Display device using light emitting device

Abstract

The present invention is applicable to technical fields related to display devices, and, for example, relates to a display device using a micro LED (Light Emitting Diode). The present invention comprises: a wiring substrate in which a plurality of unit pixel regions are defined; a first wiring electrode and a second wiring electrode arranged on the wiring substrate; a first electrode pad and a second electrode pad respectively connected to the first wiring electrode and the second wiring electrode; and a light-emitting element that forms a subpixel by being electrically connected to the first electrode pad and the second electrode pad in each of the unit pixel regions. The light-emitting element comprises: a first light-emitting element located in the first pixel region and installed in a first arrangement; and a second light-emitting element located in a second pixel region adjacent to the first pixel region and installed in a second arrangement symmetrical to the first arrangement. The second wiring electrode may be disposed on the same layer as the light-emitting element.

Description

Technology Field

[0001] The present invention is applicable to the field of technology related to display devices, and, for example, relates to a display device using a micro LED (Light Emitting Diode). Background Technology

[0002] Recently, display devices with excellent characteristics such as thinness and flexibility are being developed in the field of display technology. Currently, the major commercially available displays are represented by LCD (Liquid Crystal Display) and OLED (Organic Light Emitting Diodes).

[0003] Meanwhile, light-emitting diodes (LEDs) are semiconductor light-emitting devices well known for converting electric current into light. Starting with the commercialization of red LEDs using GaAsP compound semiconductors in 1962, they have been used as light sources for display images in electronic devices, including information and communication equipment, along with green LEDs of the GaP:N series.

[0004] Recently, these light-emitting diodes (LEDs) have been gradually miniaturized and manufactured into micrometer-sized LEDs, which are being used as pixels in display devices or as flat lighting.

[0005] Sapphire, which is used as a substrate for growing gallium nitride-based semiconductors, has tilted crystal planes. For example, the R-plane has a crystal plane tilted toward the m-axis. Typically, sapphire can have an R-plane as a growth plane. Since the R-plane has a tilted plane relative to the hexagonal prism crystal shape, the sapphire substrate and the gallium nitride-based semiconductor grown on the crystal plane of the sapphire substrate can have such a tilted angle.

[0006] In addition, such a tilt angle can also be formed due to the cutting of the sapphire substrate in the direction of the crystal plane after the light-emitting element is formed with a gallium nitride-based semiconductor on the sapphire substrate.

[0007] Accordingly, when a light-emitting element is mounted on a wiring board in a general arrangement and emits light, a display device can be formed by forming individual subpixels with an asymmetric light distribution with respect to the direction connecting two electrode pads for a single light-emitting element.

[0008] As such, if a display device is constructed with individual subpixels having an asymmetric light distribution, a problem may arise where the color appears different depending on the viewing direction when viewing the display device from the outside.

[0009] As displays utilizing light-emitting elements such as LEDs advance, the demand for narrow-pitch displays (the distance between LED light sources) is increasing. Implementing narrow-pitch displays requires high-density design technology for LED light sources; consequently, PCBs forming the wiring substrates tend to be designed and implemented in multiple layers.

[0010] In such a multilayer wiring board, electrical connections between each layer can be made through via holes. In this case, the via holes can usually be located overlapping with the pad area where the LED light source is located (transferred).

[0011] If the via hole is spaced apart from the pad at a certain distance, the shape and width of the pad may not be affected by the via hole; however, as the pitch becomes narrower due to the high image quality expected as described above, there is less spatial room to position the via hole further away from the pad. Consequently, the via hole may end up overlapping with the pad.

[0012] For example, while a pad connected to a common electrode can be connected using a single via hole, a pad connected to a pixel electrode must be connected to an RGB LED forming each subpixel, so the density of via holes for the common electrode and the pixel electrode may differ. For example, the density of via holes connected to the pixel electrode increases by approximately three times or more, and consequently, the probability of a situation occurring where via holes overlap with pads may increase.

[0013] When vias overlap with pads, the shape and area of ​​the pad connected to the negative (-) electrode and the pad connected to the positive (+) electrode may be formed differently depending on the density of the via holes.

[0014] Accordingly, when applying solder for transfer (bonding) of the LED onto the pad, the amount of solder may vary. Consequently, the amount of solder on both pads may differ. This can cause a difference in the height of the solder. As a result, the left and right heights of the LED may differ, and the LED may be transferred tilted to one side rather than flat. When the LED is transferred in this tilted manner, the direction of light emission from the light source is distorted, causing the light intensity to change depending on the viewing angle, which may result in image quality defects.

[0015] Therefore, measures to resolve these problems are required. The problem to be solved

[0016] The technical problem to be solved by the present invention is to provide a display device using a light-emitting element capable of offsetting the skewed light distribution of the light-emitting element caused by the crystallinity of the light-emitting element.

[0017] In addition, we aim to provide a display device using a light-emitting element that can resolve the problem of colors appearing differently depending on the viewing direction when viewing the display device from the outside.

[0018] In addition, we aim to provide a display device using a light-emitting element capable of reducing parasitic capacitance arising from the difference in electrical polarity of the light-emitting elements.

[0019] In addition, we aim to provide a display device using a light-emitting element capable of canceling out the electric field generated from the difference in electrical polarity of the light-emitting elements.

[0020] In addition, according to one embodiment of the present invention, a display device using a light-emitting element is provided that can correct the difference in color tone of the display perceived from the left and right sides by visually reinforcing an area with weak color tone when viewing the display from one direction.

[0021] Meanwhile, we aim to provide a display device using a light-emitting element that can reduce the number of via holes.

[0022] Accordingly, we aim to provide a display device using a light-emitting element that can increase the degree of freedom of pixel placement and avoid the influence of via holes when having a high-density pixel placement due to increased resolution. means of solving the problem

[0023] As one aspect of the present invention for achieving the above-described objective, the present invention comprises: a wiring substrate having a plurality of unit pixel regions defined therein; a first wiring electrode and a second wiring electrode arranged on the wiring substrate; a first electrode pad and a second electrode pad respectively connected to the first wiring electrode and the second wiring electrode; and a light-emitting element installed to be electrically connected to the first electrode pad and the second electrode pad in each of the unit pixel regions to form a subpixel, wherein the light-emitting element comprises: a first light-emitting element located in the first pixel region and installed in a first arrangement; and a second light-emitting element located in the second pixel region adjacent to the first pixel region and installed in a second arrangement symmetrical to the first arrangement, and the second wiring electrode may be disposed on the same layer as the light-emitting element.

[0024] In an exemplary embodiment, the first wiring electrode may be disposed on a different layer from the light-emitting element through a via hole connected to the first electrode pad.

[0025] In an exemplary embodiment, the first electrode pad may include a pad extension.

[0026] In an exemplary embodiment, the pad extension may include a first extension; and a second extension that extends further than the first extension.

[0027] In an exemplary embodiment, the via hole may be located in the pad extension.

[0028] In an exemplary embodiment, the pad extensions may be connected to each other with respect to adjacent pixel regions.

[0029] In an exemplary embodiment, the pad extensions may be connected to each other with respect to pixel regions facing each other.

[0030] In an exemplary embodiment, with respect to the interconnected pad extensions, the via hole may be shared between the first pixel region and the second pixel region.

[0031] In an exemplary embodiment, the first arrangement and the second arrangement may be arrangements in which the positions of the electrodes of the first light-emitting element and the second light-emitting element are symmetrical to each other.

[0032] In an exemplary embodiment, a second wiring electrode corresponding to the first pixel area and an adjacent second wiring electrode corresponding to the second pixel area may be positioned symmetrically with respect to the center between the first pixel area and the second pixel area.

[0033] In an exemplary embodiment, the first pixel region and the second pixel region may be paired between adjacent second wiring electrodes.

[0034] In an exemplary embodiment, the first light-emitting element and the second light-emitting element can emit light of the same color.

[0035] In an exemplary embodiment, the first pixel area may be located in multiple places along the second wiring electrode.

[0036] In an exemplary embodiment, the second wiring electrode may be a common electrode commonly connected to a plurality of first pixel regions.

[0037] In an exemplary embodiment, the electric field generated from the difference in electrical polarity between the first light-emitting element and the second light-emitting element can be canceled out by the first arrangement and the second arrangement. Effects of the invention

[0038] First, according to one embodiment of the present invention, the skewed light distribution of the light-emitting elements resulting from the crystallinity of the light-emitting elements can be canceled out. That is, the asymmetric light distribution of the light-emitting elements can be canceled out.

[0039] Accordingly, the problem of colors appearing differently depending on the viewing direction when looking at the display device from the outside can be resolved.

[0040] Meanwhile, according to one embodiment of the present invention, parasitic capacitance arising from the difference in electrical polarity of light-emitting elements can be reduced.

[0041] Meanwhile, ghosting phenomena that may occur due to such parasitic capacitance can be improved.

[0042] Meanwhile, according to one embodiment of the present invention, the electric field generated from the difference in electrical polarity of the light-emitting elements can be canceled out.

[0043] Meanwhile, according to one embodiment of the present invention, when viewing the display from one direction, the color difference of the display perceived from the left and right can be corrected by visually reinforcing the area with weak color. Accordingly, the effect of enhancing the color viewing angle at the final product stage of the display device can be obtained.

[0044] Meanwhile, one side wiring electrode is placed on the same layer as the light-emitting element, that is, on the outermost layer, so that the number of via holes can be reduced.

[0045] Accordingly, the degree of freedom for pixel placement can be increased, and in the case of high-density pixel placement due to increased resolution, it may not be affected by via holes.

[0046] Furthermore, according to another embodiment of the present invention, there are additional technical effects not mentioned herein. Those skilled in the art will understand this from the full context of the specification and drawings. Brief explanation of the drawing

[0047] FIG. 1 is a schematic diagram of a display device using a light-emitting element according to one embodiment of the present invention. FIG. 2 is a schematic diagram showing the arrangement of subpixels of a display device using a light-emitting element according to one embodiment of the present invention. FIG. 3 is a circuit diagram showing the arrangement of subpixels of a display device using a light-emitting element according to one embodiment of the present invention. Figure 4 is a schematic diagram showing the arrangement of subpixels of a display device using a light-emitting element according to a comparative example. Figure 5 is a circuit diagram showing the subpixel arrangement of a display device using a light-emitting element according to a comparative example. FIG. 6 is a schematic diagram showing the effect of the subpixel arrangement of a display device using a light-emitting element according to one embodiment of the present invention. FIG. 7 is a plan view showing the arrangement of wiring electrodes of a display device using a light-emitting element according to a comparative example. FIG. 8 is a plan view showing the arrangement of wiring electrodes of a display device using a light-emitting element according to a comparative example in more detail. FIG. 9 is a plan view showing the arrangement of wiring electrodes of a display device using a light-emitting element according to a first embodiment of the present invention. Figure 10 is a detailed view of part A of Figure 9. FIG. 11 is a plan view showing the arrangement of wiring electrodes of a display device using a light-emitting element according to a second embodiment of the present invention. Figure 12 is a detailed view of part B of Figure 11. FIG. 13 is a schematic diagram showing the operation of a display device using a light-emitting element according to a second embodiment of the present invention. FIG. 14 is a schematic diagram showing a specific example of a subpixel arrangement of a display device using a light-emitting element according to one embodiment of the present invention. FIG. 15 is a schematic diagram showing another specific example of a subpixel arrangement of a display device using a light-emitting element according to one embodiment of the present invention. Figure 16 is a diagram schematically showing the subpixel arrangement of Figures 14 and 15. FIG. 17 is a schematic diagram showing the process of forming a subpixel arrangement according to FIG. 14. FIG. 18 is a side view showing an individual light-emitting element of a display device using a light-emitting element according to one embodiment of the present invention. FIG. 19 is a schematic diagram showing the tilt angle of an individual light-emitting element of a display device using a light-emitting element according to one embodiment of the present invention. Figure 20 schematically shows the sapphire crystal planes and crystal orientations. FIG. 21 is a side view showing light-emitting elements of a display device using light-emitting elements according to one embodiment of the present invention. FIG. 22 is a schematic diagram showing the tilt angles of light-emitting elements of a display device using light-emitting elements according to one embodiment of the present invention. Specific details for implementing the invention

[0048] Hereinafter, embodiments disclosed in this specification will be described in detail with reference to the attached drawings. Identical or similar components, regardless of drawing symbols, are assigned the same reference number, and redundant descriptions thereof will be omitted. The suffixes "module" and "part" used for components in the following description are assigned or used interchangeably solely for the ease of drafting the specification and do not inherently possess distinct meanings or roles. Furthermore, when describing the embodiments disclosed in this specification, detailed descriptions of related prior art are omitted if it is determined that such detailed descriptions could obscure the essence of the embodiments disclosed in this specification. Additionally, it should be noted that the attached drawings are intended only to facilitate understanding of the embodiments disclosed in this specification and should not be interpreted as limiting the technical concept disclosed in this specification.

[0049] Furthermore, for the convenience of explanation, each drawing is described, but it is also within the scope of the present invention that a person skilled in the art implements other embodiments by combining at least two drawings.

[0050] Furthermore, when elements such as layers, regions, or substrates are referred to as existing "on" other components, it can be understood that this means they exist directly on the other elements or that there may be an intermediate element between them.

[0051] The concept of a display device as described in this specification includes all display devices that display information as a unit pixel or a set of unit pixels. Therefore, it is not limited to finished products but can also be applied to components. For example, a panel corresponding to a component of a digital TV also independently corresponds to a display device as defined in this specification. Finished products may include mobile phones, smartphones, laptop computers, digital broadcasting terminals, PDAs (personal digital assistants), PMPs (portable multimedia players), navigation systems, Slate PCs, Tablet PCs, Ultra Books, digital TVs, desktop computers, etc.

[0052] However, those skilled in the art will readily understand that the configuration according to the embodiments described in this specification may be applied to displayable devices, even in the form of new products developed in the future.

[0053] In addition, the light-emitting elements mentioned in this specification include concepts such as LEDs, mini LEDs, micro LEDs, etc., and may be used interchangeably.

[0054] FIG. 1 is a schematic diagram of a display device using a light-emitting element according to one embodiment of the present invention.

[0055] Referring to FIG. 1, a display device (10) may be configured such that individual unit pixel areas (101) are partitioned on a wiring board (100), and a plurality of light-emitting elements (200: 210, 220, 230) are installed within the unit pixel areas (101).

[0056] Here, individual light-emitting elements (210, 220, 230) installed in a unit pixel area (101) may substantially correspond to subpixels. For example, three subpixels may be combined to form a single pixel. In FIG. 1, the three light-emitting elements (210, 220, 230) may correspond to red, green, and blue light-emitting elements, respectively.

[0057] Each light-emitting element (210, 220, 230) can be electrically connected to a pair of electrode pads (130, 140 / 131, 141 / 132, 142). In this case, for example, the electrode pads (130, 131, 132: hereinafter, first electrode pads) arranged in one direction in FIG. 1 can be connected to a first wiring electrode (121, 122, 123; signal electrode or data electrode).

[0058] Additionally, the electrode pads (140, 141, 142: hereinafter, second electrode pads) arranged in the other direction may be connected to the second wiring electrode (124; common electrode or scan electrode). However, the opposite is also possible. In FIG. 1, the signal electrodes (121, 122, 123) and the common electrode (124) are omitted due to the arrangement of the electrodes and electrode pads.

[0059] Meanwhile, depending on the case, the first electrode pad (130, 131, 132) may correspond to the signal electrode (121, 122, 123), and the second electrode pad (140, 141, 142) may correspond to the common electrode (124).

[0060] Hereinafter, the drawing symbols for electrode pads and wiring electrodes will be described interchangeably. That is, electrode pads and wiring electrodes can be described using the same drawing symbol.

[0061] In this way, a unit subpixel can be defined at the point where the first wiring electrode (121, 122, 123) and the second wiring electrode (124) intersect each other.

[0062] Meanwhile, when the first wiring electrode (121, 122, 123) is a signal electrode (or data electrode), such first wiring electrode (121, 122, 123, or first electrode pad (130, 131, 132)) can be connected to a TFT layer (120) equipped with a thin film transistor (TFT). Accordingly, each light-emitting element (210, 220, 230) can be driven by switching drive by such a TFT layer (120).

[0063] In FIG. 1, the TFT layer (120) is briefly shown as a single layer, but the TFT layer (120) may include a plurality of TFT regions capable of performing switching operations. For example, each TFT region may include a gate electrode, a source electrode, a drain electrode, an insulating layer located between them, a via electrode that can be connected to a first wiring electrode (121, 122, 123, or a first electrode pad (130, 131, 132)). A detailed description thereof is omitted. Each of these TFT regions may be connected to a respective light-emitting element (210, 220, 230).

[0064] A plurality of light-emitting elements (200; 210, 220, 230) can be electrically connected on these wiring electrodes (121, 122, 123, 124) to form individual subpixels and installed.

[0065] As mentioned above, the light-emitting element (200) may include a red light-emitting element (210), a green light-emitting element (220), and a blue light-emitting element (230), and these three light-emitting elements (210, 220, 230) may form individual subpixels and be repeatedly positioned on a wiring substrate (100). The light-emitting elements (210, 220, 230) may include at least one of an organic light-emitting element and an inorganic light-emitting element. For example, the light-emitting elements (210, 220, 230) may be inorganic semiconductor light-emitting diodes (LEDs).

[0066] Such semiconductor light-emitting elements (LED; 200) may have a size in the order of micrometers (㎛). A size in the order of micrometers (㎛) may mean that the width of at least one surface of the light-emitting element (200) may have a size of several to several hundred micrometers (㎛).

[0067] A TFT layer (120) may be located on a substrate (110), and an insulating layer (150) may be covered on the TFT layer (120). This insulating layer (150) may cover the connection portion between the wiring electrodes (121, 122, 123, 124), the electrode pads (130, 131, 132 / 140, 141, 142) and the light-emitting elements (210, 220, 230).

[0068] For example, individual light-emitting elements (210, 220, 230) can be separated from each other by a partition (160). Additionally, a cover layer (170) may be positioned on the light-emitting elements (210, 220, 230) and the partition (160).

[0069] As described above, the light-emitting elements (210, 220, 230) can form individual subpixels and be repeatedly positioned on the wiring substrate (100). For example, each pixel area (101) can be repeatedly arranged on the wiring substrate (100).

[0070] At this time, the pixel area (101) may be repeatedly positioned along a line of a data electrode (121, 122, 123; first wiring electrode) or a line of a scan electrode (124; second wiring electrode) in the longitudinal direction. For example, in FIG. 1, a red light-emitting element (210), a green light-emitting element (220), and a blue light-emitting element (230) may be repeatedly positioned along the left-right direction. For example, a red light-emitting element of an adjacent pixel area may be positioned to the right of the blue light-emitting element (230).

[0071] Meanwhile, another data electrode (first wiring electrode) line or scan electrode (second wiring electrode) line may be located adjacent to one data electrode (first wiring electrode) line or scan electrode (second wiring electrode) line in parallel (see FIG. 8). At this time, a pixel area (102; see FIG. 8) having the same arrangement of light-emitting elements (210, 220, 230) as the pixel area (101) may be located in the adjacent data electrode (first wiring electrode) line or scan electrode (second wiring electrode) line.

[0072] In this case, light-emitting elements having the same color may be located adjacently in adjacent pixel regions. For example, red light-emitting elements (210), green light-emitting elements (220), and blue light-emitting elements (230) may be repeatedly located along the data electrode (first wiring electrode) line or the scan electrode (second wiring electrode) line, but light-emitting elements having the same color may be repeatedly located in a direction perpendicular to the data electrode (first wiring electrode) line or the scan electrode (second wiring electrode) line.

[0073] At this time, according to one embodiment of the present invention, two adjacent light-emitting elements may have different arrangements. For example, referring to FIG. 1, a red light-emitting element (210) and a green light-emitting element (220) adjacent to the red light-emitting element (210) may have different arrangements.

[0074] For example, a red light-emitting element (210) may have a first type electrode, e.g., an N electrode, positioned on the first wiring electrode (130), and a green light-emitting element (220) may have a second type electrode, e.g., a P electrode, positioned on the first wiring electrode (131). Such different arrangements may also be made between the green light-emitting element (220) and the blue light-emitting element (230).

[0075] That is, the red light-emitting element (210) and the green light-emitting element (220) adjacent to the red light-emitting element (210) may have a symmetrical arrangement with respect to the electrode positions of each light-emitting element (210, 220).

[0076] Meanwhile, a light-emitting element (e.g., a red light-emitting element (210)) located in one pixel area (101) and a light-emitting element (e.g., a red light-emitting element (210)) located in an adjacent pixel area (102) may have an arrangement that is symmetrical to each other with respect to the electrode position.

[0077] In other words, on the wiring board (100), a first light-emitting element (210) located in a first pixel area (101) and installed in a first arrangement, and a second light-emitting element (210) located in a second pixel area (102) adjacent to the first pixel area (101) and installed in a second arrangement symmetrical to the first arrangement may be located.

[0078] By the first and second arrangements of such light-emitting elements (210), parasitic capacitance caused by the difference in electrical polarity between the first light-emitting element and the second light-emitting element can be reduced.

[0079] In addition, by the first and second arrangements of these light-emitting elements (210), the electric field generated from the difference in electrical polarity between the first light-emitting element and the second light-emitting element can be canceled out.

[0080] The light-emitting elements (210) having these different arrangements and their effects will be described in detail later.

[0081] FIG. 2 is a schematic diagram showing the subpixel arrangement of a display device using a light-emitting element according to an embodiment of the present invention. FIG. 3 is a circuit diagram showing the subpixel arrangement of a display device using a light-emitting element according to an embodiment of the present invention.

[0082] FIG. 4 is a schematic diagram showing the subpixel arrangement of a display device using a light-emitting element according to a comparative example. FIG. 5 is a circuit diagram showing the subpixel arrangement of a display device using a light-emitting element according to a comparative example.

[0083] Referring to FIG. 2, a state is illustrated in which adjacent first light-emitting elements (230a) and second light-emitting elements (230b) are positioned with different arrangements, namely a first arrangement and a second arrangement. Additionally, the second light-emitting element (230b) and third light-emitting element (230c) may also be positioned with different arrangements. Referring to FIG. 3, light-emitting elements (D1 * , D2 * , D3 * , ... , Dn * It can be seen that ) is connected with alternating opposite arrangements.

[0084] For example, the first light-emitting element (230a) and the third light-emitting element (230c) may be positioned with a first arrangement, and the second light-emitting element (230b) located between the first light-emitting element (230a) and the third light-emitting element (230c) may be positioned with a second arrangement.

[0085] At this time, the first light-emitting element (230a), the second light-emitting element (230b), and the third light-emitting element (230c) may all be light-emitting elements that emit the same color. For example, the first light-emitting element (230a), the second light-emitting element (230b), and the third light-emitting element (230c) may all be blue light-emitting elements.

[0086] Here, the first arrangement may be an arrangement in which the N electrode (235) is located on the left side and the P electrode (237) is located on the right side in FIG. 2. In each light-emitting element (230a, 230b, 230c), a semiconductor layer (232) is located on a substrate (231), and a first type electrode, e.g., an N type electrode (235), and a second type electrode, e.g., a P type electrode (237), may be located in contact with the semiconductor layer (232).

[0087] That is, each light-emitting element (230a, 230b, 230c) may include a substrate (231), a semiconductor layer (232), a first type electrode (235), and a second type electrode (237). At this time, each light-emitting element (230a, 230b, 230c) may have different arrangements with respect to the direction connecting the first type electrode (235) and the second type electrode (237).

[0088] Referring to FIG. 2, each light-emitting element (230a, 230b, 230c) may have an asymmetric light distribution (a, b) with respect to the direction connecting the first type electrode (235) and the second type electrode (237). For example, the first light-emitting element (230a) and the third light-emitting element (230c) may have a light distribution (a) skewed to the left. This corresponds to the first arrangement. Additionally, the second light-emitting element (230b) located between the first light-emitting element (230a) and the third light-emitting element (230c) may have a light distribution (b) skewed to the right. This corresponds to the second arrangement.

[0089] This may be a result of the material properties of at least one of the substrate (231) and the semiconductor layer (232). For example, this phenomenon may occur because the crystal structure of at least one of the substrate (231) and the semiconductor layer (232) has a tilted shape. This will be described in detail later.

[0090] As a comparative example, FIG. 4 illustrates the case where each light-emitting element (23a, 23b, 23c) forms the same arrangement (b) and the corresponding light distribution (b). For example, the light-emitting element (23c) includes a semiconductor layer (23c-2) located on a substrate (23c-1), and a first type electrode (23c-3) and a second type electrode (23c-4) connected to the semiconductor layer (23c-2). Referring to FIG. 5, it can be seen that the light-emitting elements (D1, D2, D3, ..., Dn) are all connected with the same arrangement.

[0091] As illustrated in FIG. 4, if a display device is formed by individual subpixels in which each light-emitting element (23a, 23b, 23c) has an asymmetric light distribution (b) with respect to the direction connecting the first type electrode (23c-3) and the second type electrode (23c-4), a problem may arise where the color appears different depending on the viewing direction when viewing the display device from the outside.

[0092] The polarity arrangement of such light-emitting elements (23a, 23b, 23c) is such that the first type electrode (23c-3) and the second type electrode (23c-4) are repeated sequentially, and unintended parasitic capacitance may occur due to the electric field formed by the polarity difference between the first type electrode (23c-3) and the second type electrode (23c-4) of each light-emitting element (23a, 23b, 23c) (or between the signal electrode / common electrode connected thereto).

[0093] As a result, even when the electric field is eliminated, the discharge of parasitic capacitance does not occur normally, which may cause neighboring light-emitting elements to turn on unintentionally. For example, when D3 is in the ON state, D1 and D2, which should be in the OFF state, may unintentionally remain in the ON state. This effect can accumulate for the entire number of light-emitting elements (23a, 23b, 23c), and ultimately, a ghosting phenomenon may appear in the display product unit.

[0094] However, as in one embodiment of the present invention, if adjacent light-emitting elements (230a, 230b, 230c) have different arrangements with respect to the direction connecting the first type electrode (235) and the second type electrode (237), this problem can be solved.

[0095] As an exemplary embodiment, FIG. 2 illustrates a state in which the light distribution (a, b) of each light-emitting element (230a, 230b, 230c) is skewed toward the N-type electrode (235). However, this is merely an example, and the light distribution of all light-emitting elements (230a, 230b, 230c) is not skewed toward the N-type electrode (235). That is, conversely, the light distribution of each light-emitting element (230a, 230b, 230c) may be skewed toward the P-type electrode (237).

[0096] Therefore, if the first type electrode (235) and the second type electrode (237) of adjacent light-emitting elements (230a, 230b, 230c) have different arrangements in the direction of connection, these skewed light distributions (a, b) can be canceled out. That is, the problem of the color appearing differently depending on the viewing direction when looking at the display device from the outside can be resolved.

[0097] By the first and second arrangements of such light-emitting elements (230a, 230b, 230c), parasitic capacitance resulting from the difference in electrical polarity of the light-emitting elements (230a, 230b, 230c) can be reduced.

[0098] In addition, by the first and second arrangements of these light-emitting elements (230a, 230b, 230c), the electric field generated from the difference in electrical polarity of the light-emitting elements (230a, 230b, 230c) can be canceled out.

[0099] FIG. 6 is a schematic diagram showing the effect of the subpixel arrangement of a display device using a light-emitting element according to one embodiment of the present invention.

[0100] Referring to FIG. 6, light-emitting elements (230b, 230c) formed by being installed on a wiring board (100) and forming a subpixel may be provided.

[0101] At this time, referring to the lower side of FIG. 6(B), the wiring board (100) includes wiring electrodes (123, 124) including a first wiring electrode (123) and a second wiring electrode (124) arranged on the wiring board (100) as described above with reference to FIG. 1, and in each unit pixel area, a light-emitting element (230b, 230c) can be installed by being electrically connected to the first wiring electrode (123) and the second wiring electrode (124). That is, the subpixel arrangement of FIG. 6 may correspond to the case of the blue light-emitting element (230) of FIG. 1.

[0102] Here, referring to FIGS. 6(A) and (B) together, the light-emitting element (230b, 230c) may be configured to include a first light-emitting element (230b) located in a first pixel area and installed in a first arrangement, and a second light-emitting element (230c) located in a second pixel area adjacent to the first pixel area and installed in a second arrangement symmetrical to the first arrangement.

[0103] The first light-emitting element (230b) and the second light-emitting element (230c) may include a substrate (231), a semiconductor layer (232), a first type electrode (235), and a second type electrode (237). In this case, the first light-emitting element (230b) and the second light-emitting element (230c) may have different arrangements with respect to the direction connecting the first type electrode (235) and the second type electrode (237).

[0104] Accordingly, the light distribution (a) skewed to one side by the first arrangement and the light distribution (b) skewed to the other side by the second arrangement can be combined to have an unskewed light distribution (c) toward the center. That is, the asymmetric light distribution can be offset by the first arrangement of the first light-emitting element (230b) and the second arrangement of the second light-emitting element (230c).

[0105] At this time, as described above, the first light-emitting element (230b) and the second light-emitting element (230c) may be light-emitting elements that emit the same color located in adjacent pixel regions, for example, blue light-emitting elements.

[0106] When a constant voltage is applied to a light-emitting diode (LED) with a PN junction structure, charges and holes recombine in the region near where the P-region and N-region meet to emit light. At this time, the part that emits the most light is located in a different area rather than in the center of where the P-region and N-region meet. Therefore, if a display is manufactured using such an LED, the color may appear different depending on the viewing direction.

[0107] However, as explained above, if the first arrangement of the first light-emitting element (230b) and the second arrangement of the second light-emitting element (230c) are symmetrically configured, the area with weak color tone when viewing the display from one direction can be visually reinforced to correct the difference in color tone of the display perceived from the left and right sides. Therefore, the effect of improving the color viewing angle at the final product stage of the display device can be obtained.

[0108] In addition, by symmetrically arranging the first light-emitting element (230b) and the second light-emitting element (230c), the electric field formed by the difference in polarity between the light-emitting elements (230b, 230c) can be eliminated, thereby preventing the occurrence of parasitic capacitance. Furthermore, the ghosting phenomenon that may occur due to such parasitic capacitance can be improved.

[0109] FIG. 7 is a plan view showing the arrangement of wiring electrodes of a display device using a light-emitting element according to a comparative example. FIG. 8 is a plan view showing the arrangement of wiring electrodes of a display device using a light-emitting element according to a comparative example in more detail.

[0110] Referring to FIG. 7, the structure of an electrode and an electrode pad of a display device according to a comparative example for comparison with the present invention is partially illustrated.

[0111] Referring to FIGS. 7 and 8, two pixel regions (24, 25) are shown, and each pixel region may include three light sources (23a, 23b, 23c).

[0112] The light source may include a red LED (23a), a green LED (23b), and a blue LED (23c). Each LED (23a, 23b, 23c) may be electrically connected to a pair of electrode pads (24a, 24b). For example, the first electrode pad (24a) of each LED (23a, 23b, 23c) may be connected to a pixel electrode (not shown) through a via hole (26), and the second electrode pad (24b) of each LED (23a, 23b, 23c) may be connected to a common electrode (not shown) by a via hole (27).

[0113] Here, the second electrode pad (24b) connected to the three LEDs (23a, 23b, 23c) is connected to the common electrode, so it can be connected to each other by the connecting electrodes (24N, 25N).

[0114] At this time, an extension portion (21, 22) is formed in the first electrode pad (24a), and a via hole (26) can be located in the extension portion (21, 22).

[0115] As displays utilizing light-emitting elements such as LEDs advance, the demand for narrow-pitch displays (the distance between LED light sources) is increasing. Implementing narrow-pitch displays requires high-density design technology for LED light sources; consequently, PCBs forming the wiring substrates tend to be designed and implemented in multiple layers.

[0116] In such a multilayer wiring board, electrical connections between each layer can be made through via holes (26, 27). Typically, the via holes can be located overlapping with the electrode pad area where the LED light source is located (transferred). Referring to FIG. 8, a via hole (26) is located in an extension (21, 22) formed on the first electrode pad (24a).

[0117] If the via hole is spaced apart from the electrode pad at a certain distance, the shape and width of the electrode pad may not be affected by the via hole; however, as the pitch becomes narrower due to the high image quality expected as described above, there is less spatial room to position the via hole further away from the electrode pad. Consequently, the via hole may end up overlapping with the pad.

[0118] For example, while an electrode pad connected to a common electrode can be connected using a single via hole, the electrode pad connected to a pixel electrode must be connected to the RGB LEDs forming each subpixel, so the density of via holes for the common electrode and the pixel electrode may differ. For example, the density of via holes connected to the pixel electrode increases by approximately three times or more, and consequently, the probability of a situation occurring where via holes overlap with electrode pads may increase.

[0119] When vias overlap with electrodes, as illustrated in FIG. 8, the shape and area of ​​the electrode pad (24a) connected to the negative (-) electrode (scan electrode; 24N, 25N) and the electrode pad (24b) connected to the positive (+) electrode can be formed differently depending on the density of the via holes (26, 27).

[0120] Accordingly, when applying solder for the transfer (bonding) of the LEDs (23a, 23b, 23c) on the electrode pads (24a, 24b), the amount of solder may vary. Consequently, the amount of solder on both electrode pads (24a, 24b) may vary. This may cause a difference in the height of the solder. Consequently, the left and right heights of the LEDs (23a, 23b, 23c) may differ, and the LEDs (23a, 23b, 23c) may be transferred tilted to one side rather than flat. In this way, if the LEDs (23a, 23b, 23c) are transferred tilted, the direction of light emission from the light source is distorted, and the intensity of light changes depending on the viewing angle, which may result in an abnormality in image quality.

[0121] FIG. 9 is a plan view showing the arrangement of wiring electrodes of a display device using a light-emitting element according to a first embodiment of the present invention. FIG. 10 is a detailed view of part A of FIG. 9.

[0122] A plurality of unit pixel regions may be defined on a wiring board (100; see FIG. 1). A first wiring electrode (121, 122, 123) and a second wiring electrode (124) may be provided on the wiring board (100). As described above, for example, the first wiring electrode (121, 122, 123) may be a signal electrode or a data electrode. Additionally, the second wiring electrode (124) may be a common electrode or a scan electrode.

[0123] In an exemplary embodiment, an electrode pad (130, 131, 132: hereinafter, first electrode pad) arranged in one direction may be connected to a first wiring electrode (121, 122, 123; signal electrode or data electrode). Additionally, an electrode pad (140, 141, 142: hereinafter, second electrode pad) arranged in the other direction may be connected to a second wiring electrode (124; common electrode or scan electrode).

[0124] For example, the first wiring electrode (121, 122, 123) forming the signal electrode or data electrode may be a positive (+) electrode, and the second wiring electrode (124) forming the common electrode or scan electrode may be a negative (-) electrode. Accordingly, the P-electrode of the light-emitting element may be connected to the first electrode pad (130, 131, 132), and the N-electrode of the light-emitting element may be connected to the second electrode pad (140, 141, 142). However, the present invention is not limited thereto. That is, as another example, the first wiring electrode (121, 122, 123) forming the signal electrode or data electrode may be a negative (-) electrode, and the second wiring electrode (124) forming the common electrode or scan electrode may be a positive (+) electrode.

[0125] Referring to FIGS. 9 and 10, for example, a first electrode pad (130, 131, 132) connected to a first wiring electrode (121, 122, 123) and a second electrode pad (140, 141, 142) connected to a second wiring electrode (124) are shown.

[0126] Each unit pixel area (101, 102) may include a light-emitting element (210a, 220a, 230a / 210b, 220b, 230b) that forms a subpixel and is installed by being electrically connected to a first electrode pad (130, 131, 132) and a second electrode pad (140, 141, 142).

[0127] These light-emitting elements may include a first light-emitting element (210a, 220a, 230a) located in a first pixel area (101) and installed in a first arrangement, and a second light-emitting element (210b, 220b, 230b) located in a second pixel area (102) adjacent to the first pixel area (101) and installed in a second arrangement symmetrical to the first arrangement.

[0128] At this time, the second wiring electrode (124) may be placed on the same layer as the light-emitting element (210a, 220a, 230a / 210b, 220b, 230b). Therefore, via holes may not be required in the second electrode pad (140, 141, 142) connected to the second wiring electrode (124).

[0129] Here, the first arrangement and the second arrangement may be arrangements in which the positions of the electrodes of the first light-emitting element (210a, 220a, 230a) and the second light-emitting element (210b, 220b, 230b) are symmetrical to each other. As described above, the first light-emitting element (210a, 220a, 230a) and the second light-emitting element (210b, 220b, 230b) may emit light of the same color.

[0130] In an exemplary embodiment, a second wiring electrode (124) corresponding to a first pixel area (101) and an adjacent second wiring electrode (124) corresponding to a second pixel area (102) may be positioned symmetrically with respect to the center between the first pixel area (101) and the second pixel area (102).

[0131] For example, the first pixel area (101) and the second pixel area (102) can be paired between adjacent second wiring electrodes (124).

[0132] In an exemplary embodiment, the first pixel area (101) or the second pixel area (102) may be located in multiple numbers along the second wiring electrode (124).

[0133] As mentioned above, the second wiring electrode (124) may be a common electrode that is commonly connected to a plurality of first pixel areas (101) or second pixel areas (102).

[0134] In this way, by means of the first arrangement and the second arrangement, the electric field generated from the difference in electrical polarity between the first light-emitting element (210a, 220a, 230a) and the second light-emitting element (210b, 220b, 230b) can be canceled out.

[0135] In an exemplary embodiment, the first wiring electrode (121, 122, 123) may be disposed on a different layer from the light-emitting element (210a, 220a, 230a / 210b, 220b, 230b) through a via hole (260) connected to the first electrode pad (130, 131, 132). Accordingly, the first wiring electrode (121, 122, 123) is not illustrated in FIG. 9 and FIG. 10.

[0136] For example, the second electrode pad (140, 141, 142) may include a pad extension (143, 144). This pad extension (143, 144) may include a first extension (143) and a second extension (144) that extends further than the first extension (143).

[0137] In this case, for example, the via hole (260) may be located in the pad extension (143, 144) (see FIG. 10). In this way, the via hole (260) may be located in the first extension (143) and the second extension (144), respectively, which are located at different positions.

[0138] In this way, one side wiring electrode (second wiring electrode (124)) is placed on the same layer as the light-emitting element, that is, on the outermost layer, so that the number of via holes can be reduced.

[0139] Accordingly, the degree of freedom for pixel placement can be increased, and in the case of high-density pixel placement due to increased resolution, it may not be affected by via holes.

[0140] FIG. 11 is a plan view showing the arrangement of wiring electrodes of a display device using a light-emitting element according to a second embodiment of the present invention. FIG. 12 is a detailed view of part B of FIG. 11.

[0141] Referring to FIGS. 11 and 12, for example, a first electrode pad (130, 131, 132) connected to a first wiring electrode (121, 122, 123) and a second electrode pad (140, 141, 142) connected to a second wiring electrode (124) are shown.

[0142] Each unit pixel area (101, 102) may include a light-emitting element (210a, 220a, 230a / 210b, 220b, 230b) that forms a subpixel and is installed by being electrically connected to a first electrode pad (130, 131, 132) and a second electrode pad (140, 141, 142).

[0143] These light-emitting elements may include a first light-emitting element (210a, 220a, 230a) located in a first pixel area (101) and installed in a first arrangement, and a second light-emitting element (210b, 220b, 230b) located in a second pixel area (102) adjacent to the first pixel area (101) and installed in a second arrangement symmetrical to the first arrangement.

[0144] At this time, the second wiring electrode (124) may be placed on the same layer as the light-emitting element (210a, 220a, 230a / 210b, 220b, 230b). Therefore, via holes may not be required in the second electrode pad (140, 141, 142) connected to the second wiring electrode (124).

[0145] In an exemplary embodiment, the first wiring electrode (121, 122, 123) may be disposed on a different layer from the light-emitting element (210a, 220a, 230a / 210b, 220b, 230b) through a via hole (260) connected to the first electrode pad (130, 131, 132). Accordingly, the first wiring electrode (121, 122, 123) is not illustrated in FIG. 11 and FIG. 12.

[0146] Referring to FIG. 11, for example, the first electrode pad (130, 131, 132) may include a pad extension (145). A via hole (261) may be located in this pad extension (145).

[0147] These pad extensions (145) can be connected to each other for adjacent pixel regions (101, 102). In an exemplary embodiment, the pad extensions (145) can be connected to each other for pixel regions (101, 102) facing each other.

[0148] In an exemplary embodiment, for the interconnected pad extensions (145), the via hole (261) may be shared in the first pixel area (101) and the second pixel area (102).

[0149] In this way, the first electrode pad (130, 131, 132) located in the first pixel area (101) and the first electrode pad (130, 131, 132) located in the second pixel area (102) can be connected to each other by a pad extension (145). This pad extension (145) can be located at the same position in the vertical direction of the pixel areas (101, 102). In this case, the distance between adjacent pixel areas (101, 102) is limited, so the position of the via hole (261) may be limited.

[0150] Meanwhile, referring to FIG. 12, a pad extension portion (145, 146, 147) may be provided to connect the first electrode pads (130, 131, 132) of each light-emitting element (210a, 220a, 230a) to adjacent pixel regions (101, 102) at different locations.

[0151] For example, each pad extension (145, 146, 147) may be located at different positions with respect to the vertical direction of the pixel area (101, 102). Accordingly, via holes (261, 262, 263) may be located at different positions with respect to the vertical direction of the pixel area (101, 102).

[0152] Any parts not otherwise described may be identical to the description of the first embodiment described above with reference to FIGS. 9 and FIGS. 10. Therefore, redundant descriptions are omitted.

[0153] FIG. 13 is a schematic diagram showing the operation of a display device using a light-emitting element according to a second embodiment of the present invention.

[0154] Referring to FIG. 13, this is a diagram schematically illustrating the driving process in the case of having 36 scan lines (multiplexing lines) in the configuration of the second embodiment described above.

[0155] The driving of such display devices can be achieved based on the Passive Matrix (PM) driving principle.

[0156] In a display device using PM-driven light-emitting elements, a multiplexing control is used to alternately turn on / off multiple LED light sources (RED / GREEN / BLUE) for horizontal light-emitting elements (210a, 210b / 220a, 220b / 230a, 230b) line by line, and a driving method is used to output video data vertically.

[0157] The control of the PM drive method is such that, for example, in the case of a 36-line multiplexing method, the 36 horizontal rows of light-emitting elements are turned on sequentially and alternately by dividing the time (only one row is turned on at a time). When one row of light-emitting elements is turned on in a unit of time, the remaining 35 horizontal rows are turned off.

[0158] The number of vertically connected light-emitting elements in this horizontal row depends on the number of pixels of RGB data controlled by the driver IC.

[0159] In the video data output control of the PM drive method, multiple light-emitting elements are connected in a vertical row, and the same video data can be output to these multiple light-emitting elements. For example, in a 36-line multiplexing method, 36 light-emitting elements can be connected vertically together in a single vertical row. Therefore, the same data is output to the 36 light-emitting elements at the same time, and another video data is output at the next time in accordance with the difference in unit time when the horizontal lines are turned on alternately.

[0160] According to this PM driving method, horizontal lines are connected together as multiplexing lines, and vertical lines are connected together as video data lines.

[0161] The horizontal lines for multiplexing and the vertical lines for video data output control in this configuration can be applied identically even if the multiplexing is changed to the vertical lines and the video data output control to the horizontal lines.

[0162] The light-emitting element is composed of R, G, and B sub-light sources (210, 220, 230) and emits light by applying voltage to the positive electrode and negative electrode applied to R, G, and B.

[0163] Referring to Fig. 13, individual data is applied to the R, G, and B sub-light sources to match the color of the image data at the + electrode of the R, G, and B sub-light sources, and the - electrode can be connected by grouping the sub-light sources together as a common electrode.

[0164] FIG. 14 is a schematic diagram showing a specific example of a subpixel arrangement of a display device using a light-emitting element according to one embodiment of the present invention.

[0165] Referring to FIG. 14, light-emitting elements (230a, 230b, 230c, 230d) are shown installed on a wiring board (100) in a symmetrical arrangement relative to each other. This may correspond to the arrangement of light-emitting elements shown in FIG. 6 in which they are connected in parallel.

[0166] As mentioned above, the light-emitting elements (230a, 230b, 230c, 230d) may have an asymmetric light distribution (a, b) with respect to the direction connecting the first type electrode (235) and the second type electrode (237). Additionally, each light-emitting element (230a, 230b, 230c, 230d) may have an asymmetric light distribution (a, b; see FIG. 2) with respect to the direction connecting the first electrode pad (132) and the second electrode pad (142).

[0167] For example, the first light-emitting element (230a) and the third light-emitting element (230c) may have a light distribution (a) skewed to the left. This corresponds to the first arrangement. Additionally, the second light-emitting element (230b) located between the first light-emitting element (230a) and the third light-emitting element (230c), and the fourth light-emitting element (230d) located to the right of the third light-emitting element (230c), may have a light distribution (b) skewed to the right. This corresponds to the second arrangement.

[0168] This may be a result of the material properties of at least one of the substrate (231) and the semiconductor layer (232). For example, this phenomenon may occur because the crystal structure of at least one of the substrate (231) and the semiconductor layer (232) has a tilted shape.

[0169] FIG. 14 illustrates a state in which each light-emitting element (230a, 230b, 230c, 230d) has a tilted crystal structure. In particular, when considering a region (hereinafter referred to as the first region; 230) where two adjacent pixels form a pair, the first light-emitting element (230a) of one pixel and the second light-emitting element (230b) of the other pixel may have a tilt angle that is symmetrical to each other. For example, the first light-emitting element (230a) and the second light-emitting element (230b) may form an angle that is inclined in a direction away from each other. Additionally, in the second region (231) adjacent to the first region (230), the third light-emitting element (230c) and the fourth light-emitting element (230d) of the other pixel may have a tilt angle that is symmetrical to each other.

[0170] FIG. 15 is a schematic diagram showing another specific example of a subpixel arrangement of a display device using a light-emitting element according to one embodiment of the present invention.

[0171] Referring to FIG. 15, a state is illustrated in which light-emitting elements (230e, 230f, 230g, 230h) are installed on a wiring board (100) in a symmetrical arrangement relative to each other. This may correspond to a state in which the arrangement of light-emitting elements shown in FIG. 6 is connected in parallel.

[0172] As mentioned above, the light-emitting elements (230e, 230f, 230g, 230h) may have an asymmetric light distribution (a, b) with respect to the direction connecting the first type electrode (235) and the second type electrode (237). Additionally, each light-emitting element (230e, 230f, 230g, 230h) may have an asymmetric light distribution (a, b; see FIG. 2) with respect to the direction connecting the first electrode pad (132) and the second electrode pad (142).

[0173] FIG. 15 illustrates a state in which each light-emitting element (230e, 230f, 230g, 230h) has a tilted crystal structure. In particular, when considering the region where two adjacent pixels form a pair (hereinafter, the third region; 232), the fifth light-emitting element (230e) of one pixel and the sixth light-emitting element (230f) of the other pixel may have a tilt angle that is symmetrical to each other. For example, the fifth light-emitting element (230e) and the sixth light-emitting element (230f) may form an angle that is inclined toward each other. Additionally, in the fourth region (233) adjacent to the third region (232), the seventh light-emitting element (230g) and the eighth light-emitting element (230h) of the other pixel may also have a tilt angle that is symmetrical to each other.

[0174] Figure 16 is a diagram schematically showing the subpixel arrangement of Figures 14 and 15.

[0175] FIG. 16(a) schematically illustrates a state in which a pair (pari) of a first light-emitting element (230a) and a second light-emitting element (230b) in the first region (230) of FIG. 14 forms an angle inclined in a direction away from each other.

[0176] Additionally, FIG. 16(b) schematically illustrates a state in which a pair (pari) of the fifth light-emitting element (230e) and the sixth light-emitting element (230f) in the third region (232) of FIG. 15 forms an angle inclined in a direction that brings them closer to each other.

[0177] As explained above, when light-emitting elements are symmetrically positioned in pairs with neighboring pixels, the skewed light distribution (a, b) caused by the crystal structure of the light-emitting elements can be canceled out. In other words, the problem of colors appearing differently depending on the viewing direction when looking at the display device from the outside can be resolved.

[0178] FIG. 17 is a schematic diagram showing the process of forming a subpixel arrangement according to FIG. 14.

[0179] An example of a method for transferring light-emitting elements to have different arrangements as described above is briefly explained with reference to FIG. 17.

[0180] For example, light-emitting elements (230a, 230c) can be first transferred to electrode pads (#1, #3, etc.) in odd columns of a wiring board, and then, after rotating the positions of the light-emitting elements by 180 degrees, light-emitting elements (230b, 230d) can be transferred to electrode pads (#2, #4, etc.) in even columns of the wiring board.

[0181] The light-emitting elements (230a to 230d) can be transferred to a wiring substrate after being transferred to a transfer substrate (410) while positioned on a wafer (500). Here, the transfer substrate (410) may be, for example, blue tape.

[0182] First, light-emitting elements (230a, 230c) can be transferred to a transfer substrate (410) in a state of arrangement such as ① on the upper side (a state in which the reference point M of the wafer (500) is located on the left).

[0183] Next, the light-emitting elements (230a, 230c) transferred to the transfer substrate (410) can be transferred to the electrode pads (#1, #3, etc.) of the odd-numbered columns of the wiring substrate.

[0184] Afterwards, as shown in ② below, the wafer (500) is rotated 180 degrees (the reference point M of the wafer (500) is located on the right side), and the light-emitting elements (230b, 230d) can be transferred to the transfer substrate (410).

[0185] Next, the light-emitting elements (230b, 230d) transferred to the transfer substrate (410) can be transferred to the electrode pads (#2, #4, etc.) of an even column of the wiring substrate.

[0186] Through this process, light-emitting elements (230a to 230h) having the arrangement as shown in FIGS. 15 to 16 can be transferred onto a wiring substrate.

[0187] FIG. 18 is a side view showing an individual light-emitting element of a display device using a light-emitting element according to one embodiment of the present invention. FIG. 19 is a schematic diagram showing the tilt angle of an individual light-emitting element of a display device using a semiconductor light-emitting element according to one embodiment of the present invention.

[0188] FIG. 18 is an enlarged photograph showing the side of a blue light-emitting element (230). FIG. 18 may show a sapphire substrate that makes up most of the thickness of the blue light-emitting element (230). As shown in FIG. 19, the tilt angle (α) of the blue light-emitting element (230) may be approximately 10 degrees. Also, for example, the thickness (t) of the blue light-emitting element (230) may be 80 μm.

[0189] However, a gallium nitride semiconductor layer located on a sapphire substrate may also have the same or similar tilt angle. In some cases, the sapphire substrate may be removed after the light-emitting device is fabricated, in which case the gallium nitride-based semiconductor layer, rather than the substrate, may have the tilt angle as described above.

[0190] FIG. 20 schematically illustrates the crystal planes and crystal orientations of sapphire. Sapphire can be used as a growth substrate for light-emitting devices made of gallium nitride-based semiconductors.

[0191] As illustrated, sapphire has tilted crystal planes. For example, the R-plane has a crystal plane tilted toward the m-axis. Typically, sapphire can have an R-plane as a growth plane. Referring to FIG. 20, since the R-plane has a plane tilted relative to the hexagonal prism crystal shape, the sapphire substrate and the gallium nitride-based semiconductor grown on the crystal plane of the sapphire substrate can have such a tilted angle.

[0192] In addition, such a tilt angle can also be formed due to the cutting of the sapphire substrate in the direction of the crystal plane after the light-emitting element is formed with a gallium nitride-based semiconductor on the sapphire substrate.

[0193] FIG. 21 is a side view showing light-emitting elements of a display device using a light-emitting element according to an embodiment of the present invention. FIG. 22 is a schematic diagram showing the tilt angle of light-emitting elements of a display device using a semiconductor light-emitting element according to an embodiment of the present invention.

[0194] Referring to FIGS. 21 and 22, light-emitting elements that can be used in a display may have various tilt angles. For example, the light-emitting elements shown in FIGS. 21(A) and FIGS. 22(A) may have a tilt angle of 5 degrees or less in one direction.

[0195] In addition, the light-emitting element illustrated in FIGS. 21(B) and FIGS. 22(B) may have a tilt angle of 12 degrees or less in the opposite direction to the tilt angle of the light-emitting element illustrated in FIGS. 21(A) and FIGS. 22(A).

[0196] In addition, the light-emitting element shown in FIGS. 21(C) and FIGS. 22(C) may have a tilt angle of 10 degrees or less in the same direction as the tilt angle of the light-emitting element shown in FIGS. 21(B) and FIGS. 22(B).

[0197] In this way, the light-emitting element has a parallelogram structure in which the side cross-section is tilted to one side, and as explained above, the light-emitting direction can have an uneven and skewed light-emitting pattern with respect to the direction perpendicular to the surface.

[0198] The above description is merely an illustrative explanation of the technical concept of the present invention, and those skilled in the art to which the present invention pertains will be able to make various modifications and variations within the scope of the essential characteristics of the present invention.

[0199] Accordingly, the embodiments disclosed in this invention are intended to explain, not limit, the technical concept of the invention, and the scope of the technical concept of the invention is not limited by these embodiments.

[0200] The scope of protection of the present invention shall be interpreted by the claims below, and all technical ideas within an equivalent scope shall be interpreted as being included within the scope of rights of the present invention. Explanation of the symbols

[0201] 100: Wiring board 101, 102: Pixel area 110: Substrate 121, 122, 123, 124: Wiring electrodes 130, 140 / 131, 141 / 132, 142: Electrode pads 143, 144, 145, 146, 147: Pad extension 200, 210, 220, 230: Light-emitting elements 260, 261, 262, 263: Via Hole

Claims

Claim 1 A wiring board having a plurality of defined unit pixel regions; a first wiring electrode which is a signal electrode and a second wiring electrode which is a common electrode arranged on the wiring board; a first electrode pad and a second electrode pad which are respectively connected to the first wiring electrode and the second wiring electrode; and a light-emitting element which is installed to be electrically connected to the first electrode pad and the second electrode pad in each of the unit pixel regions to form a subpixel, wherein the light-emitting element comprises a first light-emitting element located in a first pixel region and installed in a first arrangement; A display device using a light-emitting element, comprising: a second light-emitting element located in a second pixel area adjacent to the first pixel area and installed in a second arrangement symmetrical to the first arrangement; wherein the second wiring electrode is arranged on the same layer as the light-emitting element, and the first wiring electrode is arranged on a different layer from the light-emitting element so as to be connected to the first electrode pad through a via hole; wherein the first electrode pad includes a pad extension portion where the via hole is located, and the pad extension portion is connected between a first pixel area and a second pixel area facing each other so that the via hole is shared between the first pixel area and the second pixel area, wherein a first separation distance between one subpixel in the first pixel area and the corresponding via hole and a second separation distance between another subpixel in the first pixel area and the corresponding via hole are different from each other, and the direction of the first separation distance and the direction of the second separation distance are parallel to each other. Claim 2 delete Claim 3 delete Claim 4 delete Claim 5 delete Claim 6 delete Claim 7 delete Claim 8 delete Claim 9 A display device using a light-emitting element according to claim 1, wherein the first arrangement and the second arrangement are arrangements in which the positions of the electrodes of the first light-emitting element and the second light-emitting element are symmetrical to each other. Claim 10 A display device using a light-emitting element according to claim 1, wherein a second wiring electrode corresponding to the first pixel area and an adjacent second wiring electrode corresponding to the second pixel area are positioned symmetrically with respect to the center between the first pixel area and the second pixel area. Claim 11 A display device using a light-emitting element according to claim 1, wherein the first pixel region and the second pixel region form a pair between adjacent second wiring electrodes. Claim 12 A display device using a light-emitting element according to claim 1, wherein the first light-emitting element and the second light-emitting element emit light of the same color. Claim 13 A display device using a light-emitting element, characterized in that, in claim 1, the first pixel area is positioned in multiple locations along the second wiring electrode. Claim 14 A display device using a light-emitting element, characterized in that, in claim 13, the second wiring electrode is commonly connected to a plurality of first pixel regions. Claim 15 A display device using a light-emitting element, characterized in that, in claim 1, the electric field generated from the difference in electrical polarity between the first light-emitting element and the second light-emitting element is canceled out by the first arrangement and the second arrangement.

Images