Display device

Abstract

The invention discloses a display device. The display device comprises a first sub-pixel and a second sub-pixel, the first sub-pixel comprises a first light-emitting element and a first pixel driving circuit driving the first light-emitting element, and the second sub-pixel comprises a second light-emitting element and a second pixel driving circuit driving the second light-emitting element. The second sub-pixel includes a second light emitting element, a second pixel driving circuit driving the second light emitting element, a third light emitting element, and a third pixel driving circuit driving the third light emitting element. When the target brightness of the first sub-pixel is included in the high brightness portion, the first pixel driving circuit controls the first light emitting element to emit light in a first control mode. The second pixel driving circuit controls the second light emitting element to emit light in a second control mode when the target brightness of the second sub-pixel is included in the high brightness portion. According to the display device, the light efficiency can be improved, and the power consumption can be reduced.

Description

[0001] Cross - reference to related applications

[0002] This application claims priority and the benefit of Korean Patent Application No. 10 - 2023 - 0185790, filed on December 19, 2023, the disclosure of which is incorporated herein by reference in its entirety. Technical field

[0003] This application relates to a display device. More specifically, this application relates to a display device using a light - emitting diode as a light source. Background art

[0004] An electroluminescent display device includes an inorganic light - emitting diode display device (hereinafter referred to as an "LED display device") in which an inorganic light - emitting diode (hereinafter referred to as an "LED") is provided.

[0005] Recently, as an example of an inorganic LED display device, a micro - LED display device in which micro - LEDs are provided in pixels has attracted attention as a next - generation display device. A micro - LED can be an inorganic LED having a size of 100 μm or less. The micro - LEDs can be manufactured in a separate semiconductor process, transferred to pixel positions on a substrate of a display panel of a display device, and provided in sub - pixels of each color. Summary of the invention

[0006] The present invention aims to provide a light - emitting diode display device in which a main light - emitting element and an auxiliary light - emitting element can emit light simultaneously. To achieve a target brightness, the brightness range is divided into a low - brightness part and a high - brightness part. The brightness is adjusted by controlling the magnitude of a data voltage in the low - brightness part, and the brightness is adjusted by changing a pulse width in the high - brightness part.

[0007] The object of this application is not limited to the above - mentioned object, and those skilled in the art will clearly understand other objects not mentioned from the following description.

[0008] The display device according to an embodiment of this application may include a first sub - pixel and a second sub - pixel. The first sub - pixel includes a first light - emitting element and a first pixel driving circuit for driving the first light - emitting element. The second sub - pixel includes a second light - emitting element, a second pixel driving circuit for driving the second light - emitting element, a third light - emitting element, and a third pixel driving circuit for driving the third light - emitting element. When the target brightness of the first sub - pixel is included in the high - brightness part, the first pixel driving circuit controls the first light - emitting element to emit light in a first control mode. When the target brightness of the second sub - pixel is included in the high - brightness part, the second pixel driving circuit controls the second light - emitting element to emit light in a second control mode.

[0009] In the first control mode, the amplitude of the data signal can be changed to adjust the brightness of the light-emitting element. In the second control mode, the amplitude of the data signal can be maintained.

[0010] The first sub-pixel and the second sub-pixel can achieve the same color.

[0011] When the target brightness of the first sub-pixel is included in the low brightness portion, the first pixel driving circuit controls the first light-emitting element to emit light in the first control mode. When the target brightness of the second sub-pixel is included in the low brightness portion, the second pixel driving circuit controls the second light-emitting element to emit light in the first control mode.

[0012] When the target brightness of the first sub-pixel is included in the medium brightness portion between the low brightness portion and the high brightness portion, the first pixel driving circuit controls the first light-emitting element to emit light in the second control mode and changes the light-emitting time of the first light-emitting element to adjust the brightness of the first light-emitting element. When the target brightness of the second sub-pixel is included in the medium brightness portion, the second pixel driving circuit controls the second light-emitting element to emit light in the second control mode and changes the light-emitting time of the second light-emitting element to adjust the brightness of the second light-emitting element.

[0013] At least one of the first light-emitting element and the second light-emitting element can have a maximum external quantum efficiency (EQE) in the medium brightness portion.

[0014] In the second control mode, the amplitude of the data signal corresponding to the maximum external quantum efficiency can be maintained.

[0015] When the target brightness of the second sub-pixel is included in the high brightness portion, the third pixel driving circuit can control the third light-emitting element to emit light.

[0016] The third pixel driving circuit can adjust the brightness of the third light-emitting element by changing the amplitude of the data signal.

[0017] The third pixel driving circuit can adjust the brightness of the third light-emitting element by changing the light-emitting time of the third light-emitting element.

[0018] Each of the first pixel driving circuit, the second pixel driving circuit, and the third pixel driving circuit can include a driving transistor and a light-emitting transistor. The driving transistor can provide a driving current for driving the light-emitting element according to the data signal, and the light-emitting transistor can apply the driving current to the light-emitting element according to the light-emitting control signal.

[0019] The data signal can include a pulse amplitude modulation signal in analog form, and the light-emitting control signal can include a pulse width modulation signal in digital form.

[0020] When the target brightness of the first sub-pixel is the maximum brightness in the low brightness portion, a light emission control signal with the minimum pulse width can be applied to the first pixel driving circuit. When the target brightness of the second sub-pixel is the maximum brightness in the low brightness portion, a light emission control signal with the minimum pulse width can be applied to the second pixel driving circuit.

[0021] When the target brightness of the first sub-pixel is the minimum brightness in the medium brightness portion, a light emission control signal with the minimum pulse width can be applied to the first pixel driving circuit. When the target brightness of the second sub-pixel is the minimum brightness in the medium brightness portion, a light emission control signal with the minimum pulse width can be applied to the second pixel driving circuit.

[0022] When the target brightness of the first sub-pixel is the maximum brightness in the medium brightness portion, a light emission control signal with the maximum pulse width can be applied to the first pixel driving circuit.

[0023] The light emission control signal with the maximum pulse width can include a duty ratio of 100%.

[0024] When the target brightness of the first sub-pixel is included in the high brightness portion, a light emission control signal with the maximum pulse width can be applied to the first pixel driving circuit.

[0025] When the target brightness of the second sub-pixel is the maximum brightness in the high brightness portion, a light emission control signal with the maximum pulse width can be applied to the second pixel driving circuit.

[0026] When the target brightness of the first sub-pixel is included in the medium brightness portion, the duty ratio of the light emission control signal applied to the first pixel driving circuit can increase as the target brightness of the first sub-pixel increases. When the target brightness of the second sub-pixel is included in the medium brightness portion, the duty ratio of the light emission control signal applied to the second pixel driving circuit can increase as the target brightness of the second sub-pixel increases.

[0027] The same light emission control signal can be applied to the first pixel driving circuit and the second pixel driving circuit.

[0028] In the high brightness portion, the average external quantum efficiency of the second light emitting element and the third light emitting element included in the second pixel driving circuit can be greater than the external quantum efficiency of the first light emitting element included in the first pixel driving circuit.

[0029] At least one of the first light emitting element, the second light emitting element, and the third light emitting element can include an inorganic light emitting diode (LED).

[0030] Specific details of other embodiments are included in the detailed description and the drawings. Description of the Drawings

[0031] The above and other objects, features, and advantages of the present invention will become more apparent to those of ordinary skill in the art by describing exemplary embodiments of the present invention in detail with reference to the accompanying drawings, wherein:

[0032] Figure 1 is a view showing a display device according to an embodiment of the present application;

[0033] Figure 2 is a view showing Figure 1 a partial enlarged view of region A of

[0034] Figure 3 is a view showing Figure 2 a partial enlarged view of the pixel region of

[0035] Figure 4 is a cross-sectional view taken along line I-I' in Figure 3 ;

[0036] Figure 5 is a cross-sectional view showing the structure of a light-emitting element;

[0037] Figure 6 is a graph showing the external quantum efficiency (hereinafter referred to as EQE) according to the luminance of the light-emitting element;

[0038] Figure 7 is a graph showing the luminance of the light-emitting element according to the voltage applied to the light-emitting element;

[0039] Figure 8 is a circuit diagram showing a pixel driving circuit connected to a light-emitting element according to an embodiment of the present application;

[0040] Figure 9 is a circuit diagram specifically showing a pixel driving circuit according to an embodiment of the present application;

[0041] Figure 10 is a graph showing the control mode according to the luminance portion in a single-chip sub-pixel;

[0042] Figure 11 is a graph showing the control mode according to the luminance portion in a dual-chip sub-pixel. Detailed Description of the Embodiments

[0043] Advantages and features of the present application and methods for achieving them will become clear by referring to the embodiments described in detail below with reference to the accompanying drawings. However, the present application is not limited to the embodiments disclosed below and will be embodied in various different forms. The present embodiments are provided only to make the disclosure of the present application complete and to fully inform those skilled in the art of the scope of the present application. The present application is defined only by the scope of the claims.

[0044] Since the shapes, sizes, proportions, angles, quantities, etc. disclosed in the drawings for illustrative purposes of the embodiments of the present application are exemplary, the present application is not limited to those shown. Additionally, when describing the present application, when it is determined that a detailed description of related known technologies may unnecessarily obscure the gist of the present application, its detailed description will be omitted.

[0045] When using terms such as "comprising", "having", "consisting of", etc. mentioned in the present application, unless "only" is used, other parts can be added. When a component is expressed in the singular, it includes the plural unless otherwise specifically stated.

[0046] When interpreting a component, unless otherwise specifically stated, it is interpreted as including a margin of error.

[0047] In the case of describing positional relationships, when the positional relationship between two parts is described as "on", "above", "below", or "next to", unless "immediately" or "directly" is used, one or more other parts can be located between the two parts.

[0048] When an element or layer is referred to as being on another element or layer, this includes being directly on another element or layer and also being on another element or layer in the case where yet another layer or element is interposed therebetween.

[0049] Additionally, terms such as "first", "second", etc. are used to describe various components, but the components are not limited by these terms. These terms are only used to distinguish one component from another. Therefore, within the technical spirit of the present application, the first component mentioned hereinafter can also be the second component.

[0050] Throughout the specification, the same reference numerals denote the same elements.

[0051] The dimensions and thicknesses of each component shown in the drawings are shown for illustrative purposes only, and the present application is not necessarily limited to the dimensions and thicknesses of the components shown.

[0052] Each feature of the various embodiments of the present application can be partially or fully combined or mixed, various types of technical intercommunication and driving are possible, each embodiment can be implemented independently of each other, or they can be implemented together in an associated relationship.

[0053] In a display device according to the present application, a pixel driving circuit may include a plurality of transistors. The transistors can be oxide TFTs containing an oxide semiconductor or LTPS TFTs including low-temperature polycrystalline silicon (LTPS).

[0054] A transistor is a three - electrode device including a gate, a source, and a drain. The source is the electrode that supplies carriers to the transistor. In a transistor, carriers start to flow out from the source. The drain is the electrode where carriers leave the transistor. In a transistor, carriers flow from the source to the drain.

[0055] In the case of an n - channel transistor, since the carriers are electrons, the source voltage is lower than the drain voltage, enabling electrons to flow from the source to the drain. In an n - channel transistor, current flows from the drain to the source. In the case of a p - channel transistor, since the carriers are holes, the source voltage is higher than the drain voltage, enabling holes to flow from the source to the drain. In a p - channel transistor, since holes flow from the source to the drain, current flows from the source to the drain. It should be noted that the source and drain of a transistor are not fixed. For example, the source and drain can change according to the applied voltage. Therefore, the present invention is not limited by the source and drain of the transistor. In the following description, the source and drain of the transistor are referred to as "the first electrode and the second electrode".

[0056] Hereinafter, various embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0057] Figure 1 is a view showing a display device according to an embodiment of the present application.

[0058] Reference Figure 1 , a display device 10 according to an embodiment of the present application may include a display panel having a display area AA or a screen on which a display image is provided, pixels PXL provided on the display panel, and a pixel driving circuit for driving the pixels PXL. The pixel driving circuit may be embedded in the display panel.

[0059] The display panel may include a display area AA for displaying an image and a non - display area NA for not displaying an image. Various lines and driving circuits may be installed in the non - display area NA, and a pad portion PAD for connecting to an integrated circuit, a printed circuit, etc. may be provided.

[0060] The pixels PXL provided in the display area AA may be formed by a plurality of light - emitting elements. The plurality of light - emitting elements may be inorganic light - emitting elements of micron size or inorganic light - emitting elements of nano size. The inorganic light - emitting elements may be grown on a silicon wafer and then bonded to the display panel through a transfer process.

[0061] The transfer process of the light - emitting elements may be performed for each predefined area. Figure 1It is shown that the display area AA is divided into 12 transfer areas ST, but the size or number of partitions of the transfer areas is not limited thereto. The transfer process can be performed sequentially or simultaneously in the first transfer area ST to the twelfth transfer area ST. In the transfer area ST, blue light-emitting elements, green light-emitting elements, and red light-emitting elements can be transferred sequentially, but not limited thereto.

[0062] In the non-display area NA, a data driving circuit or a gate driving circuit can be provided, and lines for supplying control signals for controlling the driving circuits can be provided. The control signals can include various timing signals, including a clock signal, an input data enable signal, and a synchronization signal. The control signals can be transmitted and received via the pad portion PAD.

[0063] Figure 2 is a partial enlarged view of Figure 1 area A shown.

[0064] Referring to Figure 2 , a display device according to an embodiment of the present application can include a display panel 100 and a pixel driving portion DR for controlling the display panel 100.

[0065] Each pixel provided on the display panel 100 can include a plurality of sub-pixels SP. The plurality of sub-pixels SP included in one pixel can include a plurality of main light-emitting elements 110 and auxiliary light-emitting elements 120 having different colors. The plurality of sub-pixels SP can be sequentially provided in a first direction (e.g., the X-axis direction) and a second direction (e.g., the Y-axis direction) intersecting the first direction. The plurality of light-emitting elements 200 of the same color can be provided in the sub-pixels SP of the display area AA. For example, the plurality of sub-pixels SP can include a red sub-pixel, a green sub-pixel, and a blue sub-pixel. The red sub-pixel can include a red main light-emitting element 110R and a red auxiliary light-emitting element 120R that emit light of a red wavelength. The green sub-pixel can include a green main light-emitting element 110G and a green auxiliary light-emitting element 120G that emit light of a green wavelength. The blue sub-pixel can include a blue main light-emitting element 110B and a blue auxiliary light-emitting element 120B that emit light of a blue wavelength.

[0066] One pixel PXL can include a plurality of sub-pixels SP. According to an embodiment, since one sub-pixel SP includes at least two light-emitting elements, the main light-emitting element 110 and the auxiliary light-emitting element 120 can be driven simultaneously. Therefore, the brightness of the sub-pixel SP can be up to twice the brightness of driving only one light-emitting element, and the brightness of the pixel PXL can be adjusted. However, the present application is not necessarily limited thereto, and one sub-pixel SP can include only one light-emitting element.

[0067] The pixel PXL can be driven by a pixel driving section DR. The pixel driving section DR can be a driving device manufactured using a metal-oxide-semiconductor field-effect transistor (MOSFET) manufacturing process. The pixel driving section DR can be a microdriver. The driving device can drive sub-pixels including a pixel driving circuit.

[0068] The pixel driving section DR can drive a plurality of pixels by receiving a driving voltage, an image signal (digital signal), a synchronization signal synchronized with the image signal, etc. and outputting an anode voltage and a cathode voltage of the light-emitting element 200. The driving voltage can be a high-potential voltage EVDD. The cathode voltage can be a low-potential voltage EVSS commonly applied to the pixels. The anode voltage can be a voltage corresponding to the pixel data value of the image signal. The pixel driving section DR can be disposed in the non-display area NA or below the display area AA. When the pixel driving section DR is disposed below the display area AA, one pixel driving section DR can be provided in each light-emitting area. The light-emitting area can include at least one pixel PXL. For example, the light-emitting area can include at least dozens or more pixels PXL.

[0069] In addition, a high-potential voltage can be applied to the circuits driving the respective light-emitting elements 110R, 110G, 110B, 120R, 120G, and 120B via signal lines 130 and 140. The signal lines 130 and 140 and the first electrode 212 can be formed by an integrated electrode pattern during an electrode patterning process.

[0070] As an example, the first signal line 130 can be connected to each of the first electrodes 212R of the red main light-emitting element 110R, the first electrodes 212G of the green main light-emitting element 110G, and the first electrodes 212B of the blue main light-emitting element 110B. The second signal line 140 can be connected to each of the first electrodes 212R' of the red auxiliary light-emitting element 120R, the first electrodes 212G' of the green auxiliary light-emitting element 120G, and the first electrodes 212B' of the blue auxiliary light-emitting element 120B. The number of the signal lines 130 and 140 can vary according to the number of light-emitting elements included in the sub-pixel SP. For example, when one sub-pixel includes only one light-emitting element, the number of the signal lines 130 and 140 can be reduced by half, but the present application is not limited thereto.

[0071] Figure 3 is a partial enlarged view of Figure 2 the pixel region. Figure 4 is a cross-sectional view taken along Figure 3 line I-I' in

[0072] Refer to Figures 2 to 4, a plurality of first electrodes 212 may be respectively disposed under the light-emitting elements 200 and may be selectively connected to a plurality of signal lines 130 and 140. A high-potential voltage may be applied to the pixel driving circuit 204 through the signal lines 130 and 140. The signal lines 130 and 140 and the first electrodes 212 may be formed of an integrated electrode pattern during an electrode patterning process. The first electrodes 212 may be anode electrodes provided for each column, and an anode voltage may be applied to the light-emitting elements 200 continuously arranged in a second direction (e.g., the Y-axis direction).

[0073] The second electrodes 214 may be cathode electrodes provided for each row, and a cathode voltage may be applied to the light-emitting elements 200 continuously arranged in a first direction (e.g., the X-axis direction) intersecting the second direction.

[0074] A plurality of second electrodes 214 may be arranged to be spaced apart from each other in the second direction (Y-axis direction). The plurality of second electrodes 214 may receive a cathode voltage through the contact electrodes 210. The plurality of second electrodes 214 may be electrically connected to the contact electrodes 210 respectively. However, the present application is not limited thereto, and the second electrodes 214 may not be divided into a plurality of second electrodes and may be formed as one electrode layer serving as a common electrode.

[0075] The display device according to an embodiment may include a plurality of first electrodes 212 and contact electrodes 210 disposed on a substrate 202, a plurality of light-emitting elements 200 disposed on the plurality of first electrodes 212, a first optical layer 222 disposed between the plurality of light-emitting elements 200, and second electrodes 214 disposed on the plurality of light-emitting elements 200.

[0076] The substrate 202 may be formed of flexible plastic. For example, the substrate 202 may be manufactured as a single-layer or multi-layer substrate of a material selected from polyimide, polyethylene terephthalate, polyethylene naphthalate, polyarylate, polysulfone, or cycloolefin copolymer, but is not limited thereto. For example, the substrate 202 may be a ceramic substrate or a glass substrate.

[0077] The pixel driving circuit 204 may be disposed in a display area AA on the substrate 202. The pixel driving circuit 204 may include a plurality of thin film transistors using amorphous silicon semiconductors, polycrystalline silicon semiconductors, or oxide semiconductors.

[0078] The pixel driving circuit 204 may include at least one driving thin film transistor, at least one switching thin film transistor, and at least one storage capacitor. When the pixel driving circuit 204 includes a plurality of thin film transistors, the pixel driving circuit 204 may be formed on the substrate 202 through a TFT manufacturing process. In an embodiment, as a general concept, the pixel driving circuit 204 may be a plurality of thin film transistors electrically connected to the light-emitting elements 200.

[0079] The buffer layer 206 covering the pixel driving circuit 204 may be disposed on the substrate 202. The buffer layer 206 may be formed of an organic insulating material, such as photosensitive acrylene or photosensitive polyimide, but is not limited thereto.

[0080] The buffer layer 206 may be provided as a plurality of layers formed by stacking inorganic insulating materials (such as silicon nitride (SiNx) or silicon oxide (SiO2)), and may be provided as a plurality of layers formed by stacking organic insulating materials and inorganic insulating materials.

[0081] The insulating layer 208 may be disposed on the buffer layer 206. The insulating layer 208 may be formed of an organic insulating material, such as photosensitive acrylene or photosensitive polyimide, but is not limited thereto.

[0082] The connection lines RT1 and RT2 may be disposed on the buffer layer 206. The connection lines RT1 and RT2 may be connected through the corresponding signal lines 130 and 140, or may be connected to the signal lines 130 and 140. The connection lines RT1 and RT2 may include a plurality of line patterns disposed on different layers, and one or more insulating layers are interposed between the line patterns. The line patterns disposed on different layers may be electrically connected through contact holes passing through the insulating layer.

[0083] A plurality of dam patterns 216 may be disposed on the insulating layer 208. At least one light-emitting element 200 may be disposed on each dam pattern 216. For example, the main light-emitting element 110 may be disposed on the first dam pattern 216, and the auxiliary light-emitting element 120 may be disposed on the second dam pattern 216.

[0084] The dam pattern 216 may be formed of an organic insulating material, such as photosensitive acrylene or photosensitive polyimide, but is not limited thereto. The dam pattern 216 may guide the attachment position of the light-emitting element 200 during the transfer process of the light-emitting element 200. The dam pattern 216 may be omitted.

[0085] The light-emitting elements 200 may be respectively mounted on the solder patterns 226 on the first electrodes 212. One pixel PXL may include light-emitting elements 200 of three colors. The red main light-emitting element 110R may be a red light-emitting element, the green main light-emitting element 110G may be a green light-emitting element, and the blue main light-emitting element 110B may be a blue light-emitting element. Two light-emitting elements of the same color may be mounted in each pixel.

[0086] The first optical layer 222 may cover the plurality of light-emitting elements 200 and the dam pattern 216. Accordingly, the first optical layer 222 may cover the spaces between the plurality of light-emitting elements 200 and between the plurality of dam patterns 216. The first optical layer 222 may extend in a first direction (e.g., the X-axis direction) and may be spaced apart in a second direction (e.g., the Y-axis direction) to separate between pixel rows.

[0087] The first optical layer 222 may include an organic insulating material in which fine metal particles such as titanium dioxide particles are dispersed. The fine metal particles dispersed in the first optical layer 222 may scatter and emit the light emitted from the plurality of light-emitting elements 200 to the outside.

[0088] The second electrode 214 may be disposed on the plurality of light-emitting elements 200. The second electrode 214 may be commonly connected to the plurality of pixels PXL. The second electrode 214 may be a thin electrode through which light is transmitted. The second electrode 214 is a transparent conductive oxide (TCO) and may be formed of, for example, indium tin oxide (ITO), but is not limited thereto.

[0089] The second electrode 214 may extend in a first direction (e.g., the X-axis direction) and may be spaced apart in a second direction (e.g., the Y-axis direction). The second electrode 214 may be disposed on the upper surface of the light-emitting element 200 and the upper surface of the first optical layer 222, may be in contact with the contact electrode 210, and may be disposed on the side surface of the first optical layer 222.

[0090] The second optical layer 224 may be formed of an organic insulating material surrounding the first optical layer 222. The second optical layer 224 may be disposed on the insulating layer 208 together with the first optical layer 222. The first optical layer 222 and the second optical layer 224 may include the same material (e.g., silicone). For example, the first optical layer 222 may be a silicone containing titanium oxide (TiOx), and the second optical layer 242 may be a silicone not containing titanium oxide (TiOx). However, the present application is not limited thereto, and the first optical layer 222 and the second optical layer 224 may be formed of the same material or may be formed of different materials.

[0091] The second optical layer 224 may cover at least a part of the second electrode 214. The upper surface of the second optical layer 224 and the upper surface of the second electrode 214 may form the same plane (e.g., the XY plane). The first optical layer 222 and the second optical layer 224 may be used as a planarization layer. Accordingly, since there is no step on the surface on which the black matrix 228 is formed, the pattern of the black matrix 228 may be easily formed on the first optical layer 222 and the second optical layer 224. However, the present application is not limited thereto, and the upper surfaces of the second optical layer 224 and the second electrode 214 may have different heights.

[0092] The black matrix 228 may be made of an organic insulating material added with a black pigment. The second electrode 214 may be in contact with the contact electrode 210 under the black matrix 228. Transmission holes 230 may be formed between the patterns of the black matrix 228, and the light emitted from the light-emitting element 200 is emitted to the outside through the transmission holes 230. The black matrix 228 may solve the problem that the light emitted from adjacent light-emitting elements 200 is mixed due to the first optical layer 222.

[0093] The cover layer 232 may be made of an organic insulating material that covers the black matrix 228 and the second electrode 214.

[0094] The contact electrode 210 may be electrically connected to the first connection line RT1 disposed thereunder, and the first connection line RT1 may be connected to the pixel driving circuit 204. The cathode voltage may be applied to the second electrode 214 through the contact electrode 210. The first electrode 212 may be electrically connected to the second connection line RT2.

[0095] The pixel driving circuit 204 may be disposed under the contact electrode 210. When the pixel driving circuit 204 is a driving device, a plurality of driving devices may be disposed in the display panel.

[0096] The passivation layer 220 may expose the contact electrode 210 to electrically connect the contact electrode 210 and the second electrode 214. In addition, the passivation layer 220 may isolate the signal lines 130 and 140 from the second electrode 214.

[0097] Figure 5 is a cross-sectional view of the structure showing the light-emitting element.

[0098] Reference Figure 5 , the connection portion 212a of the first electrode 212 may extend to one side surface of the bank pattern 216 and may be electrically connected to the connection line RT2 disposed on the buffer layer 206.

[0099] The first electrode 212, the connection portion 212a, the signal line, and / or the connection lines RT1 and RT2 may include a single or a plurality of metal layers of materials selected from titanium (Ti), molybdenum (Mo), and aluminum (Al). The first electrode 212, the connection portion 212a, the signal line, and / or the connection lines RT1 and RT2 may be formed in a multilayer structure including a first layer ML1, a second layer ML2, a third layer ML3, and a fourth layer ML4.

[0100] The first layer ML1 and the third layer ML3 may include titanium (Ti) or molybdenum (Mo). The second layer ML2 may include aluminum (Al). The fourth layer ML4 may include a transparent conductive oxide having good adhesion (e.g., to the solder pattern 226), corrosion resistance, and acid resistance, such as indium tin oxide (ITO) or indium zinc oxide (IZO).

[0101] The first layer ML1, the second layer ML2, the third layer ML3, and the fourth layer ML4 can be deposited in sequence and then patterned by performing a photolithography process and an etching process.

[0102] The passivation layer 220 can be disposed on the first electrode 212 and the signal line and expose the solder pattern 226.

[0103] The light-emitting element 200 can include a first conductive semiconductor layer 236, an active layer 238, and a second conductive semiconductor layer 240. The first driving electrode 234 can be disposed under the first conductive semiconductor layer 236, and the second driving electrode 242 can be disposed above the second conductive semiconductor layer 240.

[0104] The light-emitting element 200 can be formed on a silicon wafer using a metalorganic chemical vapor deposition (MOCVD) method, a chemical vapor deposition (CVD) method, a plasma-enhanced chemical vapor deposition (PECVD) method, a molecular beam epitaxy (MBE) method, a hydride vapor phase epitaxy (HVPE) method, a sputtering method, or the like.

[0105] The first conductive semiconductor layer 236 can be implemented with a compound semiconductor such as a group III-V or II-VI compound semiconductor and can be doped with a first dopant. The first conductive semiconductor layer 236 can be composed of a semiconductor material having a composition formula of Al x1 In y1 Ga (1-x1-y1) N (0≤x1≤1, 0≤y1≤1, 0≤x1 + y1≤1) or a material selected from InAlGaN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP, but is not limited thereto. When the first dopant is an n-type dopant such as Si, Ge, Sn, Se, Te, etc., the first conductive semiconductor layer 236 can be an n-type nitride semiconductor layer. However, when the first dopant is a p-type dopant, the first conductive semiconductor layer 236 can be a p-type nitride semiconductor layer.

[0106] The active layer 238 is a layer where electrons (or holes) injected from the first conductive semiconductor layer 236 meet holes (or electrons) injected from the second conductive semiconductor layer 240. When electrons and holes recombine, the active layer 238 can transition to a lower energy level and generate light with a corresponding wavelength.

[0107] The active layer 238 may have any one of a single well structure, a multi-well structure, a single quantum well structure, a multi-quantum well (MQW) structure, a quantum dot structure, or a quantum wire structure, and the structure of the active layer 238 is not limited thereto. The active layer 238 can generate light in the visible wavelength range. As an example, the active layer 238 can output light in the wavelength range of any one of blue, green, and red.

[0108] The second conductive semiconductor layer 240 may be disposed on the active layer 238. The second conductive semiconductor layer 240 can be implemented with a compound semiconductor such as a group III-V or II-VI compound semiconductor, and the second conductive semiconductor layer 240 can be doped with a second dopant. The second conductive semiconductor layer 240 may be formed of a semiconductor material having a composition formula of In x2 Al y2 Ga 1-x2-y2 N (0 ≤ x2 ≤ 1, 0 ≤ y2 ≤ 1, 0 ≤ x2 + y2 ≤ 1) or a material selected from AlInN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP. When the second dopant is a p-type dopant such as Mg, Zn, Ca, Sr, or Ba, the second conductive semiconductor layer 240 doped with the second dopant can be a p-type semiconductor layer. When the second dopant is an n-type dopant, the second conductive semiconductor layer 240 can be an n-type nitride semiconductor layer.

[0109] The reflective layer 244 may be disposed below the light-emitting element 200. The reflective layer 244 may have a structure in which a reflective material is dispersed in a resin layer, but is not limited thereto. The reflective layer 244 can be manufactured in various structures. The light emitted from the active layer 238 is reflected upward due to the reflective layer 244, thereby increasing the light extraction efficiency.

[0110] Although this embodiment is described as a vertical structure in which the driving electrodes 234 and 242 are disposed above and below the light-emitting member, in addition to the vertical structure, the light-emitting element may also have a lateral structure or a flip-chip structure.

[0111] The pixel driving circuit 204 can apply an anode voltage to the main light-emitting element 110 and the auxiliary light-emitting element 120 via the second connection line RT2. The pixel driving circuit 204 can apply a cathode voltage to the main light-emitting element 110 and the auxiliary light-emitting element 120 via the first connection line RT1 and the second electrode 214.

[0112] The pixel driving circuit 204 can control the brightness by driving only one of the main light-emitting element 110 or the auxiliary light-emitting element 120. The pixel driving circuit 204 can control the brightness by driving both the main light-emitting element 110 and the auxiliary light-emitting element 120. In an embodiment, the pixel driving circuit 204 can control the brightness by driving the main light-emitting element 110 and the auxiliary light-emitting element 120 simultaneously. When the main light-emitting element 110 dims, the pixel driving circuit 204 can control the brightness by driving only the auxiliary light-emitting element 120.

[0113] Figure 6 is a graph showing the external quantum efficiency (hereinafter referred to as EQE) according to the brightness of the light-emitting element. Figure 7 is a graph showing the brightness of the light-emitting element according to the voltage supplied to the light-emitting element.

[0114] Reference Figure 6 , the EQE of each light-emitting element emitting red (R), green (G), and blue (B) light can have a maximum value. Each light-emitting element can have the maximum luminous efficiency at the maximum value of the EQE.

[0115] Reference Figure 7 , the brightness as a function of the voltage supplied to the light-emitting element can include a low brightness portion (a) and a point (or portion) (b) where the brightness increases and the slope of the curve changes rapidly. The point (or portion) (b) where the slope of the curve changes rapidly is the point of the maximum luminous efficiency of the light-emitting element and is the point having the maximum value of the EQE of the light-emitting element.

[0116] Figure 8 is a circuit diagram showing a pixel driving circuit connected to a light-emitting element according to an embodiment of the present application.

[0117] Reference Figure 8 , the pixel driving circuit 204 can include a driving transistor D-Tr and a light-emitting transistor E-Tr. The pixel driving circuit 204 can also include a plurality of power supply lines, a plurality of scan lines, a reference voltage line, a data voltage line, and a light emission control line.

[0118] The driving transistor D-Tr and the light-emitting transistor E-Tr can be implemented as n-channel TFTs. The n-channel TFT can be turned on in response to a high gate voltage and turned off in response to a low gate voltage. The p-channel TFT can be turned on in response to a low gate voltage and turned off in response to a high gate voltage. Hereinafter, it is assumed that the shown driving transistor D-Tr and light-emitting transistor E-Tr are n-channel TFTs for explanation, but this is an example, and the driving transistor D-Tr or the light-emitting transistor E-Tr can also be implemented as a p-channel TFT.

[0119] The driving transistor D-Tr can be disposed between the light-emitting transistor E-Tr and the line to which the high-potential voltage EVDD is applied. The driving transistor D-Tr can regulate the current I flowing into the light-emitting element 200 in response to the gate-source voltage Vgs LED to drive the light-emitting element 200. In the case of an n-channel transistor, since the carriers are electrons, the gate electrode to which the data signal Vdata is applied can be the positive electrode, and the source electrode can be the negative electrode. The driving transistor D-Tr can include a first electrode (e.g., the source electrode) connected to the second electrode of the light-emitting transistor E-Tr, a second electrode (e.g., the drain electrode) to which the high-potential voltage EVDD is applied, and a gate electrode to which the data signal Vdata is applied.

[0120] The light-emitting transistor E-Tr can be disposed between the driving transistor D-Tr and the light-emitting element 200. The light-emitting transistor E-Tr can switch the current I flowing to the light-emitting element 200 with a set pulse width LED . The light-emitting transistor E-Tr can include a first electrode (e.g., the source electrode) connected to the light-emitting element 200, a second electrode (e.g., the drain electrode) connected to the first electrode of the driving transistor D-Tr, and a gate electrode to which the light-emitting control signal EM is applied.

[0121] The pixel driving circuit 204 can cause the light-emitting element 200 to emit light in a first control mode or a second control mode. The light-emitting element 200 can be caused to emit light by controlling it in the first control mode or the second control mode.

[0122] When the light-emitting element 200 is controlled in the first control mode, the brightness of the light-emitting element 200 can be controlled by the analog-form data signal Vdata applied to the gate electrode of the driving transistor D-Tr. Since the current I flowing into the light-emitting element 200 can be regulated according to the gate-source voltage Vgs of the driving transistor D-Tr LED of the amount, the brightness of the light-emitting element 200 controlled in the first control mode can be regulated by the data signal Vdata applied to the gate electrode.

[0123] When the light-emitting element 200 is controlled in the second control mode, the brightness of the light-emitting element 200 can be controlled by the digital-form light-emitting control signal EM applied to the gate electrode of the light-emitting transistor E-Tr. For example, the light-emitting control signal EM can be a signal whose pulse width is modulated (pulse width modulation (PWM)). The digital-form light-emitting control signal EM can include a duty ratio as a PWM signal. Since the current I applied to the light-emitting element 200 can be regulated by adjusting the duty ratio of the digital-form light-emitting control signal EM LED of the amount, the brightness of the light-emitting element 200 can be controlled by the light-emitting control signal EM.

[0124] Refer to the above Figure 7 and 8 , the light-emitting element 200 can emit light in the (a) part in the first control mode and can emit light in the (b) point (or part) in the second control mode.

[0125] Figure 9 is a circuit diagram specifically showing a pixel driving circuit according to an embodiment of the present application.

[0126] Refer to Figure 9 , the display panel may include a first pixel PXL1 and a second pixel PXL2. The first pixel PXL1 may include a 1-1 sub-pixel PXL1_SP1. The second pixel PXL2 may include a 2-1 sub-pixel PXL2_SP1. The 1-1 sub-pixel PXL1_SP1 included in the first pixel PXL1 and the 2-1 sub-pixel PXL2_SP1 included in the second pixel PXL2 may achieve the same color. The color achieved in the sub-pixels PXL1_SP1 and PXL2_SP1 may be any one selected from the group consisting of red, green, and blue.

[0127] Each of the sub-pixels PXL1_SP1 and PXL2_SP1 may include a single or multiple pixel driving circuits. As shown in the figure, both the 1-1 sub-pixel PXL1_SP1 and the 2-1 sub-pixel PXL2_SP1 include multiple pixel driving circuits, but it is not limited thereto.

[0128] When the sub-pixel includes a single pixel driving circuit, the transfer may not be executed normally, and the pixel driving circuit may not be deposited normally.

[0129] When the sub-pixels PXL1_SP1 and PXL2_SP1 include multiple pixel driving circuits, it may not be considered that all of the multiple pixel driving circuits drive the light-emitting element operating normally. For example, the 1-1 sub-pixel PXL1_SP1 may include multiple pixel driving circuits, where one pixel driving circuit may be the pixel driving circuit for driving the light-emitting element 200 operating normally, and another pixel driving circuit may be the pixel driving circuit for driving the light-emitting element 200 operating abnormally. The light-emitting element 200 operating abnormally is a defective element that cannot emit light even when driving power is applied, and is marked with "X" in the figure.

[0130] The 1-1 sub-pixel PXL1_SP1 may include a single light-emitting element that is transferred and operates normally. The 1-1 sub-pixel PXL1_SP1 may be a single-chip sub-pixel.

[0131] The 2-1 sub-pixel PXL2_SP1 may include a dual light-emitting element that transfers and operates normally. The 2-1 sub-pixel PXL2_SP1 may be a dual-chip sub-pixel. One of the plurality of pixel driving circuits may drive the main light-emitting element 200, and the other may drive the auxiliary light-emitting element 200.

[0132] The above terms "single" or "dual" do not distinguish the number of pixel driving circuits deposited, but refer to the number of LED chips that transfer and deposit normally and furthermore operate normally.

[0133] The plurality of pixel driving circuits may be connected to each other through a plurality of data lines Vdata_S, Vdata_D1, Vdata_D2, a plurality of driving power supply lines DPL_S, DPL_D1, DPL_D2, a plurality of common power supply lines CPL_m, CPL_r, a plurality of light-emitting control lines EM_m, EM_r, and a plurality of gate lines SCAN_m, SCAN_r.

[0134] The plurality of pixel driving circuits may include a plurality of switching elements S_Tr, D_Tr, E_Tr. The plurality of switching elements S_Tr, D_Tr, E_Tr shown are implemented as n-channel TFTs, but this is an example, and the plurality of switching elements S_Tr, D_Tr, E_Tr may be implemented as p-channel TFTs. The plurality of electrodes (e.g., the first electrode or the second electrode) included in each switching element may be the source electrode or the drain electrode as described above, but may also be the drain electrode or the source electrode.

[0135] Each of the plurality of pixel driving circuits may include a switching transistor S_Tr that applies a data signal Vdata to a driving transistor D_Tr according to a gate signal, a driving transistor D_Tr that provides a driving current according to the data signal Vdata applied by the switching transistor S_Tr, a light-emitting transistor E_Tr that determines the light-emitting timing of the light-emitting element 200 according to a light-emitting control signal EM, and the light-emitting element 200. Each of the plurality of pixel driving circuits may further include a storage capacitor Cst that conducts the driving transistor D_Tr by storing a voltage corresponding to the data signal Vdata.

[0136] Multiple data lines Vdata_S, Vdata_D1, Vdata_D2 may include a single data line Vdata_S that applies a data signal Vdata to a 1-1 sub-pixel PXL1_SP1 including one normally operating light-emitting element, and double data lines Vdata_D1 and Vdata_D2 that apply the data signal Vdata to a 2-1 sub-pixel PXL2_SP1 including multiple normally operating light-emitting elements. The double data lines Vdata_D1 and Vdata_D2 may include a first double data line Vdata_D1 that provides the data signal Vdata to drive the main light-emitting element 200 and a second double data line Vdata_D2 that provides the data signal Vdata to drive the auxiliary light-emitting element 200.

[0137] The single data line Vdata_S, the first double data line Vdata_D1, and the second double data line Vdata_D2 may all operate independently of each other. For example, the data voltage applied through the single data line Vdata_S, the data voltage applied through the first double data line Vdata_D1, and the data voltage applied through the second double data line Vdata_D2 may be different.

[0138] Multiple driving power lines DPL_S, DPL_D1, DPL_D2 may include a single driving power line DPL_S that applies driving power to a 1-1 sub-pixel PXL1_SP1 including one normally operating light-emitting element, and double driving power lines DPL_D1 and DPL_D2 that apply driving power to a 2-1 sub-pixel PXL2_SP1 including multiple normally operating light-emitting elements. The double driving power lines DPL_D1 and DPL_D2 may include a first double driving power line DPL_D1 that applies driving power to the main light-emitting element 200 and a second double driving power line DPL_D2 that applies driving power to the auxiliary light-emitting element 200.

[0139] Multiple common power lines CPL_m, CPL_r may include a first main common power line CPL_m1 that supplies power to the main light-emitting element 200 of the 1-1 sub-pixel PXL1_SP1, a second main common power line CPL_m2 that supplies power to the main light-emitting element 200 of the 2-1 sub-pixel PXL2_SP1, and a second auxiliary common power line CPL_r2 that supplies power to the auxiliary light-emitting element 200 of the 2-1 sub-pixel PXL2_SP1.

[0140] The first main common power line CPL_m1 and the second main common power line CPL_m2 can be connected to or separated from each other. For example, when the 1-1 sub-pixel PXL1_SP1 and the 2-1 sub-pixel PXL2_SP1 share a gate line with each other and are arranged in the same pixel row, the first main common power line CPL_m1 and the second main common power line CPL_m2 can be connected to each other. When the 1-1 sub-pixel PXL1_SP1 and the 2-1 sub-pixel PXL2_SP1 have different gate lines and are arranged in different pixel rows, the first main common power line CPL_m1 and the second main common power line CPL_m2 can be separated from each other.

[0141] Multiple emission control lines EM_m, EM_r may include a first main emission control line EM_m1 that supplies an emission control signal EM to an emission transistor E_Tr connected to a main light-emitting element 200 of the 1-1 sub-pixel PXL1_SP1, a second main emission control line EM_m2 that supplies the emission control signal EM to an emission transistor E_Tr connected to a main light-emitting element 200 of the 2-1 sub-pixel PXL2_SP1, and a second auxiliary emission control line EM_r2 that supplies the emission control signal EM to an emission transistor E_Tr connected to an auxiliary light-emitting element 200 of the 2-1 sub-pixel PXL2_SP1.

[0142] The first main emission control line EM_m1 and the second main emission control line EM_m2 can be connected to or separated from each other. For example, when the 1-1 sub-pixel PXL1_SP1 and the 2-1 sub-pixel PXL2_SP1 share a gate line with each other and are arranged in the same pixel row, the first main emission control line EM_m1 and the second main emission control line EM_m2 can be connected to each other. When the 1-1 sub-pixel PXL1_SP1 and the 2-1 sub-pixel PXL2_SP1 have different gate lines and are arranged in different pixel rows, the first main emission control line EM_m1 and the second main emission control line EM_m2 can be separated from each other.

[0143] When the first main emission control line EM_m1 and the second main emission control line EM_m2 are connected to each other, the emission transistors E_Tr connected to the main light-emitting element 200 of the 1-1 sub-pixel PXL1_SP1 and sharing the main emission control line EM_m and the emission transistor E_Tr connected to the main light-emitting element 200 of the 2-1 sub-pixel PXL2_SP1 can operate in correlation with each other. For example, the duty ratio of the emission control signal EM supplied to the first main emission control line EM_m1 and the duty ratio of the emission control signal EM supplied to the second main emission control line EM_m2 can be substantially the same.

[0144] The main light emission control line EM_m and the auxiliary light emission control line EM_r can operate independently of each other. For example, the duty ratio of the light emission control signal EM supplied to the main light emission control line EM_m and the duty ratio of the light emission control signal EM supplied to the auxiliary light emission control line EM_r can be different.

[0145] The independent operation of the main light emission control line EM_m and the auxiliary light emission control line EM_r can be interpreted as the anode electrodes of the light emitting elements 200 being formed independently of each other. Since the anode electrodes are formed independently, the voltages supplied to the anode electrodes in the main light emitting element 200 and the auxiliary light emitting element 200 can be independent.

[0146] The plurality of gate lines SCAN_m, SCAN_r may include a first main gate line SCAN_m1 that provides a gate signal to drive the main light emitting element 200 of the 1-1 sub-pixel PXL1_SP1, a second main gate line SCAN_m2 that provides a gate signal to drive the main light emitting element 200 of the 2-1 sub-pixel PXL2_SP1, and an auxiliary gate line SCAN_r that provides a gate signal to drive the auxiliary light emitting element 200 of the 2-1 sub-pixel PXL2_SP1.

[0147] The first main gate line SCAN_m1 and the second main gate line SCAN_m2 may be connected to or separated from each other. For example, when the 1-1 sub-pixel PXL1_SP1 and the 2-1 sub-pixel PXL2_SP1 share a gate line with each other and are provided on the same pixel row, the first main gate line SCAN_m1 and the second main gate line SCAN_m2 may be connected to each other. When the 1-1 sub-pixel PXL1_SP1 and the 2-1 sub-pixel PXL2_SP1 have different gate lines and are provided on different pixel rows, the first main gate line SCAN_m1 and the second main gate line SCAN_m2 may be separated from each other.

[0148] The switching transistor S_Tr included in each pixel driving circuit may supply a data voltage to the driving transistor D_Tr or the storage capacitor Cst according to a gate signal. The switching transistor S_Tr may include a gate electrode connected to the gate lines SCAN_m and SCAN_r to which the gate signal is applied, a first electrode connected to the data lines Vdata_S, Vdata_D1, Vdata_D2 to which the data signal Vdata is applied, and a second electrode connected to the gate electrode of the driving transistor D_Tr.

[0149] The driving transistor D_Tr included in each pixel driving circuit can supply a driving current to the light-emitting element 200 according to the voltage provided by the switching transistor S_Tr or the voltage provided by the storage capacitor Cst. The driving transistor D_Tr can include a gate electrode to which a data signal Vdata is applied by being connected to the second electrode of the switching transistor S_Tr, a first electrode to which a driving power is applied, and a second electrode connected to the first electrode (or a light-emitting node) of the light-emitting transistor E_Tr.

[0150] The conduction timing of the light-emitting transistor E_Tr included in each pixel driving circuit can be determined by the time of the pulse width of the signal provided according to the light-emitting control lines EM_m and EM_r. The turned-on light-emitting transistor E_Tr can supply the driving current applied by the driving transistor D_Tr to the light-emitting element 200. The time according to the pulse width can be determined by the duty ratio of the signal provided by the light-emitting control line. The pulse width of the signal provided by the light-emitting control lines EM_m and EM_r can be determined by a preset duty ratio. The light-emitting transistor E_Tr can include a gate electrode to which a light-emitting control signal EM is applied, a first electrode connected to the second electrode (or a light-emitting node) of the driving transistor D_Tr, and a second electrode connected to the light-emitting element 200.

[0151] The data signal Vdata supplied to each driving transistor D_Tr can be a pulse amplitude modulation (PAM) signal. The voltage corresponding to the data signal Vdata supplied to each driving transistor D_Tr can be the data signal Vdata in the above analog form.

[0152] The light-emitting control signal EM supplied to each light-emitting transistor E_Tr can be a pulse width modulation (PWM) signal. The voltage corresponding to the light-emitting control signal EM supplied to each light-emitting transistor E_Tr can be the light-emitting control signal EM in the above digital form.

[0153] When controlling the light-emitting element 200 in the first control mode, the brightness can be adjusted by the data signal Vdata in the analog form, and when controlling the light-emitting element 200 in the second control mode, the brightness can be adjusted by the light-emitting control signal EM in the digital form.

[0154] The 1-1 sub-pixel PXL1_SP1, which is a single-chip sub-pixel including only the main light-emitting element 200, can be driven in the first control mode, the second control mode, and the first control mode in the direction of increasing the target brightness value.

[0155] The 2-1 sub-pixel PXL2_SP1, which is a dual-chip sub-pixel including the main light-emitting element 200 and the auxiliary light-emitting element 200, can be driven in a first control mode, a second control mode, and a third control mode in the direction of increasing the target brightness value.

[0156] The brightness range of the light-emitting element can be divided into a first brightness portion LB1, a second brightness portion LB2, and a third brightness portion LB3 in ascending order from the minimum to the maximum. The brightness value of the second brightness portion LB2 can be greater than the brightness value of the first brightness portion LB1. The brightness value of the third brightness portion LB3 can be greater than the brightness value of the second brightness portion LB2.

[0157] In the first brightness portion LB1, the 1-1 sub-pixel PXL1_SP1, which is a single-chip sub-pixel, can be driven in the first control mode, and the 2-1 sub-pixel PXL2_SP1, which is a dual-chip sub-pixel, can be driven in the first control mode. In the second brightness portion LB2, the 1-1 sub-pixel PXL1_SP1, which is a single-chip sub-pixel, can be driven in the second control mode, and the 2-1 sub-pixel PXL2_SP1, which is a dual-chip sub-pixel, can be driven in the second control mode. In the third brightness portion LB3, the 1-1 sub-pixel PXL1_SP1, which is a single-chip sub-pixel, can be driven in the first control mode, and the 2-1 sub-pixel PXL2_SP1, which is a dual-chip sub-pixel, can be driven in the second control mode.

[0158] Figure 10 It is a graph showing the control mode according to the brightness portion in the single-chip sub-pixel. Figure 11 It is a graph showing the control mode according to the brightness portion in the dual-chip sub-pixel.

[0159] Reference Figure 7 、 9 And 10, the target brightness in part (a) can include the first brightness portion LB1. In part (a), the brightness of the light-emitting element 200 can be controlled in the first control mode. In part (a), when a larger current is applied to the driving transistor D_Tr, a greater brightness can be achieved. At the point with the maximum brightness in part (a), a light-emitting control signal EM with the minimum pulse width can be applied.

[0160] The target brightness of part (b) may include a second brightness portion LB2. In part (b), the brightness of the light-emitting element 200 may be controlled in a second control mode. In part (b), when a signal with a wider pulse width (e.g., a signal with a larger duty ratio) is applied to the light-emitting transistor E_Tr, a greater brightness can be achieved. At the point with the minimum brightness value in part (b), a light-emitting control signal EM with the minimum pulse width may be applied. At the point with the maximum brightness value in part (b), a light-emitting control signal EM with the maximum pulse width may be applied. The maximum pulse width may be a signal with a duty ratio of 100%.

[0161] The target brightness of part (c) may include a third brightness portion LB3. In part (c), the brightness of the light-emitting element 200 may be controlled in a first control mode. In part (c), when the driving transistor D_Tr applies a larger current, a greater brightness can be achieved. In part (c), the EQE of the light-emitting element 200 may not be the maximum value. In part (c), a data voltage higher than the data voltage provided in part (a) may be applied to the main light-emitting element 200 of the 1-1 sub-pixel PXL1_SP1 with an efficiency less than the maximum EQE.

[0162] Reference Figure 7 、 9 and 11, the target brightness of part (a) may include a first brightness portion LB1. In part (a), the brightness of the light-emitting element 200 may be controlled in a first control mode. In part (a), when the driving transistor D_Tr applies a larger current, a greater brightness can be achieved.

[0163] The target brightness of part (b) may include a second brightness portion LB2 and a third brightness portion LB3. The target brightness of part (b) may include the target brightness of part (b) as described above Figure 10 and the target brightness of part (c). In part (b), the brightness of the light-emitting element 200 may be controlled in a second control mode. In part (b), when a signal with a wider pulse width (e.g., a signal with a larger duty ratio) is applied to the light-emitting transistor E_Tr, a greater brightness can be achieved. At the point with the minimum brightness value in part (b), a light-emitting control signal EM with the minimum pulse width may be applied. At the point with the maximum brightness value in part (b), a light-emitting control signal EM with the maximum pulse width may be applied. The maximum pulse width may be a signal with a duty ratio of 100%.

[0164] Reference Figures 9 to 11, the display device according to the embodiment may include a 1-1 sub-pixel PXL1_SP1 and a 2-1 sub-pixel PXL2_SP1. The 1-1 sub-pixel PXL1_SP1 is a single-chip sub-pixel including a main light-emitting element 200, and the 2-1 sub-pixel PXL2_SP1 is a dual-chip sub-pixel including a main light-emitting element 200 and an auxiliary light-emitting element 200.

[0165] In the first brightness portion LB1, the main light-emitting element 200 of the 1-1 sub-pixel PXL1_SP1 may be controlled by a single data line Vdata_S, the main light-emitting element 200 of the 2-1 sub-pixel PXL2_SP1 may be controlled by a first dual data line Vdata_D1, and the auxiliary light-emitting element 200 of the 2-1 sub-pixel PXL2_SP1 may be controlled by a second dual data line Vdata_D2. In the first brightness portion LB1, the magnitude of the data voltage provided by the single data line Vdata_S, the first dual data line Vdata_D1, or the second dual data line Vdata_D2 may be adjusted to increase the brightness of the 1-1 sub-pixel PXL1_SP1 and / or the 2-1 sub-pixel PXL2_SP1. Alternatively, the duty ratio of the light-emitting control signal provided by the auxiliary light-emitting control line EM_r may be adjusted to increase the brightness of the 2-1 sub-pixel PXL2_SP1.

[0166] The data voltage value required to achieve the maximum target brightness in the first brightness portion LB1 when the 1-1 sub-pixel PXL1_SP1 is controlled in the first control mode and the data voltage value required to achieve the maximum target brightness in the first brightness portion LB1 when the 2-1 sub-pixel PXL2_SP1 is controlled in the first control mode may be substantially the same. However, the present application is not limited thereto. In the 2-1 sub-pixel PXL2_SP1, in addition to the first dual data line Vdata_D1, the maximum target brightness in the first brightness portion LB1 may also be achieved by providing a data voltage to the second dual data line Vdata_D2. In this case, the sum of the data voltage provided to the first dual data line Vdata_D1 and the data voltage provided to the second dual data line Vdata_D2 may be different from the data voltage provided to the single data line Vdata_S.

[0167] In the second brightness portion LB2, the data voltage corresponding to the maximum EQE may be provided to the main light-emitting element 200 of the 1-1 sub-pixel PXL1_SP1, which is a single-chip sub-pixel. In the second brightness portion LB2, the duty ratio of the main light-emitting control line EM_m may be adjusted to increase the brightness of the main light-emitting element 200 of the 1-1 sub-pixel PXL1_SP1, which is a single-chip sub-pixel. In the second brightness portion LB2, the brightness of the main light-emitting element 200 of the 1-1 sub-pixel PXL1_SP1, which is a single-chip sub-pixel, may be controlled by the main light-emitting control line EM_m.

[0168] In the second brightness section LB2, the data voltage corresponding to the maximum EQE can be provided to the main light-emitting element 200 of the 2-1 sub-pixel PXL2_SP1 which is a dual-chip sub-pixel. In the second brightness section LB2, the duty ratio of the main light-emitting control line EM_m can be adjusted to increase the brightness of the main light-emitting element 200 of the 2-1 sub-pixel PXL2_SP1. In the second brightness section LB2, the main light-emitting element 200 of the 2-1 sub-pixel PXL2_SP1 which is a dual-chip sub-pixel can be controlled by the main light-emitting control line EM_m, and the main light-emitting control line EM_m simultaneously controls the brightness of the main light-emitting element 200 of the 1-1 sub-pixel PXL1_SP1 which is a single-chip sub-pixel.

[0169] In the second brightness section LB2, the data voltage can be provided through the second dual data line Vdata_D2, or the light-emitting control signal EM provided by the auxiliary light-emitting control line EM_r operating independently of the main light-emitting control line EM_m can be provided to the auxiliary light-emitting element 200 of the 2-1 sub-pixel PXL2_SP1 which is a dual-chip sub-pixel. In the second brightness section LB2, the magnitude of the data voltage provided by the second dual data line Vdata_D2 can be adjusted to increase the brightness of the auxiliary light-emitting element 200 of the 2-1 sub-pixel PXL2_SP1 which is a dual-chip sub-pixel. Alternatively, the duty ratio of the light-emitting control signal provided by the auxiliary light-emitting control line EM_r can be adjusted to increase the brightness of the auxiliary light-emitting element 200 of the 2-1 sub-pixel PXL2_SP1 which is a dual chip.

[0170] In the second brightness section LB2, the brightness of the 2-1 sub-pixel PXL2_SP1 which is a dual-chip sub-pixel can be controlled by the main light-emitting control line EM_m, the auxiliary light-emitting control line EM_r, and the second dual data line Vdata_D2.

[0171] In the third brightness section LB3, the light-emitting control signal EM having the maximum pulse width can be applied to the main light-emitting element 200 of the 1-1 sub-pixel PXL1_SP1 which is a single-chip sub-pixel. In the third brightness section LB3, the magnitude of the data voltage applied by the single data line Vdata_S can be adjusted to increase the brightness of the main light-emitting element 200 of the 1-1 sub-pixel PXL1_SP1 which is a single-chip sub-pixel. In the third brightness section LB3, a data voltage higher than the data voltage provided in the first brightness section LB1 can be applied to the main light-emitting element 200 of the 1-1 sub-pixel PXL1_SP1 which is a single-chip sub-pixel at an efficiency lower than the maximum EQE.

[0172] In the third luminance section LB3, the emission control signal EM having the maximum pulse width can be applied to the main light-emitting element 200 of the 2-1 sub-pixel PXL2_SP1, which is a dual-chip sub-pixel, through the main emission control line EM_m. The main emission control line EM_m simultaneously controls the luminance of the main light-emitting element 200 of the 1-1 sub-pixel PXL1_SP1, which is a single-chip sub-pixel. In this case, the data voltage can be provided through the second dual data line Vdata_D2, or the emission control signal EM provided by the auxiliary emission control line EM_r that operates independently of the main emission control line EM_m can be provided to the auxiliary light-emitting element 200 of the 2-1 sub-pixel PXL2_SP1, which is a dual-chip sub-pixel. Preferably, in order to achieve the maximum target luminance in the third luminance section LB3, the emission control signal EM provided by the auxiliary emission control line EM_r can be provided to the auxiliary light-emitting element 200 of the 2-1 sub-pixel PXL2_SP1, which is a dual-chip sub-pixel. In this case, the emission control signal EM can have the maximum pulse width.

[0173] In the third luminance section LB3, although the emission control signal EM having the maximum pulse width is provided to the auxiliary light-emitting element 200 of the 2-1 sub-pixel PXL2_SP1 through the auxiliary emission control line EM_r, when the 2-1 sub-pixel PXL2_SP1 cannot achieve the maximum target luminance, a data voltage higher than the data voltage provided in the first luminance section LB1 can also be applied with an efficiency lower than the maximum EQE. In this case, the decrease in EQE of the data voltage provided to the auxiliary light-emitting element 200 of the 2-1 sub-pixel PXL2_SP1 can be smaller than the decrease in EQE of the data voltage provided to the main light-emitting element 200 of the 1-1 sub-pixel PXL1_SP1. The overall light-emitting efficiency of the 2-1 sub-pixel PXL2_SP1 can be increased.

[0174] In the third luminance section LB3, the average value of the EQE of the main light-emitting element and the EQE of the auxiliary light-emitting element included in the 2-1 sub-pixel PXL2_SP1 can be greater than the EQE of the 1-1 sub-pixel PXL1_SP1.

[0175] According to the embodiment, the light-emitting efficiency of the display device including the 1-1 sub-pixel PXL1_SP1 and the 2-1 sub-pixel PXL2_SP1 can be improved as a whole. The display device can have reduced power consumption and can be driven at low power. In addition, the lifespan can be increased and the light extraction characteristics can be enhanced.

[0176] The display device according to an embodiment of the present application can be applied to mobile devices, videophones, smart watches, watch phones, wearable devices, foldable devices, rollable devices, bendable devices, flexible devices, curved devices, sliding devices, variable devices, electronic notebooks, e-books, portable multimedia players (PMPs), personal digital assistants (PDAs), MP3 players, mobile medical devices, desktop PCs, laptop PCs, netbooks, workstations, navigation systems, in-vehicle display devices, theater display devices, televisions, wallpaper devices, signage devices, gaming devices, laptop computers, monitors, cameras, video cameras, household appliances, etc. Additionally, the display device according to one or more embodiments of the present application can be applied to organic light-emitting lighting devices or inorganic light-emitting lighting devices.

[0177] In the display device according to the present application, both the main light-emitting element and the auxiliary light-emitting element can be utilized to improve the light efficiency. Additionally, as the light efficiency is improved, the display device can have reduced power consumption.

[0178] The effects of the present application are not limited to the above effects, and those skilled in the art will clearly understand other effects not mentioned from the description of the claims.

[0179] Since the content of the specification described in the above problems to be solved, means for solving the problems, and purposes does not specify the essential features of the claims, the scope of the claims is not limited by the content described in the specification.

[0180] Although the embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not necessarily limited to these embodiments, and various modifications can be made without departing from the technical spirit of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but for illustrative purposes, and the scope of the technical spirit of the present invention is not limited by these embodiments. Therefore, it should be understood that the above embodiments are illustrative in all aspects and not restrictive.

Claims

1. A display device, comprising: A first sub-pixel, the first sub-pixel comprising a first light-emitting element and a first pixel driving circuit driving the first light-emitting element; as well as a second sub-pixel, the second sub-pixel comprising a second light-emitting element, a second pixel driving circuit driving the second light-emitting element, a third light-emitting element, and a third pixel driving circuit driving the third light-emitting element, When the target brightness of the first sub-pixel is included in the high brightness portion, the first pixel driving circuit controls the first light-emitting element to emit light in a first control mode. When the target brightness of the second sub-pixel is included in the high brightness portion, the second pixel driving circuit controls the second light emitting element to emit light in a second control mode.

2. The display device according to claim 1, wherein: In the first control mode, the amplitude of the data signal is changed to adjust the brightness of the light emitting element. In the second control mode, the amplitude of the data signal is maintained.

3. The display device according to claim 1, wherein: The first sub-pixel and the second sub-pixel realize the same color.

4. The display device according to claim 2, wherein: When the target brightness of the first sub-pixel is included in the low brightness portion, the first pixel driving circuit controls the first light emitting element to emit light in the first control mode, When the target brightness of the second sub-pixel is included in the low brightness portion, the second pixel driving circuit controls the second light emitting element to emit light in the first control mode.

5. The display device according to claim 4, wherein: When the target brightness of the first sub-pixel is included in the middle brightness portion between the low brightness portion and the high brightness portion, the first pixel driving circuit controls the first light emitting element to emit light in the second control mode and changes the light emission time of the first light emitting element to adjust the brightness of the first light emitting element. When the target brightness of the second subpixel is included in the medium brightness portion, the second pixel driving circuit controls the second light emitting element to emit light in the second control mode and changes the light emission time of the second light emitting element to adjust the brightness of the second light emitting element.

6. The display device according to claim 5, wherein: At least one of the first light emitting element and the second light emitting element has a maximum external quantum efficiency (EQE) in the middle brightness portion.

7. The display device according to claim 6, wherein: In the second control mode, the amplitude of the data signal is maintained to correspond to the maximum external quantum efficiency.

8. The display device according to claim 1, wherein: When the target brightness of the second sub-pixel is included in the high brightness portion, the third pixel driving circuit controls the third light emitting element to emit light.

9. The display device according to claim 8, wherein: The third pixel driving circuit adjusts the brightness of the third light emitting element by changing the amplitude of the data signal.

10. The display device according to claim 8, wherein: The third pixel driving circuit adjusts the brightness of the third light emitting element by changing the light emitting time of the third light emitting element.

11. The display device according to claim 5, wherein: Each of the first pixel driving circuit, the second pixel driving circuit and the third pixel driving circuit comprises: a driving transistor, the driving transistor providing a driving current for driving a light emitting element according to the data signal; and A light emitting transistor applies the driving current to the light emitting element according to a light emitting control signal.

12. The display device according to claim 11, wherein: The data signal comprises a pulse amplitude modulated signal in analog form, The light emission control signal includes a pulse width modulation signal in digital form.

13. The display device according to claim 12, wherein: When the target brightness of the first sub-pixel is the maximum brightness in the low brightness portion, a light emission control signal having a minimum pulse width is applied to the first pixel driving circuit, When the target luminance of the second sub-pixel is the maximum luminance in the low luminance portion, a light emission control signal having a minimum pulse width is applied to the second pixel driving circuit.

14. The display device according to claim 12, wherein: When the target brightness of the first sub-pixel is the minimum brightness of the medium brightness part, a light emission control signal having a minimum pulse width is applied to the first pixel driving circuit, When the target brightness of the second sub-pixel is the minimum brightness of the middle brightness part, the light emission control signal having the minimum pulse width is applied to the second pixel driving circuit.

15. The display device according to claim 12, wherein: When the target brightness of the first sub-pixel is the maximum brightness of the middle brightness part, the light emission control signal having the maximum pulse width is applied to the first pixel driving circuit.

16. The display device according to claim 15, wherein: The light emitting control signal having the maximum pulse width includes a duty ratio of 100%.

17. The display device according to claim 15, wherein: When the target brightness of the first sub-pixel is included in the high brightness portion, a light emission control signal having a maximum pulse width is applied to the first pixel driving circuit.

18. The display device according to claim 12, wherein: When the target brightness of the second sub-pixel is the maximum brightness of the high brightness portion, a light emission control signal having a maximum pulse width is applied to the second pixel driving circuit.

19. The display device according to claim 12, wherein: When the target brightness of the first sub-pixel is included in the medium brightness portion, the duty ratio of the light emission control signal applied to the first pixel driving circuit increases as the target brightness of the first sub-pixel increases, When the target brightness of the second sub-pixel is included in the middle brightness section, a duty ratio of the light emission control signal applied to the second pixel driving circuit increases as the target brightness of the second sub-pixel increases.

20. The display device according to claim 11, wherein: The same light emission control signal is applied to the first pixel driving circuit and the second pixel driving circuit.

21. The display device according to claim 8, wherein: In the high-luminance portion, an average value of external quantum efficiencies of the second light-emitting element and the third light-emitting element included in the second pixel driving circuit is greater than an external quantum efficiency of the first light-emitting element included in the first pixel driving circuit.

22. The display device according to claim 1, wherein: At least one of the first light emitting element, the second light emitting element, and the third light emitting element includes an inorganic light emitting diode (LED).

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