Full-color module with ultra-wide color gamut

Abstract

This invention relates to a full-color module based on pixels in a specific form suitable for use in displays. The full-color module is based on RGCB pixels composed of four color light sources: red (R), green (G), cyan (C), and blue (B), including: a red light source with a peak wavelength of 630–655 nm; a green light source with a peak wavelength of 515–555 nm; a cyan light source with a peak wavelength of 490–505 nm; and a blue light source with a peak wavelength of 455–470 nm. In this case, the green light source may include a light source with a peak wavelength of 520–535 nm, or include a light source with a peak wavelength of 515–530 nm and a light source with a peak wavelength of 540–555 nm. The full-color module of this invention can display rich hues within the UWCG color gamut, has excellent luminous efficiency and durability, and, due to the improved integration of the LED array itself, facilitates the achievement of higher resolution.

Description

Technical Field

[0001] The present invention relates to a full-color module based on pixels in a specific form that can be used in a display, and more particularly to a full-color module utilizing an LED array. Background Technology

[0002] Recently, advancements in high-quality thin-film growth and device fabrication technologies have enabled the fabrication of light-emitting devices of various sizes. In particular, micro-LED display devices that directly combine the three primary colors of light—blue (B), green (G), and red (R)—using micro-LEDs smaller than 100 μm are being actively developed to display full-color images without an LCD.

[0003] Traditionally, the manufacturing technology of micro-LED-based displays is broadly divided into two types based on how RGB pixels are constructed. The first method combines individual blue, green, and red micro-LEDs to form RGB pixels, while the second method combines blue micro-LEDs with green and red phosphors surrounding them. Similar to the latter, RGB pixels can be fabricated by surrounding UV-emitting micro-LEDs with blue, green, and red phosphors.

[0004] In the former case, the production capacity and yield are low due to the difficulty of transferring and assembling individual red, green, and blue micro-LEDs onto the display substrate to form RGB pixels. Furthermore, in the case of green micro-LEDs, the luminous efficiency is very low compared to blue and red micro-LEDs, thus reducing the overall efficiency of the RGB pixels. In the case of red micro-LEDs, because they are made from nitride semiconductors instead of non-nitride semiconductors, they exhibit thermal instability compared to blue and green micro-LEDs; their emission wavelength is easily affected by ambient temperature, making it difficult to ensure color stability.

[0005] In the latter case, the single-chip process is basically based on a blue micro-LED array, and RGB pixels are formed by surrounding specific blue micro-LEDs with green and red phosphors, thus offering better productivity than the former case. However, the display efficiency is lower than the former case because it is difficult to make the performance of the micro-LEDs constituting the array uniform, and the conversion efficiency of the phosphors varies and is not high.

[0006] Therefore, while improving the performance of micro-LEDs in order to reduce the performance and manufacturing cost of micro-LED displays, it is necessary to develop full-color modules based on new pixels capable of displaying colors above the WCG (Wide Color Gamut) of BT. 2020 and their manufacturing methods.

[0007] Existing technical documents

[0008] Non-patent literature

[0009] Non-Patent Literature 1: Enhancement of output power of GaN light-emitting diode with p-type ZnO hole injection layer, BJ Kim et al., Applied Physics Communications 94 (2009), pp. 103506;

[0010] Non-Patent Literature 2: The effect of p-ZnO insertion layer on the external quantum efficiency of GaInN light-emitting diode, Guan-BoLin et al., Applied Physics Letters 8 (2015), pp. 092-102. Summary of the Invention

[0011] Technical issues

[0012] The object of this invention, which addresses the aforementioned problems of the prior art, is to provide a full-color module based on novel pixels, capable of displaying rich hues within the UWCG (Ultra Wide Color Gamut) color gamut, exceeding BT 2020 WCG level. Another object of this invention is to implement the pixels of such a full-color module as an LED array, where each LED constituting a pixel possesses excellent luminous efficiency and excellent durability due to low leakage current. Furthermore, the improved integration of the LED array itself contributes to a higher resolution full-color module.

[0013] Technical solution

[0014] To address the aforementioned issues, this invention was completed after dedicated research.

[0015] This invention provides a full-color module based on RGCB pixels, which is composed of four color light sources: red (R), green (G), cyan (C), and blue (B). The full-color module based on RGCB pixels may include: a red light source with a peak wavelength of 630~655nm; a green light source with a peak wavelength of 515~555nm; a cyan light source with a peak wavelength of 490~505nm; and a blue light source with a peak wavelength of 455~470nm.

[0016] Alternatively, the green light source may include a first green light source with a peak wavelength of 520~535nm.

[0017] The green light source may include a second green light source with a peak wavelength of 515-530nm and a third green light source with a peak wavelength of 540-555nm.

[0018] The blue light source could be a blue LED made of GaN, or a blue hybrid LED with a p-type layer made of ZnO and GaN.

[0019] It could be that the cyan light source is a cyan LED made of GaN, or a cyan hybrid LED with a p-type layer made of ZnO and GaN.

[0020] Alternatively, the first green light source can be constructed by combining a first green phosphor with a blue LED, wherein the blue LED is an LED made of GaN or a hybrid LED with a p-type layer made of ZnO and GaN, and the first green phosphor converts blue light into green light with a corresponding peak wavelength.

[0021] Alternatively, the second green light source and the third green light source can be constructed by combining a second green phosphor and a third green phosphor with a blue LED. The blue LED is an LED made of GaN or a hybrid LED with a p-type layer made of ZnO and GaN. The first green phosphor and the second green phosphor convert blue light into green light with their respective peak wavelengths.

[0022] Alternatively, the red light source can be constructed by combining a red phosphor with a cyan LED, wherein the cyan LED is an LED made of GaN or a hybrid LED with a p-type layer made of ZnO and GaN, and the red phosphor converts cyan light into red light with a corresponding peak wavelength.

[0023] Alternatively, the red light source can be constructed by combining a red phosphor with a blue LED, the blue LED being an LED made of GaN, or a hybrid LED with a p-type layer made of ZnO and GaN, and the red phosphor converting blue light into red light with a corresponding peak wavelength.

[0024] Alternatively, the color light source may be composed of an LED array, and the LED array layer may be a structure that is stacked on the TFT layer and connected to electrodes.

[0025] Alternatively, the unit pixel of the LED array may include two blue LEDs and two cyan LEDs, with one of the two blue LEDs combined with a first green phosphor for converting blue light into green light with a peak wavelength of 520~535nm, and one of the two cyan LEDs combined with a red phosphor for converting cyan light into red light with a corresponding peak wavelength.

[0026] Alternatively, each pixel of the LED array may include three blue LEDs and two cyan LEDs. Two of the three blue LEDs are respectively combined with a second green phosphor for converting blue light into green light with a peak wavelength of 515~530nm and a third green phosphor for converting blue light into green light with a peak wavelength of 540~555nm. One of the two cyan LEDs is combined with a red phosphor for converting cyan light into red light with a corresponding peak wavelength.

[0027] Alternatively, the unit pixel of the LED array may include three blue LEDs and two cyan LEDs. Two of the three blue LEDs are respectively combined with a first green phosphor for converting blue light into green light with a peak wavelength of 520~535nm and a red phosphor for converting blue light into red light with the corresponding peak wavelength. One of the two cyan LEDs is combined with another red phosphor for converting cyan light into red light with the corresponding peak wavelength.

[0028] Alternatively, the full-color module based on RGCB pixels can be a structure consisting of multiple layers composed of LED array layers and TFT layers stacked on top of each other, and the RGCB pixel pattern is a pattern formed by orthographically projecting and combining the pixel patterns of each of the multiple stacked LED array layers.

[0029] The plurality of LED array layers may include: a blue LED array layer with LEDs arranged according to a BG pixel pattern or a BGR pixel pattern; and a cyan LED array layer with LEDs arranged according to an RC pixel pattern.

[0030] Alternatively, the full-color module based on RGCB pixels may further include: an optical film disposed on the light-emitting side of the LED array layer, wherein visible light is opaque in the optical film except for the pixel pattern corresponding to the pixels of the relevant LED array layer.

[0031] It is possible that a phosphor for converting blue light into green light, or a phosphor for converting blue light or cyan light into red light, is formed in a portion of the pixel pattern of the optical film.

[0032] The effects of the invention

[0033] The present invention utilizes a full-color module based on RGCB pixels, employing four color light sources—red (R), green (G), cyan (C), and blue (B)—within a specific wavelength range to construct a display panel that can display a richer color gamut than the UWCG color gamut, which is wider than that of BT. 2020 WCG. Furthermore, such a full-color module utilizes one or more LED arrays fabricated monolithically, enabling the production of UWCG-grade LED display panels of various sizes at a high speed. In this case, the application of hybrid LEDs improves luminous efficiency and reduces heat generation due to leakage current, thereby enhancing durability. Additionally, vertically stacking multiple LED arrays increases integration, thus improving not only brightness and color perception but also resolution. Attached Figure Description

[0034] Figure 1 It is a color chromatic diagram showing the wavelength range of the light source required to realize the UWCG color gamut of an embodiment of the present invention.

[0035] Figure 2 This is a schematic diagram illustrating the process of fabricating an LED display panel using an LED array according to an embodiment of the present invention.

[0036] Figure 3 This is a vertical cross-sectional structural diagram of the epitaxial layer of the hybrid LED according to an embodiment of the present invention.

[0037] Figure 4 It is used for presentation according to embodiments of the present invention. Figure 1 A planar pattern of each RGCB pixel in the UWCG-1 and UWCG-2 color gamuts.

[0038] Figure 5(a), Figure 5(b) and Figure 6 Presented in accordance with embodiments of the present invention Figure 1 A planar schematic diagram of the structure of multiple LEDs and the emitted light patterns in each layer, for each of the UWCG-1 and UWCG-2 color gamuts.

[0039] Figure label:

[0040] 10: LED array; 11: Hybrid micro LEDs; 15: Passivation layer; 25-1: p-electrode; 25-2: n-electrode; 35: Sapphire transparent substrate; 40: n-type layer; 50: Active layer; 60-1: p-type nitride semiconductor layer; 60-2: p-type oxide semiconductor layer; 100, 100A, 100A', 100B, 100B': Full-color module; 111-1: RGCB pixel; 111-2: RGGCB pixel; 105, 205: TFT layer; 110 C array, 210: B array, 115, 215: passivation layer, 125-1, 225-1: p electrode, 125-2, 225-2: n electrode, 135, 235: transparent substrate, 145, 145a: optical film for C array pixels, 245, 245a: optical film for B array pixels, 227: n electrode metal exclusion region, 305, 405: TFT-based substrate, 310: C array, 410: B array, 315, 415: passivation layer, 325-1, 425-1: p electrode, 325-2, 425-2: n electrode, 335, 435: transparent substrate, 345, 345a: optical film for C array pixels, 445, 445a: optical film for B array pixels, 427: n electrode metal exclusion region. Detailed Implementation

[0041] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. In describing the present invention, detailed descriptions of relevant prior art may be omitted where such descriptions would obscure the essence of the invention. Parts unrelated to the description of the present invention are omitted from the drawings; similar reference numerals are used throughout the specification to describe similar parts. In the entirety of the specification, when a part is referred to as "comprising" a certain element, unless otherwise stated, it means that other elements may also be included, rather than excluding other elements.

[0042] First, the full-color module of the present invention is based on RGCB pixels composed of four color light sources: red (R), green (G), cyan (C), and blue (B). By selecting these four color light sources as specific wavelength ranges, it presents colors in the UWCG color gamut that exceed the previous WCG color gamut.

[0043] Figure 1 This is a color chromatic diagram showing the light source required to present the UWCG color gamut and the colors of that region according to a preferred embodiment of the present invention, and, as an embodiment of the UWCG color gamut, the UWCG-1 color gamut and the UWCG-2 color gamut are illustrated.

[0044] Reference Figure 1 Regarding the wavelength ranges of the four color light sources used to achieve the UWCG color gamut—red (R), green (G), cyan (C), and blue (B)—the range includes: a red light source with a peak wavelength of 630–655 nm; a green light source with a peak wavelength of 515–555 nm; a cyan light source with a peak wavelength of 490–505 nm; and a blue light source with a peak wavelength of 455–470 nm. More preferably, in this case, the peak wavelength of the red light source is 645–655 nm, the peak wavelength of the cyan light source is 495–500 nm, and the peak wavelength of the blue light source is 460–465 nm.

[0045] Here, the wavelength band of the green light source can be configured differently depending on the UWCG-1 and UWCG-2 color gamuts. Specifically, the UWCG-1 color gamut comprises a first green light source, and the peak wavelength of the first green light source is 520~535nm, more preferably 530~535nm. In this case, based on the number of light sources, the pixel unit required to achieve full color is an RGCB pixel. In contrast, the UWCG-2 color gamut comprises a second green light source and a third green light source, the peak wavelength of the second green light source is 515~530nm, more preferably 520~525nm, and the peak wavelength of the third green light source is 540~555nm, more preferably 545~550nm. In this case, based on the number of light sources, the pixel unit required to achieve full color is an RGGCB pixel. On the other hand, in this invention, when referring to pixels that are the pixel units required to achieve full color, they are generally referred to as RGCB pixels in both the UWCG-1 and UWCG-2 color gamuts, based on the type of color. Furthermore, depending on the situation, they are referred to as RGCB pixels or RGGCB pixels, as described above, based on the number of light sources.

[0046] According to a preferred embodiment of the present invention, the color light source is composed of an LED array 10. Figure 2 This diagram illustrates the process of sequentially fabricating a full-color module 100 and an LED display panel 1000 using such an LED array 10. It is assumed that the LED array 10 is coupled to the TFT as a driving switching element, as... Figure 2As shown, based on the LED array 10, a full-color module 100 and display panels 1000 of various sizes utilizing it can be fabricated. According to an embodiment, as the light-emitting elements constituting the LED array 10, the LED 11 employs both blue LEDs and cyan LEDs. To fabricate a UWCG-level full-color module 100, as described later, it is preferably configured as a "hybrid LED." Furthermore, from a resolution perspective, the LED 11 should be formed as small as possible, preferably 1 to 50 μm, and more preferably 5 to 30 μm, as a "micro LED." To briefly describe the process of creating a full-color module 100 based on RGCB pixels 111 capable of displaying colors in the UWCG color gamut by using the light-emitting elements of the LED array 10 as such "hybrid micro-LEDs" 11, firstly, a hybrid micro-LED array 10 with a size of 1 to 50 μm, preferably 5 to 30 μm, emitting cyan light with a peak wavelength of 490 to 505 nm and blue light with a peak wavelength of 455 to 470 nm can be created using a conventional semiconductor monolithic integration process using an epitaxial wafer with a light-emitting element structure composed of a ZnO (zinc oxide)-based oxide semiconductor and a GaN (gallium nitride)-based nitride semiconductor.

[0047] On the other hand, when both blue and cyan LEDs are used as light-emitting elements constituting the LED array 10, the blue light source is composed of the blue LED itself, the green light source is composed of the blue LED and a green phosphor, the cyan light source is composed of the cyan LED itself, and the red light source is composed of the cyan LED and a red phosphor. In this case, the blue LED and the cyan LED emit blue light and cyan light, respectively, at the peak wavelengths required to achieve full color, the green phosphor converts the blue light into green light at the peak wavelength required to achieve full color, and the red phosphor converts the cyan light into red light at the peak wavelength required to achieve full color.

[0048] In this case, when realizing full-color pixels based on the aforementioned blue LEDs, cyan LEDs, green phosphors, and red phosphors to achieve UWCG-level full color, the technical difficulties that occur in manufacturing full-color pixels composed of individual blue, cyan, green, and red LEDs can be overcome. Furthermore, the problem of the lack of a cyan phosphor capable of converting blue light into cyan light can be overcome, which is one of the technical limitations of achieving color by combining blue LEDs and phosphors of a specific color in the conventional way.

[0049] While the blue and cyan LEDs can be made of GaN-based nitride semiconductors, there is a tendency for a significant decrease in device performance when LEDs are fabricated in a smaller chip size based on such conventional GaN as the aforementioned “micro-LEDs.” To compensate for this, it is preferable, in particular, to be made of “hybrid LEDs.” Hybrid LEDs are structures in which the p-type layer is composed of GaN-based nitride semiconductors and ZnO-based oxide semiconductors. They are believed to improve internal luminous efficiency (IQE) and reduce heat generation caused by surface leakage current, thereby improving durability (Enhanced output power of GaN LEDs with p-type ZnO hole injection layers, authors: BJ Kim et al., Applied Physics Letters 94 (2009), p. 103506 / / Influence of p-ZnO insertion layers on external quantum efficiency of GaInN LEDs, authors: Guan-Bo Lin et al., Applied Physics Letters 8 (2015), p. 092102). Using such hybrid LEDs as micro-LEDs to form pixels can solve problems related to the efficiency of conventional light-emitting elements, and the matters described in the above-cited documents can be incorporated into this invention.

[0050] Figure 3 A vertical cross-sectional view of the epitaxial layer of the hybrid micro-LED 11 according to a preferred embodiment of the present invention is shown. As described above, Figure 3 The hybrid micro LED11 can be fabricated with a chip size of 1~50μm, preferably 5~30μm, and emit blue light with a peak wavelength of 455~470nm or cyan light with a peak wavelength of 490~505nm. It is manufactured by conventional semiconductor processes as an epitaxial wafer of a light-emitting element structure composed of GaN-based nitride semiconductors and ZnO-based oxide semiconductors.

[0051] Specifically, the hybrid micro-LED 11 is configured to include: an n-type nitride semiconductor layer 40 epitaxially stacked on the substrate 35 to provide electrons; an active layer 50 epitaxially stacked on the n-type nitride semiconductor layer 40 to generate light; a p-type nitride semiconductor layer 60-1 epitaxially stacked on the active layer 50 to provide holes; and a p-type oxide semiconductor layer 60-2 epitaxially stacked on the p-type nitride semiconductor layer 60-1. In this case, the p-type oxide semiconductor layer 60-2 epitaxially stacked on the p-type nitride semiconductor layer 60-1 can be formed as a thin film structure with an As-doped p-type ZnO layer deposited. The p-type ZnO layer 60-2 serves to provide the active layer 50 with holes that are relatively scarce compared to electrons, thereby improving light output.

[0052] The p-type layer of the hybrid micro-LED 11 is characterized by being composed of a p-type heterosemiconductor layer, wherein the p-type ZnO layer 60-2 is deposited on top of the p-type nitride semiconductor layer 60-1 by an epitaxial single-crystal formation method. As described in the cited literature above, the luminous efficiency of the hybrid micro-LED 11 is higher than that of a conventional micro-LED composed only of a nitride semiconductor layer. Therefore, using such a hybrid micro-LED 11 as a light source can lead to the development of high-efficiency display panels.

[0053] The hybrid micro LED11 chip process is accomplished by forming p-electrodes 25-1 and n-electrodes 25-2 made of metal with good reflectivity, and forming an insulating passivation layer 15.

[0054] Next, we will discuss the full-color module 100 capable of presenting the UWCG color gamut according to a preferred embodiment of the present invention, and in particular the RGCB pixels of such a full-color module 100. Figure 2 The production method of (111) will be explained in more detail according to the type. In this case, as mentioned above, when referring to the pixel unit required to achieve full color, it is generally referred to as RGCB pixel in both UWCG-1 and UWCG-2 color gamuts based on the type of color, and further distinguished as RGCB pixel or RGGCB pixel based on the number of light sources, depending on the situation.

[0055] Figure 4 It is a planar pattern diagram for reproducing different types of RGCB pixels 111 (111-1, 111-2) in each of the UWCG color gamut according to an embodiment of the present invention. Figure 4 (a) shows the presentation Figure 1 The UWCG-1 color gamut full-color module 100 consists of RGCB pixels 111-1 composed of four color light sources. Figure 4 (b) shows the presentation Figure 1 The UWCG-2 color gamut full-color module 100 consists of RGCB pixels 111-2 composed of five color light sources. As described above, when the LED array 10 uses both blue LEDs and cyan LEDs, and the blue and cyan light sources are composed of LEDs themselves, while the red and green light sources are composed of LEDs and phosphors, the configuration of each of the RGCB pixels 111 (111-1, 111-2) in the full-color module 100 for the UWCG-1 and UWCG-2 color gamuts is more specifically shown below.

[0056] exist Figure 4In the case of RGCB pixel 111-1 (a), two blue LEDs with a peak wavelength of 455~470nm and two cyan LEDs with a peak wavelength of 490~505nm are arranged in a planar quadrilateral shape to form a unit LED array 10. One of the two blue LEDs is combined with a first green phosphor to convert blue light into green light with a peak wavelength of 520~535nm, and one of the two cyan LEDs is combined with a red phosphor to convert cyan light into red light with a corresponding peak wavelength. Thus, RGCB pixel 111-1 composed of four light sources R, G1, C and B is realized.

[0057] exist Figure 4 In the case of RGGCB pixel 111-2 (b), three blue LEDs with peak wavelengths of 455~470nm and two cyan LEDs with peak wavelengths of 490~505nm are arranged in a planar pentagonal shape to form a unit LED array 10. Two of the three blue LEDs are combined with a second green phosphor for converting green light with a peak wavelength of 515~530nm and a third green phosphor for converting green light with a peak wavelength of 540~555nm, respectively. One of the two cyan LEDs is combined with a red phosphor for converting cyan light into red light with the corresponding peak wavelength. Thus, RGGCB pixel 111-2 composed of five light sources: R, G2, G3, C, and B is realized.

[0058] In the actual fabrication of the full-color module 100, as described above, the LED array 10 layer of the full-color module 100 is used as a driving switching element, and is preferably configured to be stacked on the TFT layer and connected to electrodes. Furthermore, the full-color module 100 may optionally include an optical film disposed on the light-emitting side of the LED array layer. This optical film essentially suppresses the transmission of visible light except for the pixel pattern corresponding to the pixels of the relevant LED array layer. Therefore, although it is assumed that the pixel pattern of the optical film transmits visible light, a phosphor for converting the blue or cyan light of the LED into green or red light can be selectively formed in a portion of it to also perform a color filtering function. On the other hand, although all relevant LEDs can be disposed on the same layer in the LED array 10 layer, as shown in Figures 5(a), 5(b), and below... Figure 6 As shown in the embodiments, from the viewpoint of manufacturing processes for mass production of full-color modules, technical difficulties caused by integration, and manufacturing costs, it is preferable to have LED elements arranged in different layers according to their type, in a stacked structure. In this case, it is preferable that the TFT layer and the optical film are also arranged separately in pairs with each of the 10 LED array layers.

[0059] Figure 5(a), Figure 5(b) and Figure 6 The illustrations are presented in accordance with embodiments of the present invention. Figure 1 The diagram shows a cross-sectional view of a full-color module with multiple LED array layers stacked vertically to accommodate the UWCG-1 and UWCG-2 color gamuts, and a planar schematic of the emitted light pattern in each layer. (See Figures 5(a), 5(b), and...) Figure 6 In this context, the number of LED array layers in each full-color module can be determined by the number of LED types used, as shown in Figures 5(a), 5(b), and 5(c). Figure 6 In the embodiments described, assuming the use of both blue and cyan LEDs, the total number of LED array layers is exemplified as two. Specifically, a blue LED array layer (hereinafter referred to as "B array") is configured on the upper layer, with blue LEDs arranged according to the BG pixel or BGG pixel pattern (hereinafter collectively referred to as BG pixels) constituting the RGCB pixels 111 (111-1, 111-2) of the present invention. A cyan LED array layer (hereinafter referred to as "C array") is configured on the lower layer, with cyan LEDs arranged according to the RC pixel pattern constituting the RGCB pixels 111 (111-1, 111-2) of the present invention. In the following description, BG pixels are referred to as B array pixels, and RC pixels are referred to as C array pixels. Thus, the final RGCB pixel pattern of the full-color module corresponds to a pattern formed by orthographically projecting and combining the pixel patterns of each of the multiple LED array layers stacked as a row. In this case, the vertical arrangement of the B array and C array can be reversed. Furthermore, the TFT layer and optical film can also be separately provided in pairs with each LED array layer.

[0060] Referring to Figures 5(a) and 5(b), in order to fabricate a full-color module 100A, 100A' capable of displaying the UWCG-1 color gamut based on RGCB pixel 111-1 according to an embodiment of the present invention, in the case of the lower C array 110, the C array pixel is fabricated using a monolithic process with a basic form consisting of two cyan mixed micro-LEDs with peak wavelengths of 490~505nm, and in the case of the B array 210, the B array pixel is fabricated using a monolithic process with a basic form consisting of two blue mixed micro-LEDs with peak wavelengths of 455~470nm. In this case, the C array pixels and B array pixels are similar in size, and when each of them is stacked as two layers (upper and lower), the light-emitting surfaces of the mixed micro-LEDs are arranged in a way that does not overlap each other in the vertical direction, so that the final RGCB pixel 111-1 of the full-color module 100A, 100A' becomes a pattern that is orthographically projected and combined from the pixel patterns of each of the B array and C array.

[0061] In the hybrid micro-LED 11 constituting the C array 110 and the B array 210, for the purpose of conventional flip-chip bonding, p-electrodes 125-1 and 225-1 are deposited on the mesa surface, and n-electrodes 125-2 and 225-2 are deposited on the surface of the n-type nitride semiconductor exposed by etching. In this case, in order to prevent the n-electrode metal of the upper B array pixel from interfering with the light emitted by the lower C array pixel when the two layers are stacked, the n-electrode metal 225-2 is preferably not deposited in region 227, which is of a predetermined size and has a shape similar to that of the hybrid micro-LED 11 of the C array pixel, in a region coinciding with the central axis of the micro-LED 11 of the C array pixel.

[0062] In the hybrid micro LED 11, passivation layers 115 and 215 are deposited to insulate the surface except for the partial surface of the electrodes to be bonded using flip chips.

[0063] To electrically regulate each of the hybrid micro-LEDs 11 constituting the C array 110 and the B array 210, electrodes are connected to conventional TFT-base plates 105 and 205 using flip-chip bonding technology. In this case, the TFT-base plate 205 connected to the upper B array 210 is made of a transparent material to allow light emitted from the lower C array pixels to pass through smoothly.

[0064] In the full-color modules 100A and 100A', optical films 145, 245, 145a, and 245a are stacked on transparent substrates 135 and 235. These optical films 145, 245, 145a, and 245a function to allow only light traveling in the vertical direction to pass through, based on the light emitted by the hybrid micro-LEDs 11. In this case, the completed optical films 145, 245, 145a, and 245a can be arranged and stacked using a lamination process, or they can be directly fabricated and stacked on the surface of the sapphire substrates 135 and 235 using a microfabrication process. The lower optical films 145 and 145a are used for pixelation as C-array pixels, and the upper optical films 245 and 245a are used for pixelation as B-array pixels. In this case, each optical film has a pixel pattern corresponding to the pixels of the "corresponding LED array layer". For example, the LED array layer associated with the formation of the pixel patterns of the lower optical films 145 and 145a has only a C array located below it, and the pixels of the lower optical films 145 and 145a have two patterns identical to the C array pixels. However, the LED array layer associated with the formation of the pixel patterns of the upper optical films 245 and 245a has two B arrays and two C arrays displaced below it. Therefore, for the pixels of the upper optical films 245 and 245a, there are a total of four C array pixels projected orthogonally below the B array pixels. It is assumed that the pixels of the upper and lower optical films are formed with similar size and shape in the region that coincides with the central axis of the hybrid micro-LED 11 of the B array and C array pixels. In the optical films, the pixels are formed to be transparent, or formed as red phosphors or green phosphors, and otherwise allocated as visible light opaque regions.

[0065] Specifically, in the case of the lower optical film 145 of the panchromatic module 100A corresponding to FIG. 5(a), two pixels are formed. One pixel is formed to be transparent so that cyan light with a peak wavelength of 490-505nm emitted from the C array pixels can pass through without absorption. The other pixel is formed as a red phosphor capable of converting cyan light with a peak wavelength of 490-505nm into red light with a peak wavelength of 630-655nm. In contrast, in the case of the lower optical film 145a of the panchromatic module 100A' corresponding to FIG. 5(b), two pixels are also formed, both of which are formed to be transparent so that cyan light with a peak wavelength of 490-505nm emitted from the C array pixels can pass through directly without absorption.

[0066] On the other hand, the shape of the upper optical films 245 and 245a is determined according to the shape of the lower optical films 145 and 145a. That is, if the lower optical film is in the shape of 145, the upper optical film is determined to be in the shape of 245; if the lower optical film is in the shape of 145a, the upper optical film is determined to be in the shape of 245a.

[0067] Specifically, in the case of the upper optical film 245 of the panchromatic module 100A corresponding to FIG5(a), a total of four pixels are formed, three of which are formed to be transparent so that cyan light with a peak wavelength of 490~505nm transmitted from the lower C array pixels, red light with a peak wavelength of 630~655nm converted by the red phosphor and transmitted from the lower C array pixels, and blue light with a peak wavelength of 455~470nm emitted from the B array pixels can pass through without absorption, and the remaining pixel is formed to be a first green phosphor that can convert blue light with a peak wavelength of 455~470nm into green light with a peak wavelength of 520~535nm. In contrast, in the case of the upper optical film 245a corresponding to the panchromatic module 100A' in FIG5(b), four pixels are similarly formed, two of which are formed to be transparent so that the cyan light with a peak wavelength of 490~505nm transmitted from the lower C array pixels and the blue light with a peak wavelength of 455~470nm emitted from the upper B array pixels can pass through without absorption. Another pixel is formed to be a red phosphor that converts the cyan light with a peak wavelength of 490~505nm transmitted from the lower C array pixels into red light with a peak wavelength of 630~655nm. The remaining pixel is formed to be a first green phosphor that converts the blue light with a peak wavelength of 455~470nm emitted from the upper B array pixels into green light with a peak wavelength of 520~535nm.

[0068] Reference Figure 6 To fabricate a full-color module 100B, 100B' based on RGGCB pixels 111-2 capable of displaying the UWCG-2 color gamut according to another embodiment of the present invention, in the case of the lower C array 310, a C array pixel is fabricated using a monolithic process with a basic form consisting of two cyan mixed micro-LEDs with peak wavelengths of 490-505nm; in the case of the B array 410, a B array pixel is fabricated using a monolithic process with a basic form consisting of three blue mixed micro-LEDs with peak wavelengths of 455-470nm. In this case, the C array pixels and B array pixels are similar in size, and when each of them is stacked as two layers (upper and lower), the light-emitting surfaces of the mixed micro-LEDs are arranged in a way that they do not overlap in the vertical direction, so that the final RGGCB pixels 111-2 of the full-color modules 100B, 100B' become a pattern that is orthographically projected and combined from the pixel patterns of each of the B and C arrays.

[0069] Another invention, Figure 6 The p-electrodes 325-1, 425-1, n-electrodes 325-2, 425-2, n-electrode metal exclusion region 427, passivation layers 315, 415, and TFT-base plate 405 in the full-color modules 100B and 100B' of the embodiments are the same as those described above in Figures 5(a) and 5(b). Furthermore, regarding... Figure 6 The optical films 345, 445, 345a, 445a and substrates 335, 435 in the full-color modules 100B, 100B' of the embodiments are also basically the same. That is, they are basically the same in that the lower optical films 345, 345a are optical films for pixelation as C-array pixels and the upper optical films 445, 445a are optical films for pixelation as B-array pixels. Furthermore, in Figure 6 The pixelation method of the two pixels in the lower optical films 345, 345a and the morphology of the upper optical films 445, 445a are also the same as those in the embodiments of FIG5(a) and FIG5(b), but, in terms of Figure 6 Regarding the detailed pixelation of the five pixels of the upper optical films 445 and 445a, the details vary slightly as the number of pixels changes, as shown below.

[0070] In corresponding Figure 6 In the case of the upper optical film 445 of the panchromatic module 100B in (a), a total of five pixels are formed. Three of these pixels are made transparent to allow the transmission of cyan light with a peak wavelength of 490–505 nm transmitted from the lower C-array pixels, red light with a peak wavelength of 630–655 nm converted by a red phosphor and transmitted from the lower C-array pixels, and blue light with a peak wavelength of 455–470 nm emitted from the B-array pixels without absorption. The remaining two pixels are formed to use a second green phosphor and a third green phosphor, respectively, to convert the blue light with a peak wavelength of 455–470 nm into green light with a peak wavelength of 515–530 nm and green light with a peak wavelength of 540–555 nm. In contrast, in the case corresponding to… Figure 6 In the case of the upper optical film 445a of the panchromatic module 100B' in (b), similarly, a total of five pixels are formed, two of which are formed to be transparent so that the cyan light with a peak wavelength of 490~505nm transmitted from the lower C array pixels and the blue light with a peak wavelength of 455~470nm emitted from the upper B array pixels can pass through without absorption. The other pixel is formed as a red phosphor that converts the cyan light with a peak wavelength of 490~505nm transmitted from the lower C array pixels into red light with a peak wavelength of 630~655nm. The remaining two pixels are as described above. Figure 6 (a) is formed as two types of second and third green phosphors, which respectively form blue light with a peak wavelength of 455~470nm into green light with a peak wavelength of 515~530nm and green light with a peak wavelength of 540~555nm.

[0071] Based on Figures 5(a), 5(b), and above Figure 6The embodiment fabricates a full-color module 100 based on RGCB pixel 111-1 or RGGCB pixel 111-2 using a hybrid micro-LED array 110, 210, 310, 410, and arranges and expands such modules to complete a UWCG-level micro-LED display panel 1000 of various sizes and shapes.

[0072] As described above, a display panel constructed using the RGCB pixel-based full-color module 100 of the present invention, which utilizes four color light sources—red (R), green (G), cyan (C), and blue (B)—within a specific wavelength range, can display a richer color gamut than the UWCG color gamut, which is wider than that of BT. 2020 WCG. Furthermore, such a full-color module utilizes one or more LED arrays fabricated monolithically, thereby enabling the production of UWCG-grade LED display panels of various sizes at a high production speed. In this case, when using hybrid LEDs, luminous efficiency is higher, and heat generation due to leakage current is reduced, thus improving durability. Moreover, by vertically stacking multiple LED arrays, integration can be increased, thereby improving not only brightness and color perception but also resolution.

[0073] The above description relates to specific embodiments of the present invention. These embodiments are disclosed for illustrative purposes and are not intended to limit the scope of the invention. Rather, they should be understood that those skilled in the art can make various changes and modifications without departing from the essence of the invention.

[0074] Specifically, in addition to Figures 4 to 6 In addition to the embodiments described above, RGCB pixels using LED arrays capable of achieving a UWCG (Ultra Wide Color Gamut) color gamut can be implemented in a variety of ways. Furthermore, depending on the circumstances, the number of specific color light sources or even the shape of the pixels in the RGCB pixels can be changed for other purposes such as enhancing the brightness of color light sources within the same wavelength range.

[0075] For example, as mentioned above Figure 4 As shown in Figures 5(a) and 5(b), as an example of increasing the brightness of insufficient red light while achieving the UWCG-1 color gamut, a full-color module based on RGCB pixels with the following characteristics can be suggested as an example of a variation that can be implemented within the scope of the present invention: the unit pixel of the LED array consists of three blue LEDs and two cyan LEDs. Two of the three blue LEDs are respectively combined with a first green phosphor for converting blue light into green light with a peak wavelength of 520~535nm and a red phosphor for converting blue light into red light with the corresponding peak wavelength. One of the two cyan LEDs is combined with another red phosphor for converting cyan light into red light with the corresponding peak wavelength.

[0076] Furthermore, when such a variant is configured as a multi-level LED array layer of B and C arrays, as in the embodiments of Figures 5(a) and 5(b), it can be considered that the wavelength range of each color light source is set to the UWCG-1 color gamut, and the number of light sources and the planar shape of the pixels are implemented in a manner similar to... Figure 4 (b) and Figure 6 In this case, based on the number of light sources, the pixels are RRGCB pixel structures, unlike the BG pixel patterns in Figures 5(a) and 5(b). Figure 6 The BGG pixel pattern is used, and the LEDs in the B array are arranged along the BGR pixel pattern.

[0077] In such a variation, for each of the optical films provided in the B and C arrays, the lower optical film can be constructed in the same manner as... Figure 6 In the same manner, with the upper optical film, a total of five pixels are formed, and as... Figure 6 It will depend on the morphology of the underlying optical film. Specifically, (i) for such Figure 6 (a) The lower optical film, three pixels of the upper optical film are made transparent, and the remaining two pixels are formed as a first green phosphor for converting blue light with a peak wavelength of 455~470nm into green light with a peak wavelength of 520~535nm and a red phosphor for converting it into red light with a peak wavelength of 630~655nm; (ii) For such Figure 6 In (b), the lower optical film has two pixels of the upper optical film that are transparent. The two pixels are formed as a first green phosphor that converts blue light with a peak wavelength of 455~470nm into green light with a peak wavelength of 520~535nm and a red phosphor that converts it into red light with a peak wavelength of 630~655nm. The remaining pixel is formed as another red phosphor that converts cyan light with a peak wavelength of 490~505nm transmitted from the lower C array into red light with a peak wavelength of 630~655nm.

[0078] Therefore, all such modifications and alterations can be understood to fall within the scope of the invention disclosed in the claims or their equivalents.

Claims

1. A panchromatic module based on RGCB pixels, comprising four color light sources: red (R), green (G), cyan (C), and blue (B), characterized in that the RGCB pixel-based panchromatic module includes: A red light source with a peak wavelength of 630~655nm; Green light source with a peak wavelength of 515~555nm; A cyan light source with a peak wavelength of 490~505nm; and Blue light source with a peak wavelength of 455~470nm The color light source is composed of an LED array layer, which is a structure stacked on top of a TFT layer and connected to electrodes. The color light source is a structure consisting of multiple pairs of LED array layers and TFT layers stacked on top of each other, and the pattern of the RGCB pixel is a pattern formed by orthographically projecting and combining the pixel patterns of each of the multiple stacked LED array layers.

2. The panchromatic module based on RGCB pixels according to claim 1, characterized in that, The green light source includes a first green light source with a peak wavelength of 520~535nm.

3. The panchromatic module based on RGCB pixels according to claim 1, characterized in that, The green light source includes a second green light source with a peak wavelength of 515~530nm and a third green light source with a peak wavelength of 540~555nm.

4. The panchromatic module based on RGCB pixels according to claim 1, characterized in that, The blue light source is a blue LED made of GaN, or a blue hybrid LED with a p-type layer made of ZnO and GaN.

5. The panchromatic module based on RGCB pixels according to claim 1, characterized in that, The cyan light source is a cyan LED made of GaN, or a cyan hybrid LED with a p-type layer made of ZnO and GaN.

6. The full-color module based on RGCB pixels according to claim 2, characterized in that, The first green light source is constructed by combining a first green phosphor with a blue LED, which is an LED made of GaN or a hybrid LED with a p-type layer made of ZnO and GaN. The first green phosphor converts blue light into green light with a corresponding peak wavelength.

7. The panchromatic module based on RGCB pixels according to claim 3, characterized in that, The second green light source and the third green light source are respectively constructed by combining the second green phosphor and the third green phosphor with a blue LED. The blue LED is an LED made of GaN or a hybrid LED with a p-type layer made of ZnO and GaN. The second green phosphor and the third green phosphor respectively convert blue light into green light with their respective peak wavelengths.

8. The panchromatic module based on RGCB pixels according to claim 1, characterized in that, The red light source is constructed by combining a red phosphor with a cyan LED. The cyan LED is an LED made of GaN or a hybrid LED with a p-type layer made of ZnO and GaN. The red phosphor converts cyan light into red light with a corresponding peak wavelength.

9. The panchromatic module based on RGCB pixels according to claim 1, characterized in that, The red light source is constructed by combining a red phosphor with a blue LED. The blue LED is an LED made of GaN or a hybrid LED with a p-type layer made of ZnO and GaN. The red phosphor converts blue light into red light with a corresponding peak wavelength.

10. The panchromatic module based on RGCB pixels according to claim 1, characterized in that, Each pixel of the LED array includes two blue LEDs and two cyan LEDs. One of the two blue LEDs is combined with a first green phosphor for converting blue light into green light with a peak wavelength of 520~535nm. One of the two cyan LEDs is combined with a red phosphor for converting cyan light into red light with a corresponding peak wavelength.

11. The panchromatic module based on RGCB pixels according to claim 1, characterized in that, Each pixel of the LED array includes three blue LEDs and two cyan LEDs. Two of the three blue LEDs are respectively combined with a second green phosphor for converting blue light into green light with a peak wavelength of 515~530nm and a third green phosphor for converting blue light into green light with a peak wavelength of 540~555nm. One of the two cyan LEDs is combined with a red phosphor for converting cyan light into red light with a corresponding peak wavelength.

12. The panchromatic module based on RGCB pixels according to claim 1, characterized in that, Each pixel of the LED array includes three blue LEDs and two cyan LEDs. Two of the three blue LEDs are respectively combined with a first green phosphor for converting blue light into green light with a peak wavelength of 520~535nm and a red phosphor for converting blue light into red light with the corresponding peak wavelength. One of the two cyan LEDs is combined with another red phosphor for converting cyan light into red light with the corresponding peak wavelength.

13. The panchromatic module based on RGCB pixels according to claim 1, characterized in that, The plurality of LED array layers include: A blue LED array layer arranging LEDs according to a BG pixel pattern or a BGR pixel pattern; and A blue LED array layer with LEDs arranged according to an RC pixel pattern.

14. The panchromatic module based on RGCB pixels according to any one of claims 1 to 13, characterized in that, Also includes: An optical film is disposed on the light-emitting side of the LED array layer. In the optical film, visible light is opaque except for the pixel pattern corresponding to the pixels of the relevant LED array layer.

15. The panchromatic module based on RGCB pixels according to claim 14, characterized in that, A portion of the pixel pattern of the optical film is formed with a phosphor for converting blue light into green light, or a phosphor for converting blue or cyan light into red light.

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