[0193] In one embodiment, a first blue emitting unit 720 emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm, a second blue emitting unit 740 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm, and a third blue emitting unit 760 emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm. In another embodiment, the first blue emitting unit 720 emits blue light with a CIE 1931y coordinate greater than 0.080, the second blue emitting unit 740 emits blue light with a CIE 1931y coordinate of 0.080 or less, and the third blue emitting unit 760 emits blue light with a CIE 1931y coordinate greater than 0.080.

[0194] Such exemplary embodiments can be implemented using any suitable combination of luminescent materials from the light blue OLED device, dark blue OLED device, dark blue QLED device and / or dark blue PeLED device described in Table 1.

[0195] In one embodiment, the third chromaticity is substantially the same as one of the first and second chromaticities; and the third chromaticity is substantially different from one of the first and second chromaticities. In one embodiment, the third chromaticity is substantially the same as the first chromaticity and substantially different from the second chromaticity. In one embodiment, the third chromaticity is substantially the same as the second chromaticity and substantially different from the first chromaticity.

[0196] To demonstrate such a stacked blue light emitting device, it is required that three or more emitting units be independently addressable, allowing them to emit light independently of each other. In one embodiment, the first, second, and third emitting units are independently addressable and can emit light independently of each other. Figure 7 This can be achieved if one or more charge-generating layers are directly connected to an external power source, as depicted.

[0197] In one implementation scheme, such as Figure 7 As depicted in arrangement 700, the first electrode 710 is directly connected to an external power supply E1, the second electrode 770 is directly connected to an external power supply E2, the first charge generation layer 730 is directly connected to an external power supply E3, and the second charge generation layer 750 is directly connected to an external power supply E4. The first transmitting unit is independently addressable; for a standard device architecture, E1 is placed at a positive potential relative to E3, or for an inverted device architecture, E1 is placed at a negative potential relative to E3. The second transmitting unit is independently addressable; for a standard device architecture, E3 is placed at a positive potential relative to E4, or for an inverted device architecture, E3 is placed at a negative potential relative to E4. The third transmitting unit is independently addressable; for a standard device architecture, E4 is placed at a positive potential relative to E2, or for an inverted device architecture, E4 is placed at a negative potential relative to E2.

[0198] In one embodiment, the first blue emitting unit 720, the second blue emitting unit 740, and the third blue emitting unit 760 may all be jointly addressable and may emit light independently of each other. In another embodiment, the first blue emitting unit 720, the second blue emitting unit 740, and the third blue emitting unit 760 may all be independently addressable and may emit light independently of each other. In yet another embodiment, at least one emitting unit may be independently addressable and may emit light independently of the other two emitting units, while the other two emitting units may be jointly addressable and may emit light independently of each other.

[0199] In one embodiment, the third transmitting unit 760 is addressed together with one of the first transmitting unit 720 and the second transmitting unit 740 and can transmit light independently of one of the first transmitting unit 720 and the second transmitting unit 740; and the third transmitting unit 760 is addressed independently of one of the first transmitting unit 720 and the second transmitting unit 740 and can transmit light independently of one of the first transmitting unit 720 and the second transmitting unit 740. In one embodiment, the third transmitting unit 760 is co-addressed with one of the first transmitting unit 720 and the second transmitting unit 740 and can emit light independently of one of the first transmitting unit 720 and the second transmitting unit 740; the third transmitting unit 760 is addressed independently of one of the first transmitting unit 720 and the second transmitting unit 740 and can emit light independently of one of the first transmitting unit 720 and the second transmitting unit 740; wherein the transmitting unit co-addressed with the third transmitting unit 760 has substantially the same chromaticity as the third transmitting unit 760; and the transmitting unit addressed independently of the third transmitting unit 760 has substantially different chromaticity from the third transmitting unit 760.

[0200] In one embodiment, a lighter blue emitting unit may be co-addressed with another lighter blue emitting unit and may emit light independently of the other lighter blue emitting unit. In one embodiment, a darker blue emitting unit may be co-addressed with another darker blue emitting unit and may emit light independently of the other darker blue emitting unit. In one embodiment, a lighter blue emitting unit may be addressed independently of a darker blue emitting unit and may emit light independently of the darker blue emitting unit. In one embodiment, a darker blue emitting unit may be addressed independently of a lighter blue emitting unit and may emit light independently of the lighter blue emitting unit.

[0201] For example, in Figure 16 In device 1610 of a, the lighter blue first emitting unit 720 can emit light independently of both the darker blue second emitting unit 740 and the darker blue third emitting unit 760, while the darker blue second emitting unit 740 and the darker blue third emitting unit 760 can be co-addressable and can emit light without being independent of each other.

[0202] In one embodiment, the third chromaticity coordinates (x3, y3) are not contained within a first-order McAdam ellipse centered at the first chromaticity coordinates (x1, y1), but are contained within a first-order McAdam ellipse centered at the second chromaticity coordinates (x2, y2). In another embodiment, the third chromaticity coordinates (x3, y3) are not contained within a first-order McAdam ellipse centered at the second chromaticity coordinates (x2, y2), but are contained within a first-order McAdam ellipse centered at the first chromaticity coordinates (x1, y1). In yet another embodiment, the third chromaticity coordinates (x3, y3) are not contained within a third-order McAdam ellipse centered at the first chromaticity coordinates (x1, y1), but are contained within a third-order McAdam ellipse centered at the second chromaticity coordinates (x2, y2). In yet another embodiment, the third chromaticity coordinates (x3, y3) are not contained within a third-order McAdam ellipse centered at the second chromaticity coordinates (x2, y2), but are contained within a third-order McAdam ellipse centered at the first chromaticity coordinates (x1, y1).

[0203] In one implementation, the chromaticity coordinates (x3, y3) of the third CIE 1931 (x, y) color space can be converted to the chromaticity coordinates (u3, v3) of the third CIE 1976 (u', v') color space. In one implementation, the third chromaticity coordinates (u3, v3) and the first chromaticity coordinates (u1, v1) are sufficiently different such that Δuv = √((u3 – u1) 2 +(v3–v1) 2The chromaticity difference is defined as 0.010 or greater; however, the third chromaticity coordinates (u3, v3) and the second chromaticity coordinates (u2, v2) are sufficiently similar, such that Δuv = √((u3 – u2)). 2 +(v3–v2) 2 The chromaticity difference defined is less than 0.010. In one implementation, the third chromaticity coordinates (u3, v3) and the second chromaticity coordinates (u2, v2) are sufficiently different such that Δuv = √((u3 – u2)). 2 +(v3–v2) 2 The chromaticity difference is defined as 0.010 or greater; and the third chromaticity coordinates (u3, v3) and the first chromaticity coordinates (u1, v1) are sufficiently similar, such that Δuv = √((u3 – u1)). 2 +(v3–v1) 2 The defined chromaticity difference is less than 0.010.

[0204] In one embodiment, the third peak wavelength is at least 4 nm larger or smaller than the first peak wavelength; however, the third peak wavelength is within 4 nm of the second peak wavelength.

[0205] The advantage of such devices, which include three or more blue emitting units within a stacked blue light emitting device architecture, is that light from more blue emitting units can be combined in the same surface area of ​​the device, thereby increasing the brightness of the device; and multiple emitting units can be electrically connected in series, with substantially the same current passing through each emitting unit, thereby allowing the device to operate with increased brightness without a significant increase in current density, thus extending the operating life of the device.

[0206] In one embodiment, the stacked blue light emitting device may include a microcavity structure. Optionally, as described herein, the microcavity structure may be created using a combination of a transparent and partially reflective electrode and an opposite reflective electrode. Optionally, in a standard device architecture, the bottom emitting microcavity structure may be created using a combination of a transparent and partially reflective multilayer anode (such as ITO / Ag / ITO) with an Ag thickness of less than about 25 nm and a reflective multilayer cathode (such as LiF / Al). In this architecture, light emission is through the anode. Optionally, in a standard device architecture, the top emitting microcavity structure may be created using a combination of a transparent and partially reflective composite cathode (such as Mg:Ag) and a reflective multilayer anode (such as ITO / Ag / ITO) with an Ag thickness of greater than about 80 nm. In this architecture, light emission is through the cathode.

[0207] The advantages of this device include: the microcavity structure increases the total amount of light emitted from the device, thereby increasing its efficiency and brightness. Another advantage is that the microcavity structure increases the proportion of light emitted in the positive direction, thus increasing the apparent brightness of the device positioned with normal incidence. A further advantage is that the microcavity structure narrows the spectrum of the emitted light, thereby increasing the color saturation of the emitted light. The application of this microcavity structure to the device enables it to render primary colors of the DCI-P3 color gamut. The application of this microcavity structure to the device also enables it to render colors of the Rec.2020 color gamut.

[0208] In one embodiment, the device is part of a display. In another embodiment, the device may be included in a subpixel of the display. Optionally, the display can be incorporated into a wide range of consumer products. Optionally, the display can be used in televisions, computer monitors, tablets, laptops, smartphones, mobile phones, digital cameras, video recorders, smartwatches, fitness trackers, personal digital assistants, vehicle displays, and other electronic devices. Optionally, the display can be used in microdisplays or head-up displays. Optionally, the display can be used as a light source for internal or external lighting and / or signal transmission, for smart packaging or billboards.

[0209] Figure 17 An exemplary design for the subpixel is depicted. Figure 17 The arrangement 1700 includes three adjacent sub-pixels, each sub-pixel having a length of L and a width of W. The first sub-pixel 1710 may include a red sub-pixel, wherein such a red sub-pixel may include, for example, Figure 6 or Figure 7 The image depicts a stacked blue light emitting device optically coupled to a red color conversion layer. The second sub-pixel 1720 may include a green sub-pixel, wherein such a green sub-pixel may include, for example... Figure 6 or Figure 7 The image depicts a stacked blue light emitting device optically coupled to a green color conversion layer. The third sub-pixel 1730 may include a blue sub-pixel, wherein such a blue sub-pixel may include, for example... Figure 6 or Figure 7 The image depicts a stacked blue light emitting device. Typical pixel arrangements for commercial displays may include subpixel arrangements such as 1700.

[0210] A display is provided. In one embodiment, the display includes components that can be... Figure 17 The subpixels are arranged as depicted in the diagram 1700. See also... Figure 21 The arrangement depicted in the image 2100 is used to further understand the display.

[0211] In one embodiment, the display includes: a first sub-pixel 1710 configured to emit red light in the visible spectrum with a peak wavelength in the range of 580 nm to 780 nm; a second sub-pixel 1720 configured to emit green light in the visible spectrum with a peak wavelength in the range of 500 nm to 580 nm; and a third sub-pixel 1730 configured to emit blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm; wherein the first sub-pixel 1710 includes a first stack optically coupled to a red color conversion layer 2170. The first sub-pixel 1705 includes a blue light emitting device 2105; the second sub-pixel 1720 includes a second stacked blue light emitting device 2115 optically coupled to a green color conversion layer 2180; and the third sub-pixel 1730 includes a third stacked blue light emitting device 2125; wherein all the first stacked blue light emitting devices 1705, the second stacked blue light emitting devices 1715, and the third stacked blue light emitting devices 1725 include: a first electrode 2120; a second electrode 2160; a first emitting unit 2130, the first emitting unit including a first emitting layer (not shown); a second emitting layer; and a third emitting layer. Unit 2150, the second emitting unit includes a second emitting layer (not shown); and a first charge generating layer 2140; wherein the first emitting unit 2130, the second emitting unit 2150 and the first charge generating layer 2140 are all disposed between the first electrode 2120 and the second electrode 2160; the first emitting unit 2130 is disposed above the first electrode 2120; the first charge generating layer 2140 is disposed above the first emitting unit 2130; the second emitting unit 2150 is disposed above the first charge generating layer 2140; and the second electrode 2160 is disposed on the second emitting unit 2150. The first emitting unit 2130 emits blue light in the visible spectrum with a peak wavelength in the range of 380nm to 500nm, and this peak wavelength is defined as the first peak wavelength; the first emitting unit 2130 emits blue light with chromaticity coordinates of (x1, y1) in the first CIE 1931 (x, y) color space; the second emitting unit 2150 emits blue light in the visible spectrum with a peak wavelength in the range of 380nm to 500nm, and this peak wavelength is defined as the second peak wavelength; the second emitting unit 2150 emits blue light with a second chromaticity, and the second chromaticity has chromaticity coordinates of (x2, y2) in the second CIE 1931 (x, y) color space; the second chromaticity is substantially different from the first chromaticity; and the first emitting layer and the second emitting layer include organic light-emitting materials, quantum dot light-emitting materials and / or perovskite light-emitting materials.

[0212] In one embodiment, for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting devices 2115, and the third stacked blue light emitting devices 2125, the second chromaticity coordinates (x2, y2) measured for light emitted from the second emitting unit 2150 are not included in a first-order McAdam ellipse centered on the first chromaticity coordinates (x1, y1) measured for light emitted from the first emitting unit 2130. In another embodiment, for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting devices 2115, and the third stacked blue light emitting devices 2125, the second chromaticity coordinates (x2, y2) measured for light emitted from the second emitting unit 2150 are not included in a third-order McAdam ellipse centered on the first chromaticity coordinates (x1, y1) measured for light emitted from the first emitting unit 2130.

[0213] In one implementation, the chromaticity coordinates (x1, y1) of the first CIE 1931 (x, y) color space can be converted to the chromaticity coordinates (u1, v1) of the first CIE 1976 (u', v') color space; and the chromaticity coordinates (x2, y2) of the second CIE 1931 (x, y) color space can be converted to the chromaticity coordinates (u2, v2) of the second CIE 1976 (u', v') color space; wherein for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting device 2115, and the third stacked blue light emitting device 2125, the first chromaticity coordinates (u1, v1) of the light emitted from the first blue emitting unit 2130 and the second chromaticity coordinates (u2, v2) of the light emitted from the second blue emitting unit 2150 are sufficiently different, such that the chromaticity difference defined by Δuv is 0.010 or greater.

[0214] In one embodiment, for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting device 2115 and the third stacked blue light emitting device 2125, the second peak wavelength of the light emitted from the second emitting unit 2150 is at least 4 nm larger or at least 4 nm smaller than the first peak wavelength of the light emitted from the first emitting unit 2130.

[0215] In one embodiment, for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting device 2115, and the third stacked blue light emitting device 2125, the first blue emitting unit 2130 can emit blue light, and the second blue emitting unit 2150 can emit blue light. In one embodiment, for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting device 2115, and the third stacked blue light emitting device 2125, both the first blue emitting unit 2130 and the second blue emitting unit 2150 can emit blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm. In one embodiment, for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting device 2115, and the third stacked blue light emitting device 2125, the first blue emitting unit 2130 can emit a lighter blue light, and the second blue emitting unit 2150 can emit a darker blue light. In one embodiment, for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting device 2115, and the third stacked blue light emitting device 2125, the first blue emitting unit 2130 can emit a deeper blue light, and the second blue emitting unit 2150 can emit a lighter blue light.

[0216] In one embodiment, the first blue emitting unit 2130 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm; and for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting device 2115, and the third stacked blue light emitting device 2125, the second blue emitting unit 2150 emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm. In one embodiment, the first blue emitting unit 2130 emits blue light with a CIE 1931y coordinate of 0.080 or less; and for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting device 2115, and the third stacked blue light emitting device 2125, the second blue emitting unit 2150 emits blue light with a CIE 1931y coordinate greater than 0.080. In one embodiment, the second blue emitting unit 2150 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm; and for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting device 2115, and the third stacked blue light emitting device 2125, the first blue emitting unit 2130 emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm. In one embodiment, the second blue emitting unit 2150 emits blue light with a CIE 1931y coordinate of 0.080 or less; and for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting device 2115, and the third stacked blue light emitting device 2125, the first blue emitting unit 2130 emits blue light with a CIE 1931y coordinate greater than 0.080.

[0217] Such exemplary embodiments can be implemented using any suitable combination of luminescent materials from the light blue OLED device, dark blue OLED device, dark blue QLED device and / or dark blue PeLED device described in Table 1.

[0218] In one embodiment, the first stacked blue light emitting device 2105, the second stacked blue light emitting device 2115, and the third stacked blue light emitting device 2125 all have the same device architecture. That is, the first stacked blue light emitting device 2105, the second stacked blue light emitting device 2115, and the third stacked blue light emitting device 2125 all include the same device layers, which are arranged in the same configuration and include the same proportion of the same materials. In other words, the first stacked blue light emitting device 2105, the second stacked blue light emitting device 2115, and the third stacked blue light emitting device 2125 all have the same optoelectronic performance.

[0219] In one embodiment, the first emitting unit 2130 and the second emitting unit 2150 of any of the first stacked blue light emitting device 2105, the second stacked blue light emitting device 2125, and the third stacked blue light emitting device 2125 are co-addressable and can emit light independently of each other. In another embodiment, the first emitting unit 2130 and the second emitting unit 2150 of any of the first stacked blue light emitting device 2105, the second stacked blue light emitting device 2125, and the third stacked blue light emitting device 2125 are independently addressable and can emit light independently of each other.

[0220] In one embodiment, the first emitting units 2130 and second emitting units 2150 of all the first stacked blue light emitting devices 2105, the second stacked blue light emitting devices 2125, and the third stacked blue light emitting devices 2125 are co-addressable and can emit light independently of each other. In another embodiment, the first emitting units 2130 and second emitting units 2150 of all the first stacked blue light emitting devices 2105, the second stacked blue light emitting devices 2125, and the third stacked blue light emitting devices 2125 are independently addressable and can emit light independently of each other.

[0221] In one embodiment, the first emitting unit 2130 and the second emitting unit 2150 of the third stacked blue light emitting device 2125 are independently addressable and can emit light independently of each other, and the first emitting unit 2130 and the second emitting unit 2150 of the first stacked blue light emitting device 2105 are jointly addressable and can emit light not independently of each other, and the first emitting unit 2130 and the second emitting unit 2150 of the second stacked blue light emitting device 2115 are jointly addressable and can emit light not independently of each other.

[0222] In one preferred embodiment, for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting devices 2125, and the third stacked blue light emitting devices 2125, the first blue emitting layer and the second blue emitting layer comprise organic light-emitting materials. In one embodiment, for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting devices 2125, and the third stacked blue light emitting devices 2125, the first blue emitting layer and the second blue emitting layer comprise fluorescent organic light-emitting materials. In one embodiment, for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting devices 2125, and the third stacked blue light emitting devices 2125, the first blue emitting layer and the second blue emitting layer comprise phosphorescent organic light-emitting materials.

[0223] In one embodiment, at least one of the first and second emitting layers comprises a phosphorescent organic light-emitting material; and for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting devices 2125, and the third stacked blue light emitting devices 2125, at least one of the first and second emitting layers comprises a fluorescent organic light-emitting material. In a preferred embodiment, the first blue emitting layer is a light blue emitting layer comprising a phosphorescent organic light-emitting material; and for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting devices 2125, and the third stacked blue light emitting devices 2125, the second blue emitting layer is a dark blue emitting layer comprising a fluorescent organic light-emitting material. In a preferred embodiment, the first blue emitting layer is a dark blue emitting layer comprising a fluorescent organic light-emitting material; and for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting devices 2125, and the third stacked blue light emitting devices 2125, the second blue emitting layer is a light blue emitting layer comprising a phosphorescent organic light-emitting material. Such stacked blue light emitting device architectures can be advantageous because more efficient but less stable phosphorescent organic materials can emit light blue light to render a light blue color, while less efficient but more stable fluorescent organic materials can emit dark blue light to render a dark blue color.

[0224] In one embodiment, for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting devices 2125, and the third stacked blue light emitting devices 2125, the first blue emitting layer and the second blue emitting layer comprise quantum dot luminescent materials. In another embodiment, for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting devices 2125, and the third stacked blue light emitting devices 2125, the first blue emitting layer and the second blue emitting layer comprise perovskite luminescent materials.

[0225] In one embodiment, for all the first stacked blue light emitting devices 2105, the second stacked blue light emitting devices 2125, and the third stacked blue light emitting devices 2125, the first blue emitting layer includes a first type of blue luminescent material, which is an organic luminescent material, a quantum dot luminescent material, or a perovskite luminescent material; and the second blue emitting layer includes a second type of blue luminescent material, which is an organic luminescent material, a quantum dot luminescent material, or a perovskite luminescent material; wherein the second type of blue luminescent material is different from the first type of blue luminescent material. In a preferred embodiment, the first blue emitting layer includes an organic luminescent material, and the second blue emitting layer includes a quantum dot luminescent material or a perovskite luminescent material.

[0226] In one implementation scheme, such as Figure 22The arrangement 2200 depicted in the diagram further includes: a third emitting unit 2220, comprising a third emitting layer (not shown); and a second charge generating layer 2210; wherein the third emitting unit 2220 and the second charge generating layer 2210 are disposed between the second emitting unit 2150 and the second electrode 2160; the second charge generating layer 2210 is disposed above the second emitting unit 2150; the third emitting unit... The second electrode 2220 is disposed above the second charge generation layer 2210; the second electrode 2160 is disposed above the third emission unit 2220; the third emission unit 2220 emits blue light in the visible spectrum with a peak wavelength in the range of 380nm to 500nm, and the peak wavelength is defined as the third peak wavelength; the third emission unit 2220 emits blue light with a third chromaticity, and the chromaticity coordinates of the third CIE1931(x,y) color space of the third chromaticity are (x3,y3); and the third emission layer includes organic light-emitting material, quantum dot light-emitting material or perovskite light-emitting material.

[0227] In one embodiment, for all the first stacked blue light emitting devices 2205, the second stacked blue light emitting devices 2215, and the third stacked blue light emitting devices 2225, the third chromaticity is substantially the same as the first chromaticity and substantially different from the second chromaticity.

[0228] In one embodiment, for all the first stacked blue light emitting devices 2205, the second stacked blue light emitting devices 2215, and the third stacked blue light emitting devices 2225, the third chromaticity coordinate (x3, y3) is not contained within a first-order McAdam ellipse centered at the first chromaticity coordinate (x1, y1), but rather within a first-order McAdam ellipse centered at the second chromaticity coordinate (x2, y2). In another embodiment, for all the first stacked blue light emitting devices 2205, the second stacked blue light emitting devices 2215, and the third stacked blue light emitting devices 2225, the third chromaticity coordinate (x3, y3) is not contained within a first-order McAdam ellipse centered at the second chromaticity coordinate (x2, y2), but rather within a first-order McAdam ellipse centered at the first chromaticity coordinate (x1, y1). In one embodiment, for all the first stacked blue light emitting devices 2205, the second stacked blue light emitting devices 2215, and the third stacked blue light emitting devices 2225, the third chromaticity coordinates (x3, y3) are not contained within a third-order McAdam ellipse centered at the first chromaticity coordinates (x1, y1), but are instead contained within a third-order McAdam ellipse centered at the second chromaticity coordinates (x2, y2). In another embodiment, for all the first stacked blue light emitting devices 2205, the second stacked blue light emitting devices 2215, and the third stacked blue light emitting devices 2225, the third chromaticity coordinates (x3, y3) are not contained within a third-order McAdam ellipse centered at the second chromaticity coordinates (x2, y2), but are instead contained within a third-order McAdam ellipse centered at the first chromaticity coordinates (x1, y1).

[0229] In one embodiment, for all the first stacked blue light emitters 2205, the second stacked blue light emitters 2215, and the third stacked blue light emitters 2225, the chromaticity coordinates (x3, y3) of the third CIE 1931 (x, y) color space can be converted to chromaticity coordinates (u3, v3) of the third CIE 1976 (u', v') color space. In one embodiment, for all the first stacked blue light emitters 2205, the second stacked blue light emitters 2215, and the third stacked blue light emitters 2225, the third chromaticity coordinates (u3, v3) and the first chromaticity coordinates (u1, v1) are sufficiently different such that Δuv = √((u3 – u1) 2 +(v3–v1) 2 The chromaticity difference is defined as 0.010 or greater; however, the third chromaticity coordinates (u3, v3) and the second chromaticity coordinates (u2, v2) are sufficiently similar, such that Δuv = √((u3 – u2)). 2 +(v3–v2) 2The chromaticity difference is defined as less than 0.010. In one embodiment, for all the first stacked blue light emitters 2205, the second stacked blue light emitters 2215, and the third stacked blue light emitters 2225, the third chromaticity coordinates (u3, v3) and the second chromaticity coordinates (u2, v2) are sufficiently different such that Δuv = √((u3 – u2) 2 +(v3–v2) 2 The chromaticity difference is defined as 0.010 or greater; however, the third chromaticity coordinates (u3, v3) and the first chromaticity coordinates (u1, v1) are sufficiently similar, such that Δuv = √((u3 – u1)). 2 +(v3–v1) 2 The defined chromaticity difference is less than 0.010.

[0230] In one embodiment, for all the first stacked blue light emitting devices 2205, the second stacked blue light emitting devices 2215, and the third stacked blue light emitting devices 2225, the third peak wavelength is at least 4 nm larger or smaller than the first peak wavelength; however, the third peak wavelength is within 4 nm of the second peak wavelength.

[0231] In one embodiment, for all the first stacked blue light emitting devices 2205, the second stacked blue light emitting device 2215, and the third stacked blue light emitting device 2225, the first blue emitting unit 2130, the second blue emitting unit 2150, and the third blue emitting unit 2220 can emit blue light. In one embodiment, for all the first stacked blue light emitting devices 2205, the second stacked blue light emitting device 2215, and the third stacked blue light emitting device 2225, the first blue emitting unit 2130, the second blue emitting unit 2150, and the third blue emitting unit 2220 can emit blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm. In one embodiment, for all the first stacked blue light emitting devices 2205, the second stacked blue light emitting device 2215, and the third stacked blue light emitting device 2225, the first blue emitting unit 2130 can emit a deeper blue light, the second blue emitting unit 2150 can emit a deeper blue light, and the third blue emitting unit 2220 can emit a lighter blue light. In another embodiment, for all the first stacked blue light emitting devices 2205, the second stacked blue light emitting device 2215, and the third stacked blue light emitting device 2225, the first blue emitting unit 2130 can emit a lighter blue light, the second blue emitting unit 2150 can emit a lighter blue light, and the third blue emitting unit 2220 can emit a deeper blue light. Other combinations of lighter and darker blue emitting units are also contemplated for any or all of the first stacked blue light emitting device 2205, the second stacked blue light emitting device 2215, and the third stacked blue light emitting device 2225.

[0232] In one embodiment, the first blue emitting unit 2130 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm; the second blue emitting unit 2150 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm; and for all the first stacked blue light emitting devices 2205, the second stacked blue light emitting device 2215, and the third stacked blue light emitting device 2225, the third blue emitting unit 2220 emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm. In one embodiment, the first blue emitting unit 2130 emits blue light with a CIE 1931y coordinate of 0.080 or less; the second blue emitting unit 2150 emits blue light with a CIE 1931y coordinate of 0.080 or less; and for all the first stacked blue light emitting devices 2205, the second stacked blue light emitting device 2215, and the third stacked blue light emitting device 2225, the third blue emitting unit 2220 emits blue light with a CIE 1931y coordinate greater than 0.080. In one embodiment, the first blue emitting unit 2130 emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm; and the second blue emitting unit 2150 emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm; and for all the first stacked blue light emitting devices 2205, the second stacked blue light emitting device 2215 and the third stacked blue light emitting device 2225, the third blue emitting unit 2220 emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm. In one embodiment, the first blue emitting unit 2130 emits blue light with a CIE 1931y coordinate greater than 0.080; the second blue emitting unit 2150 emits blue light with a CIE 1931y coordinate greater than 0.080; and for all the first stacked blue light emitting devices 2205, the second stacked blue light emitting device 2215, and the third stacked blue light emitting device 2225, the third blue emitting unit 2220 emits blue light with a CIE 1931y coordinate of 0.080 or less. Other combinations of lighter and darker blue emitting units are also contemplated for any or all of the first stacked blue light emitting device 2205, the second stacked blue light emitting device 2215, and the third stacked blue light emitting device 2225.

[0233] Such exemplary embodiments can be implemented using any suitable combination of luminescent materials from the light blue OLED device, dark blue OLED device, dark blue QLED device and / or dark blue PeLED device described in Table 1.

[0234] In one embodiment, for all the first stacked blue light emitters 2205, the second stacked blue light emitters 2215, and the third stacked blue light emitters 2225, the first blue emitting unit 2130, the second blue emitting unit 2150, and the third blue emitting unit 2220 can all be jointly addressable and can emit light independently of each other. In another embodiment, for all the first stacked blue light emitters 2205, the second stacked blue light emitters 2215, and the third stacked blue light emitters 2225, the first blue emitting unit 2130, the second blue emitting unit 2150, and the third blue emitting unit 2220 can all be independently addressable and can all emit light independently of each other. In one implementation, for all the first stacked blue light emitting devices 2205, the second stacked blue light emitting devices 2215 and the third stacked blue light emitting devices 2225, at least one emitting unit may be independently addressable and may emit light independently of the other two emitting units, while the other two emitting units may be jointly addressable and may not emit light independently of each other.

[0235] In one implementation, for all the first stacked blue light emitting devices 2205, the second stacked blue light emitting devices 2215, and the third stacked blue light emitting devices 2225, the third emitting unit 2220 is co-addressed with one of the first emitting units 2130 and the second emitting unit 2150 and can emit light independently of one of the first emitting units 2130 and the second emitting unit 2150; and the third emitting unit 2220 is addressed independently of one of the first emitting units 2130 and the second emitting unit 2150 and can emit light independently of one of the first emitting units 2130 and the second emitting unit 2150.

[0236] In one embodiment, for all the first stacked blue light emitting devices 2205, the second stacked blue light emitting devices 2215, and the third stacked blue light emitting devices 2225, the third emitting unit 2220 is co-addressed with one of the first emitting units 2130 and the second emitting unit 2150 and can emit light independently of one of the first emitting units 2130 and the second emitting unit 2150; the third emitting unit 2220 is addressed independently of one of the first emitting units 2130 and the second emitting unit 2150 and can emit light independently of one of the first emitting units 2130 and the second emitting unit 2150; wherein the emitting unit co-addressed with the third emitting unit 2220 has substantially the same chromaticity as the third emitting unit 2220; and the emitting unit addressed independently of the third emitting unit 2220 has substantially different chromaticity from the third emitting unit 2220.

[0237] In one embodiment, a lighter blue emitting unit may be co-addressed with another lighter blue emitting unit and may emit light independently of the other lighter blue emitting unit. In one embodiment, a darker blue emitting unit may be co-addressed with another darker blue emitting unit and may emit light independently of the other darker blue emitting unit. In one embodiment, a lighter blue emitting unit may be addressed independently of a darker blue emitting unit and may emit light independently of the darker blue emitting unit. In one embodiment, a darker blue emitting unit may be addressed independently of a lighter blue emitting unit and may emit light independently of the lighter blue emitting unit.

[0238] When implemented in a display, a stacked blue light emitting device, as disclosed herein, comprising two or more emitting units emitting light with substantially different chromaticities, is expected to enable the display to operate with improved efficiency and extended lifespan compared to a display comprising a single emitting unit device capable of rendering the same color gamut. This is because when the blue subpixels of such a display are required to emit relatively saturated blue light, the emitting unit emitting the deeper blue light can be individually addressed and can emit light to generate the display image, while the emitting unit emitting the lighter blue light can remain inactive. However, when only the blue subpixels of such a display are required to emit relatively unsaturated blue light, the emitting unit emitting the lighter blue light can be individually addressed and can emit light to generate the display image, while the emitting unit emitting the deeper blue light can remain inactive. Light can be emitted from the relatively more efficient and / or more stable lighter blue emitting unit to render most of the display image, while light emitted from the relatively less efficient and / or less stable darker blue emitting unit only needs to render a small portion of the image. This thus improves the efficiency and / or lifespan of the display. In addition, lighter blue emitting units can be used alone or in combination with darker blue emitting units to provide light to the red and green color conversion layers in the red and green subpixels.

[0239] This can be demonstrated by modeling the power consumption of the display when rendering a typical set of display images. An example of such modeling is described in U.S. Patent 9559151B2, which discloses a device that can be used as a multi-color pixel, wherein the device includes a first OLED, a second OLED, a third OLED, and a fourth OLED. This reference is incorporated herein by reference in its entirety. Note that the present invention represents a significant improvement over US 9559151B2 because it achieves equivalent energy savings and extended lifetime without requiring an additional fourth subpixel in the display, which reduces aperture ratio, efficiency, and lifetime, and increases complexity and cost. Furthermore, the present invention is compatible with the use of different types of luminescent materials, including organic luminescent materials, quantum dot luminescent materials, and perovskite luminescent materials.

[0240] In one embodiment, the stacked light-emitting device may be included in a lighting panel. Optionally, the lighting panel may be included in a wide range of consumer products. Optionally, the lighting panel may be used for external lighting and / or signal transmission in smart packaging or billboards.

[0241] Those skilled in the art will understand that only a few use cases have been described, but they are by no means limiting.

[0242] Modifications to the embodiments of the invention described above may be made without departing from the scope of the invention as defined by the appended claims. Expressions used to describe and claim the invention, such as “including,” “comprising,” “incorporating,” “consisting of,” “have,” and “is,” are intended to be interpreted in a non-exclusive manner, allowing for the presence of items, components, or elements not explicitly described. References to the singular should also be interpreted as referring to the plural. Any numbers included in parentheses in the appended claims are intended to aid in understanding the claims and should not in any way be construed as limiting the subject matter claimed by those claims.

[0243] Some embodiments of the present invention are as follows:

[0244] 1. An apparatus, the apparatus comprising:

[0245] A stacked blue light emitting device, the stacked blue light emitting device comprising:

[0246] First electrode;

[0247] Second electrode;

[0248] A first launching unit, the first launching unit including a first launching layer;

[0249] A second transmitting unit, the second transmitting unit including a second transmitting layer; and

[0250] First charge generation layer; wherein

[0251] The first transmitting unit, the second transmitting unit, and the first charge generating layer are all disposed between the first electrode and the second electrode;

[0252] The first transmitting unit is positioned above the first electrode;

[0253] The first charge generation layer is disposed above the first emission unit;

[0254] The second transmitting unit is positioned above the first charge generation layer;

[0255] The second electrode is positioned above the second transmitting unit;

[0256] The first emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm, and the peak wavelength is defined as the first peak wavelength;

[0257] The first emitting unit emits blue light with chromaticity coordinates (x1, y1) in the first CIE 1931 (x, y) color space;

[0258] The second emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm, and the peak wavelength is defined as the second peak wavelength;

[0259] The second emitting unit emits blue light with a second chromaticity, and the second chromaticity coordinates in the second CIE1931 (x,y) color space are (x2,y2);

[0260] The second chromaticity is substantially different from the first chromaticity; and

[0261] The first emitting layer and the second emitting layer include organic light-emitting materials, quantum dot light-emitting materials and / or perovskite light-emitting materials.

[0262] 2. The apparatus according to embodiment 1, wherein

[0263] The second chromaticity coordinates (x2, y2) are not contained within a first-order McAdam ellipse centered at the first chromaticity coordinates (x1, y1).

[0264] 3. The apparatus according to embodiment 1, wherein

[0265] The second chromaticity coordinates (x2, y2) are not contained within the third-order McAdam ellipse centered at the first chromaticity coordinates (x1, y1).

[0266] 4. The apparatus according to any one of embodiments 1 to 3, wherein the second peak wavelength is at least 4 nm larger or at least 4 nm smaller than the first peak wavelength.

[0267] 5. The apparatus according to any one of embodiments 1 to 3, wherein

[0268] The first CIE 1931 (x,y) color space chromaticity coordinates (x1,y1) can be converted to the first CIE1976 (u',v') color space chromaticity coordinates (u1,v1); and

[0269] The second CIE 1931 (x,y) color space chromaticity coordinates (x2,y2) can be converted to the second CIE1976 (u',v') color space chromaticity coordinates (u2,v2); where

[0270] The first chromaticity coordinates (u1, v1) and the second chromaticity coordinates (u2, v2) are sufficiently different such that the chromaticity difference defined by Δuv is 0.010 or greater.

[0271] 6. The apparatus according to any one of embodiments 1 to 5, wherein the first emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm; and the second emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm.

[0272] 7. The apparatus according to any one of embodiments 1 to 5, wherein the first emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm; and the second emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm.

[0273] 8. The apparatus according to any one of embodiments 1 to 5, wherein the first emitting unit emits blue light with a CIE1931y coordinate of 0.080 or less; and the second emitting unit emits blue light with a CIE1931y coordinate greater than 0.080.

[0274] 9. The apparatus according to any one of embodiments 1 to 5, wherein the first emitting unit emits blue light with a CIE 1931y coordinate greater than 0.080; and the second emitting unit emits blue light with a CIE 1931y coordinate of 0.080 or less.

[0275] 10. The apparatus according to any one of embodiments 1 to 9, wherein the first emitting layer and the second emitting layer comprise organic light-emitting materials.

[0276] 11. The apparatus according to embodiment 10, wherein

[0277] At least one of the first emitting layer and the second emitting layer comprises a phosphorescent organic light-emitting material; and

[0278] At least one of the first emitting layer and the second emitting layer comprises a fluorescent organic light-emitting material.

[0279] 12. The apparatus according to any one of embodiments 1 to 9, wherein the first emitting layer and the second emitting layer comprise quantum dot luminescent materials.

[0280] 13. The apparatus according to any one of embodiments 1 to 9, wherein the first emitting layer and the second emitting layer comprise a perovskite luminescent material.

[0281] 14. The apparatus according to any one of embodiments 1 to 9, wherein

[0282] The first emitting layer includes a first type of luminescent material, which is an organic luminescent material, a quantum dot luminescent material, or a perovskite luminescent material;

[0283] The second emitting layer includes a second type of luminescent material, which is an organic luminescent material, a quantum dot luminescent material, or a perovskite luminescent material; and

[0284] The second type of luminescent material is different from the first type of luminescent material.

[0285] 15. The apparatus according to any one of embodiments 1 to 14, wherein the first transmitting unit and the second transmitting unit are independently addressable and can emit light independently of each other.

[0286] 16. The apparatus according to any one of embodiments 1 to 14, wherein the first transmitting unit and the second transmitting unit are co-addressable and can transmit light independently of each other.

[0287] 17. The apparatus according to any one of embodiments 1 to 16, wherein the stacked blue light emitting device further comprises:

[0288] A third transmitting unit, the third transmitting unit including a third transmitting layer; and

[0289] The second charge generation layer; wherein

[0290] The third emitting unit and the second charge generating layer are disposed between the second emitting unit and the second electrode;

[0291] The second charge generation layer is disposed above the second emission unit;

[0292] The third emission unit is positioned above the second charge generation layer;

[0293] The second electrode is positioned above the third transmitting unit;

[0294] The third emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm, and the peak wavelength is defined as the third peak wavelength;

[0295] The third emission unit emits blue light with chromaticity coordinates (x3, y3) in the first CIE 1931 (x, y) color space; and

[0296] The third emitting layer includes organic light-emitting materials, quantum dot light-emitting materials, or perovskite light-emitting materials.

[0297] 18. The apparatus according to embodiment 17, wherein

[0298] The third chromaticity is substantially the same as one of the first chromaticity and the second chromaticity; and

[0299] The third chromaticity is substantially different from either the first chromaticity or the second chromaticity.

[0300] 19. The apparatus according to embodiment 17, wherein

[0301] The third transmitting unit shares an address with one of the first and second transmitting units and can emit light independently of either the first or second transmitting unit; and

[0302] The third transmitting unit is addressed independently of either the first or the second transmitting unit and can emit light independently of either the first or the second transmitting unit.

[0303] 20. The apparatus according to embodiment 17, wherein

[0304] The third transmitting unit shares an address with one of the first transmitting unit and the second transmitting unit and can transmit light without being independent of one of the first transmitting unit and the second transmitting unit;

[0305] The third transmitting unit is addressed independently of either the first or the second transmitting unit and can emit light independently of either the first or the second transmitting unit; wherein

[0306] The transmitting unit that is addressed together with the third transmitting unit has substantially the same chromaticity as the third transmitting unit; and

[0307] The transmitting unit addressed independently of the third transmitting unit has a chromaticity that is substantially different from that of the third transmitting unit.

[0308] 21. The device according to any one of embodiments 1 to 20, wherein the device is part of a lighting panel.

[0309] 22. The apparatus according to any one of embodiments 1 to 20, wherein the apparatus is part of a display.

[0310] 23. A display is provided, wherein the display includes:

[0311] The first sub-pixel is configured to emit red light in the visible spectrum with a peak wavelength in the range of 580 nm to 780 nm;

[0312] The second sub-pixel is configured to emit green light in the visible spectrum with a peak wavelength in the range of 500 nm to 580 nm; and

[0313] The third sub-pixel is configured to emit blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm; wherein

[0314] The first sub-pixel includes a first stacked blue light emitting device optically coupled to the red color conversion layer;

[0315] The second sub-pixel includes a second stacked blue light emitting device optically coupled to the green color conversion layer; and

[0316] The third sub-pixel includes a third stacked blue light emitting device; wherein

[0317] All of the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices include the stacked blue light emitting device according to embodiment 1.

[0318] 24. The display according to embodiment 23, wherein

[0319] For all the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices, the second chromaticity coordinates (x2, y2) are not contained within a first-order McAdam ellipse centered at the first chromaticity coordinates (x1, y1).

[0320] 25. The display according to embodiment 23, wherein

[0321] For all the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices, the second chromaticity coordinates (x2, y2) are not contained within a third-order McAdam ellipse centered at the first chromaticity coordinates (x1, y1).

[0322] 26. The display according to any one of embodiments 23 to 25, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices and the third stacked blue light emitting devices, the second peak wavelength is at least 4 nm larger or at least 4 nm smaller than the first peak wavelength.

[0323] 27. The display according to any one of embodiments 23 to 25, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices:

[0324] The first CIE 1931 (x,y) color space chromaticity coordinates (x1,y1) can be converted to the first CIE1976 (u',v') color space chromaticity coordinates (u1,v1); and

[0325] The second CIE 1931 (x,y) color space chromaticity coordinates (x2,y2) can be converted to the second CIE1976 (u',v') color space chromaticity coordinates (u2,v2); where

[0326] The first chromaticity coordinates (u1, v1) and the second chromaticity coordinates (u2, v2) are sufficiently different such that the chromaticity difference defined by Δuv is 0.010 or greater.

[0327] 28. The display according to any one of embodiments 23 to 27, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices and the third stacked blue light emitting devices, the first emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm; and the second emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm.

[0328] 29. The display according to any one of embodiments 23 to 27, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices and the third stacked blue light emitting devices, the first emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm; and the second emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm.

[0329] 30. The display according to any one of embodiments 23 to 27, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices and the third stacked blue light emitting devices, the first emitting unit emits blue light with a CIE 1931y coordinate of 0.080 or less; and the second emitting unit emits blue light with a CIE 1931y coordinate greater than 0.080.

[0330] 31. The display according to any one of embodiments 23 to 27, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices and the third stacked blue light emitting devices, the first emitting unit emits blue light with a CIE 1931y coordinate greater than 0.080; and the second emitting unit emits blue light with a CIE 1931y coordinate of 0.080 or less.

[0331] 32. The display according to any one of embodiments 23 to 31, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices and the third stacked blue light emitting devices, the first emitting layer and the second emitting layer comprise an organic light-emitting material.

[0332] 33. The display according to embodiment 32, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices:

[0333] At least one of the first emitting layer and the second emitting layer comprises a phosphorescent organic light-emitting material; and

[0334] At least one of the first emitting layer and the second emitting layer comprises a fluorescent organic light-emitting material.

[0335] 34. The display according to any one of embodiments 23 to 31, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices and the third stacked blue light emitting devices, the first emitting layer and the second emitting layer comprise quantum dot luminescent material.

[0336] 35. The display according to any one of embodiments 23 to 31, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices and the third stacked blue light emitting devices, the first emitting layer and the second emitting layer comprise a perovskite luminescent material.

[0337] 36. The display according to any one of embodiments 23 to 31, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices:

[0338] The first emitting layer includes a first type of luminescent material, which is an organic luminescent material, a quantum dot luminescent material, or a perovskite luminescent material;

[0339] The second emitting layer includes a second type of luminescent material, which is an organic luminescent material, a quantum dot luminescent material, or a perovskite luminescent material; and

[0340] The second type of luminescent material is different from the first type of luminescent material.

[0341] 37. The display according to any one of embodiments 23 to 36, wherein the first stacked blue light emitting device, the second stacked blue light emitting device and the third stacked blue light emitting device all have the same device architecture.

[0342] 38. The display according to any one of embodiments 23 to 37, wherein for any one of the first stacked blue light emitting device, the second stacked blue light emitting device, and the third stacked blue light emitting device, the first emitting unit and the second emitting unit are independently addressable and can emit light independently of each other.

[0343] 39. The display according to any one of embodiments 23 to 37, wherein for any one of the first stacked blue light emitting device, the second stacked blue light emitting device, and the third stacked blue light emitting device, the first emitting unit and the second emitting unit are co-addressable and can emit light independently of each other.

[0344] 40. The display according to any one of embodiments 23 to 37, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices and the third stacked blue light emitting devices, the first emitting unit and the second emitting unit are independently addressable and can emit light independently of each other.

[0345] 41. The display according to any one of embodiments 23 to 37, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices and the third stacked blue light emitting devices, the first emitting unit and the second emitting unit are co-addressable and can emit light independently of each other.

[0346] 42. The display according to any one of embodiments 23 to 41, wherein

[0347] The first and second emitting units of the third stacked blue light emitting device are independently addressable and can emit light independently of each other; and

[0348] The first and second emitting units of the first stacked blue light emitting device and the second stacked blue light emitting device are co-addressable and can emit light independently of each other.

[0349] 43. The display according to any one of embodiments 23 to 42, wherein all of the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting device further include:

[0350] A third transmitting unit, the third transmitting unit including a third transmitting layer; and

[0351] The second charge generation layer; wherein

[0352] The third emitting unit and the second charge generating layer are disposed between the second emitting unit and the second electrode;

[0353] The second charge generation layer is disposed above the second emission unit;

[0354] The third emission unit is positioned above the second charge generation layer; and

[0355] The second electrode is positioned above the third transmitting unit; and

[0356] The third emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm, and the peak wavelength is defined as the third peak wavelength;

[0357] The third emitting unit emits blue light with a third chromaticity, the third chromaticity of which has chromaticity coordinates in the third CIE1931 (x,y) color space as (x3,y3); and

[0358] The third emitting layer includes organic light-emitting materials, quantum dot light-emitting materials, or perovskite light-emitting materials.

[0359] 44. The display according to embodiment 43, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices:

[0360] The third chromaticity is substantially the same as one of the first chromaticity and the second chromaticity; and

[0361] The third chromaticity is substantially different from either the first chromaticity or the second chromaticity.

[0362] 45. The display according to embodiment 43, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices:

[0363] The third transmitting unit shares an address with one of the first and second transmitting units and can emit light independently of either the first or second transmitting unit; and

[0364] The third transmitting unit is addressed independently of either the first or the second transmitting unit and can emit light independently of either the first or the second transmitting unit.

[0365] 46. ​​The display according to embodiment 43, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices:

[0366] The third transmitting unit shares an address with one of the first transmitting unit and the second transmitting unit and can transmit light without being independent of one of the first transmitting unit and the second transmitting unit;

[0367] The third transmitting unit is addressed independently of either the first or the second transmitting unit and can emit light independently of either the first or the second transmitting unit; wherein

[0368] The transmitting unit that is addressed together with the third transmitting unit has substantially the same chromaticity as the third transmitting unit; and

[0369] The transmitting unit addressed independently of the third transmitting unit has a chromaticity that is substantially different from that of the third transmitting unit.

[0370] 47. The display according to any one of embodiments 23 to 46, wherein the display is part of a consumer product.

[0371] Patent documents

[0372] EP 0423283 B1, Friend et al., “Electroluminescent Devices”

[0373] US 5707745 B1, Forrest et al., "Multicolor Organic Light Emitting Devices"

[0374] US 6303238 B1, Thompson et al., "OLEDs Doped with Phosphorescent Compounds"

[0375] US 7279704 B2, Walters et al., "Complexes with Tridentate Ligands"

[0376] US 9559151 B2, Hack et al., "OLED Display Architecture"

[0377] WO 2019 / 224546 A1

[0378] WO 2020 / 030042A1

[0379] US 2019 / 0043407 A1

[0380] EP 3188272 A1

[0381] Other literature

[0382] S. Adjokatse et al., “Broadly tunable metal halide perovskites for solid-state light-emission applications”, Material Today, Vol. 20, No. 8, pp. 413-424 (2017).

[0383] Forrest et al., “The stacked OLED (SOLED): a new type of organic device for achieving high-resolution full-color displays”, Synthetic Metals, Vol. 91, Nos. 1-3, pp. 9-13 (1997).

[0384] "Three-terminal RGB full-color OLED pixels for ultrahigh density displays," Nature Scientific Reports, Vol. 8, Article 9684 (2018).

[0385] Jung et al., “3-Stacked TopEmitting White OLED for High Resolution OLED TV”, SID Symposium Digest of Technical Papers 2016, Vol. 47, pp. 707-710 (2016).

[0386] Kathirgamanathan et al., “Electroluminescent Organic and Quantum Dot LEDs: The State of the Art,” Journal of Display Technology, Vol. 11, No. 5, pp. 480-493 (2015).

[0387] Kumar et al., “Efficient Blue Electroluminescence Using Quantum-Confined Two-Dimensional Perovskites”, ACS Nano, Vol. 10, pp. 9720-9729 (2016).

[0388] Soneira et al., “iPhone X OLED Display Technology Shoot-Out,” DisplayMate Technologies Corporation.

[0389] Takita et al., “Highly efficient deep-blue fluorescent dopant for achieving low-power OLED display satisfying BT.2020 chromaticity”, Journal of the SID 2018 (2018).

[0390] Uoyama et al., “Highly efficient organic light-emitting diodes from delayed fluorescence”, Nature, Vol. 492, pp. 234-238 (2012).

[0391] Wang et al., “Blue Quantum Dot Light-Emitting Diodes with High Electroluminescent Efficiency”, ACS Applied Materials & Interfaces, Vol. 9, pp. 38755-38760 (2017).

[0392] Zanoni et al., “Sky-blue OLED through PVK:[Ir(Fppy)2(Mepic)] active layer”, Synthetic Metals, Vol. 222, Part B, pp. 393-396 (2016).

Claims

1. A display, the display comprising: The first sub-pixel is configured to emit red light in the visible spectrum with a peak wavelength in the range of 580 nm to 780 nm; The second sub-pixel is configured to emit green light in the visible spectrum with a peak wavelength in the range of 500 nm to 580 nm; and The third sub-pixel is configured to emit blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm; in The first sub-pixel includes a first stacked blue light emitting device optically coupled to the red color conversion layer; The second sub-pixel includes a second stacked blue light emitting device optically coupled to the green color conversion layer; and The third sub-pixel includes a third stacked blue light emitting device; in All of the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting device include a stacked blue light emitting device, which includes: First electrode; Second electrode; A first launching unit, the first launching unit including a first launching layer; A second transmitting unit, the second transmitting unit including a second transmitting layer; and First charge generation layer; wherein The first transmitting unit, the second transmitting unit, and the first charge generating layer are all disposed between the first electrode and the second electrode; The first transmitting unit is positioned above the first electrode; The first charge generation layer is disposed above the first emission unit; The second transmitting unit is positioned above the first charge generation layer; The second electrode is positioned above the second transmitting unit; The first emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm, and the peak wavelength is defined as the first peak wavelength; The first emitting unit emits blue light with a first chromaticity, and the first chromaticity coordinates in the first CIE 1931 (x,y) color space are (x1, y1). The second emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm, and the peak wavelength is defined as the second peak wavelength; The second emitting unit emits blue light with a second chromaticity, and the second chromaticity's second CIE 1931 (x,y) color space chromaticity coordinates are (x2, y2); The second chromaticity is substantially different from the first chromaticity; and The first emitting layer and the second emitting layer include organic light-emitting materials, quantum dot light-emitting materials and / or perovskite light-emitting materials; The first stacked blue light emitting device, the second stacked blue light emitting device, and the third stacked blue light emitting device further include: A third transmitting unit, the third transmitting unit including a third transmitting layer; and The second charge generation layer; wherein The third emitting unit and the second charge generating layer are disposed between the second emitting unit and the second electrode; The second charge generation layer is disposed above the second emission unit; The third emission unit is positioned above the second charge generation layer; and The second electrode is positioned above the third transmitting unit; and The third emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 500 nm, and the peak wavelength is defined as the third peak wavelength; The third emitting unit emits blue light with a third chromaticity, the third chromaticity of which has chromaticity coordinates in the third CIE 1931 (x,y) color space as (x3, y3); and The third emitting layer comprises organic light-emitting materials, quantum dot light-emitting materials, or perovskite light-emitting materials; and For all of the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices: The third transmitting unit shares an address with one of the first and second transmitting units and can emit light independently of either the first or second transmitting unit; and The third transmitting unit is addressed independently of either the first or the second transmitting unit and can emit light independently of either the first or the second transmitting unit; wherein The transmitting unit that shares the same address as the third transmitting unit has the same chromaticity as the third transmitting unit; and The transmitting unit addressed independently of the third transmitting unit has a different chromaticity than the third transmitting unit.

2. The display according to claim 1, wherein For all the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices, the second chromaticity coordinates (x2, y2) are not contained within a first-order McAdam ellipse centered at the first chromaticity coordinates (x1, y1).

3. The display according to claim 1, wherein For all the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices, the second chromaticity coordinates (x2, y2) are not contained within a third-order McAdam ellipse centered at the first chromaticity coordinates (x1, y1).

4. The display according to any one of claims 1 to 3, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices and the third stacked blue light emitting devices, the second peak wavelength is at least 4 nm larger or at least 4 nm smaller than the first peak wavelength.

5. The display according to any one of claims 1 to 3, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices: The first CIE 1931 (x, y) color space chromaticity coordinates (x1, y1) can be converted to the first CIE 1976 (u', v') color space chromaticity coordinates (u1, v1); and The second CIE 1931 (x, y) color space chromaticity coordinates (x2, y2) can be converted to the second CIE 1976 (u', v') color space chromaticity coordinates (u2, v2); where The first chromaticity coordinates (u1, v1) and the second chromaticity coordinates (u2, v2) are sufficiently different such that the chromaticity difference defined by Δuv is 0.010 or greater.

6. The display according to any one of claims 1 to 5, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices and the third stacked blue light emitting devices, the first emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm; and the second emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm.

7. The display according to any one of claims 1 to 5, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices and the third stacked blue light emitting devices, the first emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 465 nm to 500 nm; and the second emitting unit emits blue light in the visible spectrum with a peak wavelength in the range of 380 nm to 465 nm.

8. The display according to any one of claims 1 to 5, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices and the third stacked blue light emitting devices, the first emitting unit emits blue light with a CIE 1931 y coordinate of 0.080 or less; and the second emitting unit emits blue light with a CIE 1931 y coordinate greater than 0.

080.

9. The display according to any one of claims 1 to 5, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices and the third stacked blue light emitting devices, the first emitting unit emits blue light with a CIE 1931 y coordinate greater than 0.080; and the second emitting unit emits blue light with a CIE 1931 y coordinate of 0.080 or less.

10. The display according to any one of claims 1 to 9, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices and the third stacked blue light emitting devices, the first emitting layer and the second emitting layer comprise an organic light-emitting material.

11. The display of claim 10, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices: At least one of the first emitting layer and the second emitting layer comprises a phosphorescent organic light-emitting material; and At least one of the first emitting layer and the second emitting layer comprises a fluorescent organic light-emitting material.

12. The display according to any one of claims 1 to 9, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices and the third stacked blue light emitting devices, the first emitting layer and the second emitting layer comprise quantum dot luminescent materials.

13. The display according to any one of claims 1 to 9, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices and the third stacked blue light emitting devices, the first emitting layer and the second emitting layer comprise a perovskite luminescent material.

14. The display according to any one of claims 1 to 9, wherein for all the first stacked blue light emitting devices, the second stacked blue light emitting devices, and the third stacked blue light emitting devices: The first emitting layer includes a first type of luminescent material, which is an organic luminescent material, a quantum dot luminescent material, or a perovskite luminescent material; The second emitting layer includes a second type of luminescent material, which is an organic luminescent material, a quantum dot luminescent material, or a perovskite luminescent material; and The second type of luminescent material is different from the first type of luminescent material.

15. The display according to any one of claims 1 to 14, wherein the first stacked blue light emitting device, the second stacked blue light emitting device and the third stacked blue light emitting device all have the same device architecture.

16. The display according to any one of claims 1 to 15, wherein the display is part of a consumer product.

Images