Organic light emitting diode display device

Abstract

An organic light emitting diode display device includes a substrate including first to third sub-pixels, first to third light emitting diodes respectively located in the first to third sub-pixels on the substrate, and a transmittance control layer located on an outer surface of the substrate corresponding to an emission direction of light emitted from the first to third light emitting diodes, the transmittance control layer including a first lens and a second lens covering the first lens, wherein one of the first to third sub-pixels includes a green sub-pixel, wherein the first lens is disposed to correspond to an emission area of the green sub-pixel, and wherein the second lens is disposed to correspond to the first to third sub-pixels.

Description

[0001] Cross-reference to related applications

[0002] This patent application claims priority to Korean Patent Application No. 10-2021-0174043, filed in Korea on December 7, 2021, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to organic light-emitting diode (OLED) display devices, and more particularly, to OLED display devices that improve color perception differences based on viewing angle. Background Technology

[0004] Recently, with the advent of the information-oriented society, people's interest in information displays for processing and displaying large amounts of information, as well as the demand for portable information media, has increased, leading to rapid progress in the display field. Consequently, various thin and light flat panel display devices have been developed and given more attention.

[0005] Among various flat panel display devices, organic light-emitting diode (OLED) display devices are emission-type devices and do not include the backlight unit used in non-emission-type devices (such as liquid crystal display (LCD) devices). As a result, OLED display devices have low weight and thin profile.

[0006] Furthermore, compared to LCD devices, OLED displays offer advantages in viewing angle, contrast ratio, and power consumption. Additionally, OLED displays can be driven with low direct current (DC) voltages and have a fast response time. Moreover, because the internal components of OLED displays are solid-phase, they exhibit high resistance to external shocks and have a wide operating temperature range.

[0007] When white is displayed on an OLED display, the perception of white may change depending on the user's viewing angle. When viewing an OLED display showing white from the side, a greenish tinge may appear on the white.

[0008] Users can identify the aforementioned color perception differences, which can lead to luminous degradation, and users may perceive these color perception differences as a degradation of the display. Summary of the Invention

[0009] Accordingly, this disclosure relates to organic light-emitting diode display devices that substantially avoid one or more of the problems caused by limitations and defects in related technologies.

[0010] The purpose of this disclosure is to provide an organic light-emitting display device that improves the greening effect.

[0011] Another object of this disclosure is to provide an organic light-emitting diode display device in which luminous degradation is prevented from being perceived by the user by minimizing the color perception difference of white display.

[0012] Additional features and advantages of this disclosure will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practice of the disclosure. These and other advantages of the disclosure will be realized and obtained by means of the structures specifically pointed out in the description and with respect to the claims and the accompanying drawings.

[0013] To achieve these and other advantages, and in accordance with the purposes of this disclosure, as embodied and broadly described herein, an organic light-emitting diode (OLED) display device includes: a substrate comprising first to third sub-pixels; first to third light-emitting diodes, respectively located on the first to third sub-pixels on the substrate; and a transmission control layer located on an outer surface of the substrate corresponding to the emission direction of light emitted from the first to third light-emitting diodes, the transmission control layer including a first lens and a second lens covering the first lens, wherein one of the first to third sub-pixels includes a green sub-pixel, wherein the first lens is configured to correspond to an emission region of the green sub-pixel, and wherein the second lens is configured to correspond to the first to third sub-pixels.

[0014] It should be understood that the general description above and the detailed description below are illustrative and intended to provide a further explanation of the claimed disclosure. Attached Figure Description

[0015] The accompanying drawings, which are included to provide a further understanding of this disclosure and are incorporated in and form part of this specification, illustrate embodiments of the disclosure. These drawings, together with the textual description, serve to explain the principles of the disclosure. In the drawings:

[0016] Figure 1 This is a cross-sectional view of a unit pixel comprising four sub-pixels in an organic light-emitting diode display device according to an embodiment of the present disclosure;

[0017] Figure 2 This is an illustration of a light-emitting diode (LED) in an organic light-emitting diode display device according to an embodiment of the present disclosure.

[0018] Figure 3A This is a plan view of an organic light-emitting diode display device according to an embodiment of the present disclosure, showing a unit pixel including four sub-pixels;

[0019] Figure 3B This is a diagram illustrating the optical path in the transmission control layer of an organic light-emitting diode display device according to an embodiment of the present disclosure;

[0020] Figure 4 This is a graph showing the spectrum of light passing through the transmission control layer of an organic light-emitting diode display device according to an embodiment of the present disclosure;

[0021] Figures 5A to 5C The graphs show the spectrum relative to the viewing angles of red, green, and blue light that have passed through the substrate of the organic light-emitting diode display device, according to embodiments of the present disclosure.

[0022] Figures 6A to 6C The spectral graphs, according to embodiments of the present disclosure, are shown relative to the viewing angles of red, green, and blue light passing through the first lens of the organic light-emitting diode display device; and

[0023] Figures 7A to 7C The graphs show the spectrum of red, green and blue light, respectively, relative to the viewing angles of the red, green and blue light that have passed through the second lens of the organic light-emitting diode display device, according to embodiments of the present disclosure. Detailed Implementation

[0024] The advantages, features, and implementation methods of this disclosure will become clear and understandable from the following exemplary embodiments described with reference to the accompanying drawings. However, this disclosure may be embodied in various forms and should not be construed as limited to the exemplary embodiments set forth herein. Rather, these exemplary embodiments are provided to make this disclosure thorough and complete, thereby assisting those skilled in the art in fully understanding its scope. Furthermore, this disclosure is limited only by the scope of the claims.

[0025] The shapes, dimensions, scales, angles, and quantities disclosed in the accompanying drawings for the purpose of depicting embodiments of this disclosure are merely examples. Therefore, this disclosure is not limited to the illustrated details. Similar elements are indicated throughout the drawings by similar reference numerals. In the following description, detailed descriptions of relevant known functions or configurations may be omitted where it is determined that such detailed descriptions would unnecessarily obscure the essential points of this disclosure. Where the terms "comprising," "having," and "including" are used as described in this specification, additional parts may be added unless more restrictive terms, such as "only," are used. Singular forms may contain plural forms unless indicated to the contrary.

[0026] When interpreting an element, it will be interpreted as including a certain range of error or tolerance, even if such range of error or tolerance is not explicitly described.

[0027] When describing positional relationships, one or more other parts may be placed between two parts when describing the positional relationship between two parts as (for example) "on", "above", "below", or "next to", unless more restrictive terms such as "exactly" or "directly" are used.

[0028] It should be understood that although terms such as "first" and "second" may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element, without departing from the scope of the invention.

[0029] Features of the various embodiments of this disclosure may be partially or completely coupled or combined with each other, and may be interoperable with each other in various ways and are technology-driven, as will be fully understood by those skilled in the art. Embodiments of this disclosure may be implemented independently of each other, or may be implemented together in an interdependent relationship.

[0030] In the following, a touch device, a touch display device including the touch device, and a method for driving the touch device according to embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the following description, similar reference numerals will always denote similar elements. Detailed descriptions of known functions or configurations related to this document will be omitted or simplified when it is determined that such detailed descriptions would unnecessarily obscure the spirit of the inventive concept.

[0031] Figure 1 This is a cross-sectional view of a unit pixel comprising four sub-pixels in an organic light-emitting diode display device according to an embodiment of the present disclosure, and Figure 2 This is an illustration of a light-emitting diode (LED) in an organic light-emitting diode display device according to an embodiment of the present disclosure.

[0032] Although the driving thin-film transistor (TFT) DTr and the switching thin-film transistor (not shown) are disposed in each of the white sub-pixels W-SP, red sub-pixels R-SP, green sub-pixels G-SP and blue sub-pixels B-SP on the substrate 101, only the driving TFT DTr in one of the white sub-pixels W-SP, red sub-pixels R-SP, green sub-pixels G-SP and blue sub-pixels B-SP are shown for the sake of illustration and simplification.

[0033] exist Figure 1 and Figure 2In the organic light-emitting diode (OLED) display device 100 according to an embodiment of the present disclosure, a plurality of sub-pixels, including a white sub-pixel W-SP, a red sub-pixel R-SP, a green sub-pixel G-SP, and a blue sub-pixel B-SP, are defined on the substrate 101. Although each of the plurality of sub-pixels W-SP, R-SP, G-SP, and B-SP is defined by the intersection of a data line DL and a gate line (not shown), the device is not limited thereto.

[0034] At least three adjacent sub-pixels R-SP, G-SP, and B-SP can constitute a single unit pixel P for color display. For example, a single unit pixel P may include a red sub-pixel R-SP, a green sub-pixel G-SP, and a blue sub-pixel B-SP that are adjacent to each other, and the red sub-pixel R-SP, the green sub-pixel G-SP, and the blue sub-pixel B-SP can emit red, green, and blue light, respectively.

[0035] A single unit pixel P may further include a white sub-pixel W-SP, and a single unit pixel P including a white sub-pixel W-SP, a red sub-pixel R-SP, a green sub-pixel G-SP, and a blue sub-pixel B-SP may have a rectangular shape.

[0036] Each of the white sub-pixel W-SP, red sub-pixel R-SP, green sub-pixel G-SP, and blue sub-pixel B-SP includes a emission region EA, and the embankment 119 is disposed along the boundary of the emission region EA to form a non-emission region NEA.

[0037] A switching TFT and a driving TFT DTr are disposed in the non-emitting region NEA of each of the white sub-pixel W-SP, the red sub-pixel R-SP, the green sub-pixel G-SP, and the blue sub-pixel B-SP, and a light-emitting diode E comprising a first electrode 111, an organic emitting layer 113, and a second electrode 115 is disposed in the emitting region EA of each of the white sub-pixel W-SP, the red sub-pixel R-SP, the green sub-pixel G-SP, and the blue sub-pixel B-SP.

[0038] The switching TFT and the driving TFT DTr are interconnected, and the driving TFT DTr is connected to the light-emitting diode E.

[0039] A semiconductor layer 103 is disposed in the switching region TrA of each of the white sub-pixel W-SP, red sub-pixel R-SP, green sub-pixel G-SP, and blue sub-pixel B-SP on the substrate 101. The semiconductor layer 103 has an active region 103a made of intrinsic silicon forming a channel, and source regions 103b and drain regions 103c made of doped silicon located on both sides of the active region 103a.

[0040] A gate insulating layer 105 is disposed on a semiconductor layer 103.

[0041] The gate electrode 107 is disposed on the gate insulating layer 105 located above the active region 103a of the semiconductor layer 103, and the gate line (not shown) is disposed on the gate insulating layer 105.

[0042] A first interlayer insulating layer 109a is disposed on the gate electrode 107 and the gate line. The first interlayer insulating layer 109a and the gate insulating layer 105 have first and second semiconductor contact holes 116 that expose the source region and drain region 103b and 103c located on both sides of the active region 103a, respectively.

[0043] A source electrode 110a and a drain electrode 110b, spaced apart from each other, are disposed on a first interlayer insulating layer 109a having first and second semiconductor contact holes 116. The source electrode 110a and the drain electrode 110b are connected to the source region 103b and the drain region 103c, respectively, through the first and second semiconductor contact holes 116.

[0044] The second interlayer insulating layer 109b is disposed on the source electrode 110a and the drain electrode 110b, and on the first interlayer insulating layer 109a exposed between the source electrode 110a and the drain electrode 110b.

[0045] The source electrode 110a and drain electrode 110b, the semiconductor layer 103 including the source region 103b and drain region 103c connected to the source electrode 110a and drain electrode 110b, the gate insulating layer 105 located on the semiconductor layer 103, and the gate electrode 107 constitute the driving TFT DTr.

[0046] Although not shown, the switching TFT can have the same structure as the driving TFT DTr and can be connected to the driving TFT DTr.

[0047] Although the switching TFT and driving TFT DTr have a top gate type in this embodiment, in which the semiconductor layer 103 comprises polycrystalline silicon or oxide semiconductor material, in another embodiment, the switching TFT and driving TFT DTr may have a bottom gate type, in which the semiconductor layer 103 comprises intrinsic amorphous silicon and impurity-doped amorphous silicon.

[0048] When the semiconductor layer 103 includes an oxide semiconductor material, a light-shielding layer may be disposed below the semiconductor layer 103, and a buffer layer may be disposed between the light-shielding layer and the semiconductor layer 103.

[0049] The second interlayer insulating layer 109b has a drain contact hole PH that exposes the drain electrode 110b of the driving TFT DTr, and a first electrode 111 is disposed on the second interlayer insulating layer 109b. The first electrode 111 is connected to the drain electrode 110b of the driving TFT DTr through the drain contact hole PH, and includes a material with a relatively high work function, thereby constituting the anode of the light-emitting diode E.

[0050] A first electrode 111 is disposed in each of the white sub-pixel W-SP, red sub-pixel R-SP, green sub-pixel G-SP, and blue sub-pixel B-SP, and a dam 119 is disposed between adjacent first electrodes 111. The first electrode 111 has a separate structure located in each of the white sub-pixel W-SP, red sub-pixel R-SP, green sub-pixel G-SP, and blue sub-pixel B-SP, wherein the dam 119 serves as the boundary between the white sub-pixel W-SP, red sub-pixel R-SP, green sub-pixel G-SP, and blue sub-pixel B-SP.

[0051] An organic emission layer 113 is disposed on the first electrode 111 and the embankment 119. The organic emission layer 113 has a single layer of emission material or has multiple layers consisting of a hole injection layer, a hole transport layer, an emission material layer, an electron transport layer and an electron injection layer.

[0052] In the OLED display device 100, the organic emitting layer 113 of each of the white sub-pixel W-SP, red sub-pixel R-SP, green sub-pixel G-SP and blue sub-pixel B-SP can emit white light.

[0053] The second electrode 115 is disposed on the organic emission layer 113 and the entire substrate 101.

[0054] The second electrode 115 may include a material with a relatively low work function to form the cathode of the light-emitting diode E.

[0055] In the OLED display device 100, when a voltage is applied to the first electrode 111 and the second electrode 115 according to a selected signal, holes injected from the first electrode 111 and electrons injected from the second electrode 115 are transferred to the organic emission layer 113 to form excitons. When the excitons transition from the excited state to the ground state, light that will be emitted as visible rays is generated.

[0056] The light-emitting diode E includes a first electrode 111, a second electrode 115, and first and second emitting layers 125a and 125b located between the first electrode 111 and the second electrode 115.

[0057] The first electrode 111 is the anode supplying holes. The first electrode 111 may comprise metal oxides such as indium tin oxide (ITO) and indium zinc oxide (IZO), mixtures of metals and oxides such as zinc oxide and aluminum (ZnO:Al), tin oxide and antimony (SnO2:Sb), and conductive polymers such as poly(3-methylthiophene), poly(3,4-ethylene-1,2-dioxothiophene) (PEDT), polypyrrole, and polyaniline. Furthermore, the first electrode 111 may comprise carbon nanotubes (CNTs), graphene, and silver nanowires.

[0058] The second electrode 115 is a cathode that supplies electrons and may comprise a material with a relatively low work function. For example, the second electrode 115 may have a single-layer or multi-layer bilayer structure, wherein the multilayer is composed of a metal alloy of a first metal (e.g., silver (Ag)) and a second metal (e.g., magnesium (Mg)).

[0059] A first emitter layer 125a and a second emitter layer 125b, a first hole transport layer (HTL) 121, and a first electron transport layer (ETL) 123 are disposed between a first electrode 111 and a second electrode 115. The first electron transport layer 123 is disposed below the first electrode 115, and the second emitter layer 125b, the first emitter layer 125a, and the first hole transport layer 121 are sequentially disposed below the first electron transport layer 123.

[0060] An electron injection layer (EIL) may be further disposed between the second electrode 115 and the first electron transport layer 123. Electrons can be easily injected from the second electrode 115 into the first electron transport layer 123 through the electron injection layer.

[0061] The first electron transport layer 123 may have at least two layers and may comprise at least two materials. A hole blocking layer (HBL) may be further disposed between the first electron transport layer 123 and the second emitter layer 125b. Because the hole blocking layer prevents holes injected into the second emitter layer 125b from returning to the first electron transport layer 123, the binding of holes and electrons in the second emitter layer 125b is improved, and the emission efficiency of the second emitter layer 125b is also improved.

[0062] The first electron transport layer 123 and the hole blocking layer can be formed from a single layer. The first electron transport layer 123, the hole blocking layer, and the first electron injection layer can be electron transfer layers.

[0063] The first electron transport layer 123 supplies electrons from the second electrode 115 to the second emitter layer 125b, and the first hole transport layer 121 supplies holes from the first electrode 111 to the first emitter layer 125a.

[0064] As a result, electrons supplied through the first electron transport layer 123 and holes supplied through the first hole transport layer 121 recombine in the first emission layer 125a to generate light.

[0065] The first emitting layer 125a can emit a first colored light. For example, the first emitting layer 125a may include one of a blue emitting layer, a dark blue emitting layer, and a sky blue emitting layer. The first colored light emitted from the first emitting layer 125a may have a wavelength in the range of approximately 440 nm to approximately 480 nm.

[0066] The first emitter layer 125a may include at least one host and a dopant, or may include a mixed host having two or more hosts and at least one dopant.

[0067] Hybrid hosts can include hosts with hole transport properties and hosts with electron transport properties. By controlling the charge balance of the emitter layer through hybrid hosts, the efficiency of the emitter layer is improved.

[0068] Dopants can include fluorescent dopants or phosphorescent dopants.

[0069] The second emission layer 125b is disposed on the first emission layer 125a, and the auxiliary layer 127b is disposed between the first emission layer 125a and the second emission layer 125b.

[0070] The auxiliary layer 127 may include a second hole transport layer (HTL) and a second electron transport layer (ETL), and an electron injection layer (EIL) may be further disposed between the second electron transport layer and the first emission layer 125a. The hole injection layer (HIL) may be further disposed on the second hole transport layer.

[0071] An electron blocking layer (EBL) may be further disposed between the first emitter layer 125a and the second hole transport layer. Because the electron blocking layer prevents electrons injected into the first emitter layer 125a from returning to the first hole transport layer, it improves the binding of holes and electrons in the first emitter layer 125a and increases the emission efficiency of the first emitter layer 125a.

[0072] The second hole transport layer and the electron blocking layer can be formed from a single layer, and the hole blocking layer (HBL) can be further disposed on the second electron transport layer to improve the efficiency of the first emitter layer 125a.

[0073] The second electron transport layer and the hole blocking layer can be formed from a single layer. The second electron transport layer, the hole blocking layer, and the electron injection layer can be electron transfer layers, and the second hole transport layer, the electron blocking layer, and the hole injection layer can be hole transfer layers.

[0074] The second emitting layer 125b can emit a second colored light. For example, the second emitting layer 125b may include one of a green emitting layer and a red emitting layer. The second colored light emitted from the second emitting layer 125b may have a wavelength in the range of approximately 510 nm to approximately 650 nm.

[0075] The second emitter layer 125b may include at least one host and a dopant, or may include a mixed host having two or more hosts and at least one dopant.

[0076] Hybrid hosts can include hosts with hole transport properties and hosts with electron transport properties. By controlling the charge balance of the emitter layer through hybrid hosts, the efficiency of the emitter layer is improved.

[0077] Dopants can include fluorescent dopants or phosphorescent dopants.

[0078] A charge generation layer (CGL) may be further disposed between the second electron transport layer and the second hole transport layer of the auxiliary layer 127. The charge generation layer can control the charge balance between the first emitter layer 125a and the second emitter layer 125b.

[0079] The charge generation layer includes a positive charge generation layer (P-CGL) and a negative charge generation layer (N-CGL). The positive charge generation layer can inject holes into the first emitter layer 125a, and the negative charge generation layer can inject electrons into the second emitter layer 125b.

[0080] Although two emission layers 125a and 125b are disposed between the first electrode 111 and the second electrode 115 of the light-emitting diode E according to an embodiment of the present disclosure, in another embodiment, three emission layers may be disposed between the first electrode 111 and the second electrode 115.

[0081] According to an embodiment of the present disclosure, the light-emitting diode E has a double-stacked structure in which blue light emitted from the first emitting layer 125a is mixed with green and red light emitted from the second emitting layer 125b to emit white light.

[0082] An OLED display device 100 including a light-emitting diode E according to an embodiment of the present disclosure has a bottom emission type, such that colored light emitted from the organic emission layer 113 in each of the white sub-pixel W-SP, red sub-pixel R-SP, green sub-pixel G-SP and blue sub-pixel B-SP passes through a first electrode 111.

[0083] The color conversion pattern is set on the first interlayer insulating layer 109a, thereby corresponding to the emission area EA of each of the white sub-pixel W-SP, red sub-pixel R-SP, green sub-pixel G-SP and blue sub-pixel B-SP.

[0084] The color conversion pattern may include color filter patterns W-CF, R-CF, G-CF, and B-CF set to correspond to the white sub-pixel W-SP, red sub-pixel R-SP, green sub-pixel G-SP, and blue sub-pixel B-SP. The color filter patterns W-CF, R-CF, G-CF, and B-CF convert the color of white light emitted by the organic emission layer 113. The white, red, green, and blue filter patterns W-CF, R-CF, G-CF, and B-CF may be set to correspond to the emission areas EA of the white sub-pixel W-SP, red sub-pixel R-SP, green sub-pixel G-SP, and blue sub-pixel B-SP, respectively.

[0085] The white filter pattern W-CF in the emission region EA of the white sub-pixel W-SP can be omitted, and the white light emitted from the organic emission layer 113 can be transmitted intact.

[0086] As a result, in the OLED display device 100 according to an embodiment of the present disclosure, the white sub-pixel W-SP, the red sub-pixel R-SP, the green sub-pixel G-SP, and the blue sub-pixel B-SP emit white, red, green, and blue light respectively, thereby obtaining high-brightness full color.

[0087] A passivation layer 102 in the shape of a thin film and an encapsulation substrate 104 are disposed on the driving TFT DTr and the light-emitting diode E, such that the OLED display device 100 is encapsulated by the passivation layer 102 and the encapsulation substrate 104.

[0088] The passivation layer 102 prevents moisture from penetrating into the OLED display device 100 and protects the light-emitting diodes E and TFTs of the OLED display device 100 from external influences.

[0089] In an OLED display device 100 according to an embodiment of the present disclosure, a transmission control layer 200 is further disposed on the rear surface of a substrate 101 (where light passes).

[0090] The transmission control layer 200 includes a first lens 210 covering the green sub-pixel G-SP, a second lens covering the red sub-pixel R-SP and the blue sub-pixel B-SP, and a planarization layer covering the second lens 220.

[0091] In the OLED display device 100 according to an embodiment of the present disclosure, a greenish tinge in white display depending on the viewing angle is prevented by a transmission control layer 200.

[0092] As a result, by minimizing the color perception difference in white display, an OLED display device 100 was obtained that prevents users from recognizing luminous degradation.

[0093] A polarizer 106 can be disposed on the transmission control layer 200 to prevent a decrease in contrast due to external light. In the OLED display device 100, since the polarizer 106, which blocks external light incident from the outside, is disposed in the transmission direction of light emitted from the organic emission layer 113 (in the driving mode for image display), the contrast is improved.

[0094] Figure 3A This is a plan view of an organic light-emitting diode display device according to an embodiment of the present disclosure, comprising a unit pixel including four sub-pixels. Figure 3B This is a diagram illustrating the optical path in the transmission control layer of an organic light-emitting diode display device according to an embodiment of the present disclosure, and Figure 4 This is a graph showing the spectrum of light passing through the transmission control layer of an organic light-emitting diode display device according to an embodiment of the present disclosure.

[0095] exist Figure 3A , Figure 3B and Figure 4 In this context, a single unit pixel P includes a white sub-pixel W-SP, a red sub-pixel R-SP, a green sub-pixel G-SP, and a blue sub-pixel B-SP. Each of the white sub-pixel W-SP, red sub-pixel R-SP, green sub-pixel G-SP, and blue sub-pixel B-SP includes a emission region EA, and ( Figure 1 The embankment 119 is set along the boundary of the launch area EA to form the non-launch area NEA.

[0096] White sub-pixels W-SP, red sub-pixels R-SP, green sub-pixels G-SP, and blue sub-pixels B-SP can be set alternately in the horizontal direction, and multiple white sub-pixels W-SP, red sub-pixels R-SP, green sub-pixels G-SP, and blue sub-pixels B-SP can be set in the vertical direction.

[0097] As a result, the white sub-pixel W-SP, red sub-pixel R-SP, green sub-pixel G-SP, and blue sub-pixel B-SP were set to have a strip structure.

[0098] Although the white sub-pixel W-SP, red sub-pixel R-SP, green sub-pixel G-SP, and blue sub-pixel B-SP are shown to have the same width for the purpose of illustrating the embodiments, in another embodiment, the white sub-pixel W-SP, red sub-pixel R-SP, green sub-pixel G-SP, and blue sub-pixel B-SP may have different widths.

[0099] In an OLED display device 100 according to an embodiment of the present disclosure, a transmission control layer 200 is disposed on the light-transmitting outer surface of a substrate 101. A first lens 210 of the transmission control layer 200 is configured to correspond to the emission region EA of the green sub-pixel G-SP among the white sub-pixel W-SP, red sub-pixel R-SP, green sub-pixel G-SP, and blue sub-pixel B-SP. A second lens 220 of the transmission control layer 200 is configured to cover the first lens 210, the green sub-pixel G-SP, and the red sub-pixel R-SP and blue sub-pixel B-SP adjacent to the green sub-pixel G-SP.

[0100] The first lens 210 and the second lens 220 will emit organic light from the organic emission layer 113 of each of the white sub-pixel W-SP, red sub-pixel R-SP, green sub-pixel G-SP, and blue sub-pixel B-SP. Figure 2 The emitted light is refracted outwards to improve light extraction efficiency (outward coupling efficiency). The first lens 210 and the second lens 220 may have an outward (upward) convex shape.

[0101] As a result, the first lens 210 and the second lens 220 can have a semi-elliptical or semi-circular cross section, thus having a rounded surface.

[0102] The diameter s1 of the first lens 210 is greater than the width w1 of the emission area EA of the green sub-pixel G-SP, so that the first lens 210 covers the entire emission area EA, and all the light emitted from the emission area EA of the green sub-pixel G-SP is contained by the first lens 210.

[0103] The first lens 210 has a size at least larger than the emission region EA of the green sub-pixel G-SP, so as to cover the entire emission region EA. The width w1 of the emission region EA can correspond to the maximum width in the emission region EA and the non-emission region NEA.

[0104] The height h1 of the first lens 210 can be equal to or less than the diameter s1 of the first lens 210. For example, the height h1 of the first lens 210 can be approximately 0.3 to approximately 1 times the diameter s1 of the first lens 210.

[0105] When the height h1 of the first lens 210 is less than approximately 0.3 times the diameter s1 of the first lens 210, the angle of the rounded surface is relatively small. As a result, light cannot be focused outward (upward), and the light extraction efficiency cannot be improved. When the height h1 of the first lens 210 is equal to or greater than approximately 0.3 times the diameter s1 of the first lens 210, the angle of the rounded surface is relatively large, enabling light to be focused outward (upward) and improving the light extraction efficiency. When the height h1 of the first lens 210 is greater than approximately 1 times the diameter s1 of the first lens 210, the height h1 becomes relatively large. Therefore, the manufacturing process becomes difficult. When the height h1 of the first lens 210 is equal to or less than approximately 1 times the diameter s1 of the first lens 210, the complexity of the manufacturing process is avoided.

[0106] For example, the most effective results can be obtained when the height h1 and diameter s1 of the first lens 210 have a ratio of approximately 0.5:1.

[0107] In the transmission control layer 200, the refractive index of the first lens 210 can be greater than the refractive index of the substrate 101 (where light emitted from the green sub-pixel G-SP passes). For example, the substrate 101 and the first lens 210 can have a refractive index difference equal to or greater than about 0.1.

[0108] In having ( Figure 2 In the OLED display device 100 with light-emitting diode E, when the substrate 101 is formed of glass having a refractive index of about 1.5, the first lens 210 may have a refractive index of about 1.6 to about 1.8.

[0109] As a result, when the green light G1 emitted from the green sub-pixel G-SP passes through the substrate 101 and enters the first lens 210, the green light G1 propagates from the medium of the substrate 101, which has a relatively low refractive index, to the medium of the first lens 210, which has a relatively high refractive index. According to Snell's law, the green light G1 has a refraction angle greater than the angle of incidence relative to the normal of the interface surface between the substrate 101 and the first lens 210.

[0110] The refractive index of the second lens 220 on the first lens 210 is less than that of the first lens 210. For example, the first lens 210 and the second lens 220 may have a refractive index difference equal to or greater than about 0.1.

[0111] When the first lens 210 has a refractive index of about 1.6 to about 1.8, the second lens 220 may have a refractive index of about 1.4 to about 1.5.

[0112] When the green light G1 passing through the substrate 101 and incident on the first lens 210 is refracted by Snell's law at a refraction angle greater than the angle of incidence, the green light G1 is refracted upward at the interface between the first lens 210 and the second lens 220.

[0113] As a result, the green light G1 passing through the first lens 210 is converged upwards. The path of the green light G1 emitted from the green sub-pixel G-SP is altered by the first lens 210, thus converging upwards.

[0114] The first lens 210 and the second lens 220, which covers the red sub-pixel R-SP and the blue sub-pixel B-SP adjacent to the green sub-pixel G-SP, include a light-absorbing material. The light-absorbing material can absorb portions of light having wavelengths emitted from the white sub-pixel W-SP, the red sub-pixel R-SP, the green sub-pixel G-SP, and the blue sub-pixel B-SP.

[0115] For example, the light-absorbing material in the second lens 220 may have an absorption band of about 480 nm to about 600 nm and an absorption wavelength peak of about 530 nm to about 540 nm, so that the light-absorbing material absorbs light with a wavelength of about 530 nm to about 540 nm from the light incident on the second lens 220.

[0116] Light-absorbing materials may include combinations of at least two of pyrrole-methyl absorber dyes, rhodamine absorber dyes, cyanine absorber dyes, and tetrazaporphyrin absorber dyes. For example, light-absorbing materials may include combinations of cyanine absorber dyes and tetrazaporphyrin absorber dyes.

[0117] Since the second lens 220, which is made of light-absorbing material, is configured to cover the first lens 210, the second lens 220 has a first thickness t1 corresponding to the first lens 210 and a second thickness t2 corresponding to the outer periphery of the first lens 210. The second thickness t2 is greater than the first thickness t1.

[0118] The first thickness t1 can be the minimum thickness of the second lens 220, and the second thickness t2 can be freely designed in height to include the first thickness t1 and cover the first lens 210.

[0119] As a result, the second lens 220 is configured such that the first thickness t1 corresponds to the green sub-pixel G-SP, and the second thickness t2 corresponds to the red sub-pixel R-SP and the blue sub-pixel B-SP.

[0120] When the red light R1 and blue light B1 emitted from the red sub-pixel R-SP and the blue sub-pixel B-SP enter the second lens 220, the light with a wavelength of approximately 530 nm to approximately 540 nm in the red light R1 and blue light B1 is absorbed by the light-absorbing material and does not pass through the second lens 220 having a second thickness t2.

[0121] Because a portion of the green light G1 emitted from the green sub-pixel G-SP is transmitted toward the adjacent red sub-pixel R-SP and blue sub-pixel B-SP, the green light G1 partially mixes with the red light R1 and the blue light B1. At the location where the green light G1 is mixed, the light in the band of approximately 530 nm to approximately 540 nm from the red light R1 and the blue light B1 is absorbed by the second lens 220 having a second thickness t2 instead of passing through it.

[0122] As a result, in the red sub-pixel R-SP, only red light R1 with relatively high purity passes through the second lens 220, and in the blue sub-pixel B-SP, only blue light B1 with relatively high purity passes through the second lens 220.

[0123] At positions where light of different wavelengths is not mixed, each of the red light R1 and the blue light B1 is a clear light with relatively high color purity. In the OLED display device 100 according to an embodiment of the present disclosure, only pure red light R1 is emitted through the second lens 220 in the red sub-pixel R-SP and only pure blue light B1 is emitted through the second lens 220 in the blue sub-pixel B-SP. As a result, the color reproduction of the light transmitted through the red sub-pixel R-SP and the blue sub-pixel B-SP is improved.

[0124] Specifically, since light in the band of approximately 530 nm to approximately 540 nm is not mixed with red light R1 and blue light B1, the greening effect caused by green light G1, which corresponds to the band of approximately 530 nm to approximately 540 nm, is prevented for white displays.

[0125] As a result, color perception differences are minimized even when the user changes their viewing angle, and the user is prevented from perceiving it as luminous degradation.

[0126] Because a portion of the white light W1 emitted from the white sub-pixel W-SP is transmitted toward the adjacent red sub-pixel R-SP and blue sub-pixel B-SP, this portion of the white light W1 emitted from the white sub-pixel W-SP passes through the second lens 220. Since light in the white light W1 with a wavelength range of approximately 530 nm to approximately 540 nm is absorbed while passing through the second lens 220, a greenish tint is further prevented.

[0127] Since the second lens 220 is configured to correspond to the green sub-pixel G-SP, light with a wavelength range of approximately 530 nm to approximately 540 nm in the green light G1 emitted from the green sub-pixel G-SP is also absorbed as it passes through the second lens 220. However, since the second lens 220, which corresponds to the first lens 210, has a first thickness t1, the absorption of light with a wavelength range of approximately 530 nm to approximately 540 nm is minimized.

[0128] Since the second lens 220 is formed to have a first thickness t1 and a second thickness t2, the amount of light absorption changes depending on the region through which light passes. For example, light passing through the second lens 220 corresponding to the first thickness t1 may have a first amount of light absorption, and light passing through the second lens 220 corresponding to the second thickness t2 may have a second amount of light absorption greater than the first amount of light absorption.

[0129] Since red light R1 and blue light B1 pass through the second lens 220 having a second thickness t2, light in the red light R1 and blue light B1 with a wavelength range of approximately 530 nm to approximately 540 nm is absorbed as a second light absorption amount. Since green light G1 passes through the second lens 220 having a first thickness t1, light in the green light G1 with a wavelength range of approximately 530 nm to approximately 540 nm is absorbed as a first light absorption amount, which is less than the second light absorption amount.

[0130] The first light absorption can be insignificant compared to the second light absorption. Specifically, since the green light G1 emitted from the green sub-pixel G-SP is converged upwards due to the first lens 210, the first light absorption caused by the second lens 220 can compensate for the amount of light converged by the first lens 210.

[0131] exist Figure 4 In the diagram, the horizontal axis represents wavelength (nm) and the vertical axis represents emission intensity and transmittance.

[0132] Emission intensity is a relative value with respect to the maximum value of the emission spectrum. For example, the emission intensity of blue may peak at a wavelength of approximately 455 nm, that of green may peak at a wavelength of approximately 535 nm, and that of red may peak at a wavelength of approximately 620 nm.

[0133] The transmittance of light L through the transmission control layer 200 is reduced in region A, and the transmission control layer 200 can affect only the band corresponding to region A.

[0134] Region A corresponds to the wavelength band of approximately 530 nm to approximately 540 nm. (The remaining text appears to be a fragmented list of sub-pixels and their components, possibly related to wavelength ranges and wavelengths.) Figure 2 Of the red light R1 and blue light B1 emitted by the organic emitting layer 113, light with a wavelength range of approximately 530 nm to approximately 540 nm is absorbed by the second lens 220 of the transmission control layer 200 and does not pass through the second lens 220.

[0135] As a result, blue light B1 with high purity is emitted from the blue sub-pixel B-SP and red light R1 with high purity is emitted from the red sub-pixel R-SP.

[0136] At positions where light of different wavelengths is not mixed, red light R1, green light G1, and blue light B1 are clear lights with relatively high color purity. In the OLED display device 100 according to an embodiment of the present disclosure, only pure red light R1 is emitted through the second lens 220 of the transmission control layer 200 in the red sub-pixel R-SP, and only pure blue light B1 is emitted through the second lens 220 of the transmission control layer 200 in the blue sub-pixel B-SP. As a result, the color reproducibility of the light transmitted through the white sub-pixel W-SP, red sub-pixel R-SP, green sub-pixel G-SP, and blue sub-pixel B-SP is improved.

[0137] Specifically, since light of different wavelengths is not mixed into red light R1 and blue light B1, the greenish tint caused by green light G1 is prevented for white displays.

[0138] A planarization layer 230 is disposed on the second lens 220 to compensate for the step difference caused by the first lens 210 and the second lens 220.

[0139] For example, the planarization layer 230 may have a thickness of about 5 μm to about 20 μm to compensate for the step difference, and may include organic materials such as polyimide, benzocyclobutene series resins and acrylates.

[0140] The planarization layer 230 may have a similar refractive index to the second lens 220. When the second lens 220 has a refractive index of about 1.4 to about 1.5, the planarization layer 230 may have a refractive index of about 1.4 to about 1.5.

[0141] As a result, light passing through the second lens 220 and incident on the planarization layer 230 is prevented from being refracted at the interface between the second lens 220 and the planarization layer 230 due to the difference in refractive index, thus preventing a change in the optical path. Furthermore, total internal reflection caused by the difference in refractive index between the two media (i.e., the second lens 220 and the planarization layer 230) is prevented.

[0142] Correspondingly, total internal reflection at the interface between the second lens 220 and the planarization layer 230 can be prevented.

[0143] Figures 5A to 5C , Figures 6A to 6C as well as Figures 7A to 7C The experimental results of the spectrum are plotted relative to the perspectives of red, green, and blue light, where the horizontal axis represents the perspective and the vertical axis represents the emission intensity.

[0144] Figures 5A to 5C The graphs show the spectrum of red, green and blue light relative to the viewing angle of the substrate of the organic light-emitting diode display device, respectively, according to embodiments of the present disclosure. Figures 6A to 6C The graphs show the spectrum of red, green and blue light, respectively, relative to the viewing angles of the first lens of the organic light-emitting diode display device, according to embodiments of the present disclosure. Figures 7A to 7C The graphs show the spectrum of red, green and blue light, respectively, relative to the viewing angles of the red, green and blue light that have passed through the second lens of the organic light-emitting diode display device, according to embodiments of the present disclosure.

[0145] exist Figures 5A to 5C In the process, the emission intensity of red light R1 and blue light B1 that have passed through substrate 101 decreases from the front view to the side view, while the emission intensity of green light G1 that has passed through substrate 101 hardly changes with the viewing angle.

[0146] exist Figures 6A to 6C In the process, after the green light G1 passes through the first lens 210, the emission intensity of the green light G1 is maintained in the frontal view, while the emission intensity of the green light G1 decreases in the side view.

[0147] exist Figures 7A to 7C In the middle, after the green light G1 passes through the second lens 220, the emission intensity of the green light G1 in the side view decreases significantly.

[0148] As a result, since the green light G1 that has passed through the first lens 210 and the second lens 220 has a similar emission intensity to the red light R1 and the blue light B1 in the side view, the greenish tinge that is seen in the white display is prevented.

[0149] Furthermore, it minimizes color perception differences in white displays and prevents users from recognizing OLED display devices with degraded light emission.

[0150] In the OLED display device 100 according to an embodiment of the present disclosure, a transmission control layer 200 is disposed on the light-transmitting outer surface of the substrate 101. A first lens 210 of the transmission control layer 200 is configured to correspond to the emission region EA of the green sub-pixel G-SP among the white sub-pixel W-SP, red sub-pixel R-SP, green sub-pixel G-SP, and blue sub-pixel B-SP, and a second lens 220 of the transmission control layer 200 is configured to cover the first lens 210, the green sub-pixel G-SP, and the red sub-pixel R-SP and blue sub-pixel B-SP adjacent to the green sub-pixel G-SP. As a result, a greenish tinge is prevented from appearing in white displays.

[0151] Furthermore, it minimizes color perception differences in white displays and prevents users from recognizing OLED display devices with degraded light emission.

[0152] Furthermore, color reproduction is improved because red light R1 and blue light B1 with high purity are emitted from the red sub-pixel R-SP and the blue sub-pixel B-SP.

[0153] Although in the OLED display device 100 according to the embodiments of the present disclosure ( Figure 2 The light-emitting diode E includes ( Figure 2 In one embodiment, the light-emitting diode has two emission layers 125a and 125b, but in another embodiment, the light-emitting diode may include three emission layers.

[0154] When a light-emitting diode includes three emission layers, the three emission layers may include a blue emission layer, a red emission layer, and one of a blue, dark blue, and sky blue emission layer.

[0155] Transmission control layer 200 can be applied to structures exhibiting greening, including double-stacked structures. Figure 2 OLED display device 100 with light-emitting diode E.

[0156] Although in an OLED display device 100 according to an embodiment of the present disclosure a single second lens 220 covers the red sub-pixel R-SP, green sub-pixel G-SP and blue sub-pixel B-SP of two adjacent unit pixels P, in another embodiment the second lens may cover the red, green and blue sub-pixels of each unit pixel.

[0157] Although the OLED display device 100 in one embodiment has a bottom emission type, in another embodiment the transmission control layer may be disposed on the outer surface of the substrate or encapsulating substrate corresponding to the emission direction, regardless of this type.

[0158] When the OLED display device 100 has a top-emitting type, the transmission control layer 200 can be disposed on the outer surface of the encapsulation substrate 104, and the refractive index of the first lens 210 of the transmission control layer 200 is greater than the refractive index of the encapsulation substrate 104. Furthermore, when the encapsulation substrate 104 is omitted and the passivation layer 102 is exposed, the transmission control layer 200 is disposed on the outer surface of the passivation layer 102, and the refractive index of the first lens 210 of the transmission control layer 200 is greater than the refractive index of the passivation layer 102.

[0159] Therefore, in the OLED display device 100 according to the embodiments of the present disclosure, color perception differences can be minimized and luminous degradation can be prevented from being detected by the user.

[0160] It will be apparent to those skilled in the art that various modifications and variations can be made to this disclosure without departing from its scope. Therefore, this disclosure is intended to cover any modifications and variations made to this disclosure that fall within the scope of the appended claims.

Claims

1. An organic light-emitting diode (OLED) display device, comprising: The substrate includes the first to third sub-pixels; The first to third light-emitting diodes in the first to third sub-pixels respectively located on the substrate; as well as A transmission control layer is located on the outer surface of the substrate corresponding to the emission direction of light emitted from the first to third light-emitting diodes. The transmission control layer includes a first lens and a second lens covering the first lens. Wherein, one of the first to third sub-pixels includes a green sub-pixel. The first lens is configured to correspond only to the emission region of the green sub-pixel, and The second lens is configured to correspond to the first to third sub-pixels, and the refractive index of the first lens is greater than that of the second lens.

2. The apparatus according to claim 1, wherein, The second lens has an absorption wavelength peak of 530 nm to 540 nm.

3. The apparatus according to claim 1, wherein, The second lens has a first thickness corresponding to the green sub-pixel and a second thickness corresponding to the outer periphery of the first lens. The second thickness is greater than the first thickness.

4. The apparatus according to claim 3, wherein, The first thickness is the minimum thickness of the second lens.

5. The apparatus according to claim 1, wherein, The refractive index of the first lens is 0.1 or more greater than the refractive index of the substrate and the second lens.

6. The apparatus according to claim 5, wherein, The first lens has a refractive index of 1.6 to 1.

8.

7. The apparatus according to claim 6, wherein, The second lens has a refractive index of 1.4 to 1.

5.

8. The apparatus according to claim 7, wherein, The transmission control layer further includes a planarization layer covering the second lens, and The planarization layer has a refractive index of 1.4 to 1.

5.

9. The apparatus according to claim 1, wherein, The first to third sub-pixels include one of the red sub-pixels and the blue sub-pixels.

10. The apparatus according to claim 1, wherein, The first to third light-emitting diodes emit white light, and The red, green, and blue filter patterns are disposed between the transmission control layer and the first to third light-emitting diodes to correspond to the emission areas of the first to third sub-pixels.

11. The apparatus according to claim 1, wherein, The substrate further includes white sub-pixels, and The fourth light-emitting diode is disposed in the white sub-pixel on the substrate.

12. The apparatus according to claim 11, wherein, A white filter pattern is disposed between the transmission control layer and the fourth light-emitting diode to correspond to the emission area of ​​the white sub-pixel.

13. The apparatus according to claim 1, wherein, The second lens is in contact with the outer surface of the substrate.

14. The apparatus according to claim 11, wherein, The white sub-pixel is exposed outside the second lens.

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