LED display module and method for manufacturing LED display module

Abstract

The present invention relates to an LED display module and a method for manufacturing the LED display module. The LED display module comprises: a circuit board; a plurality of LED chips mounted on one side surface of the circuit board; an LED chip protection unit which surrounds and covers the plurality of LED chips such that the plurality of LED chips are sealed, and which is stacked on the circuit board; and a static electricity discharge unit which includes a conductive pattern having a planar shape that does not cover the plurality of LED chips and made of a conductive material, and which is stacked on the LED chip protection unit.

Description

LED display module and LED display module manufacturing method

[0001] The present invention relates to an LED display module included in an LED display device, and a method for manufacturing an LED display module.

[0002] An LED display device is a display device that uses LED chips containing light-emitting diodes (LEDs) as pixels, and includes an LED display module in which a plurality of LED chips are arranged in a matrix. An LED display device with a large screen may include a plurality of LED display modules.

[0003] Since LED display modules have a structure in which multiple LED chips are exposed toward the screen, they may be vulnerable to high-voltage shocks from the outside, such as electrostatic discharge (ESD).

[0004] The background technology of the present invention is disclosed in Korean Patent Publication No. 10-2019-0129107 (published on November 19, 2019, title of the invention: LED device having one or more communication units and method using the same).

[0005] The present invention was created to improve the above-mentioned problems, and the purpose of the present invention is to provide an LED display module and a method for manufacturing an LED display module in which the LED chip is not damaged by an external high-voltage shock.

[0006] An LED display module according to the present invention comprises: a circuit board; a plurality of LED chips mounted on one side of the circuit board; an LED chip protection member laminated on the circuit board, surrounding and covering a plurality of LED chips so as to seal the plurality of LED chips; and a static electricity discharge member having a flat shape that does not cover the plurality of LED chips and including a conductive pattern made of a conductive material, the static electricity discharge member being laminated on the LED chip protection member.

[0007] The above electrostatic discharge unit may further include a resin base that includes a transparent resin and supports the conductive pattern and is supported by the LED chip protection unit.

[0008] The above-mentioned challenging pattern may include a plurality of intersecting first micro-lines and a plurality of second micro-lines.

[0009] The width of the first fine line portion and the width of the second fine line portion may be smaller than the gap between a pair of adjacent LED chips among the plurality of LED chips.

[0010] The conductive material may include a glossy metal, and the conductive pattern may further include an opaque printing layer covering the plurality of first fine lines and the plurality of second fine lines so that the plurality of first fine lines and the plurality of second fine lines are not visible.

[0011] The above-mentioned conductive material may include at least one of copper (Cu), silver (Ag), gold (Au), and ITO (Indium Tin Oxide).

[0012] The LED display module may further include a ground terminal mounted on the other side of the circuit board; and an internal connection portion for electrically connecting the conductive pattern and the ground terminal without covering the plurality of LED chips.

[0013] The connecting portion within the above module may include a metal layer that is electrically conductive and is provided on the outer periphery of the circuit board.

[0014] The connecting portion within the module may further include an opaque printed layer covering the metal layer so that the metal layer is not visible.

[0015] The connection portion within the module may include a via hole that includes a conductive metal and extends to penetrate the circuit board in the thickness direction.

[0016] The LED display module is provided in a plurality of units, and a pair of LED display modules among the plurality of LED display modules are arranged adjacently, and the LED display module may further include an inter-module connection part that is electrically connected to the conductive pattern of the adjacent LED display module.

[0017] A method for manufacturing an LED display module according to the present invention comprises: an LED chip mounting step of mounting a plurality of LED chips on one side of a circuit board; an LED chip protection part forming step of forming an LED chip protection part laminated on the circuit board to surround and cover a plurality of LED chips so that the plurality of LED chips are sealed; and an electrostatic discharge part laminating step of laminating an electrostatic discharge part having a flat shape that does not cover the plurality of LED chips and including a conductive pattern made of a conductive material on the LED chip protection part.

[0018] The above electrostatic discharge unit is formed of a transparent resin and further includes a resin base that supports the conductive pattern, and the electrostatic discharge unit laminating step may include a step of bonding the resin base to the LED chip protection unit using an adhesive.

[0019] In an LED display module according to the present invention, an LED chip protection unit including a resin material physically protects a plurality of LED chips, and a static electricity discharge unit spaced apart from the plurality of LED chips discharges high voltage such as static electricity to the outside so as not to induce high voltage such as static electricity into the inside.

[0020] Therefore, multiple LED chips and circuit boards can be physically and electrically protected, enhancing durability. Furthermore, the electrostatic discharge section can shield external EMI, further enhancing durability.

[0021] FIG. 1 is a cross-sectional view of an LED display module according to a first embodiment of the present invention.

[0022] Figure 2 is an enlarged cross-sectional view of part II of Figure 1.

[0023] Figure 3 is a plan view of Figure 2 viewed from above.

[0024] FIG. 4 is an enlarged cross-sectional view of a portion of an LED display module corresponding to portion A of FIG. 1, and is a drawing illustrating one embodiment of a module connection part included in the LED display module.

[0025] FIG. 5 is an enlarged cross-sectional view of a portion of an LED display module corresponding to portion A of FIG. 1, and is a drawing illustrating another embodiment of a module connection part included in the LED display module.

[0026] FIG. 6 is an enlarged cross-sectional view of a portion of an LED display module corresponding to portion A of FIG. 1, and is a drawing illustrating one embodiment of a module-to-module connection included in the LED display module.

[0027] Fig. 7 is an enlarged cross-sectional view of a portion of an LED display module corresponding to portion A of Fig. 1, and is a drawing illustrating another embodiment of a module-to-module connection included in the LED display module.

[0028] FIG. 8 is a block diagram showing a method for manufacturing an LED display module according to a first embodiment of the present invention.

[0029] FIG. 9 is an exploded cross-sectional view of an LED display module for explaining a method for manufacturing an LED display module according to a first embodiment of the present invention.

[0030] Fig. 10 is a cross-sectional view of an LED display module according to a second embodiment of the present invention.

[0031] Fig. 11 is an enlarged cross-sectional view of part XI of Fig. 10.

[0032] Figure 12 is a plan view of Figure 11 viewed from above.

[0033] FIG. 13 is an enlarged cross-sectional view of a portion of an LED display module corresponding to portion B of FIG. 10, and is a drawing illustrating one embodiment of a module connection part included in the LED display module.

[0034] Fig. 14 is an enlarged cross-sectional view of a portion of an LED display module corresponding to part B of Fig. 10, and is a drawing showing another embodiment of a module-internal connection included in the LED display module.

[0035] FIG. 15 is an enlarged cross-sectional view of a portion of an LED display module corresponding to portion B of FIG. 10, and is a drawing illustrating one embodiment of a module-to-module connection included in the LED display module.

[0036] Fig. 16 is an enlarged cross-sectional view of a portion of an LED display module corresponding to part B of Fig. 10, and is a drawing showing another embodiment of a module-to-module connection included in the LED display module.

[0037] FIG. 17 is a block diagram showing a method for manufacturing an LED display module according to a second embodiment of the present invention.

[0038] Fig. 18 is an exploded cross-sectional view of an LED display module for explaining a method for manufacturing an LED display module according to a second embodiment of the present invention.

[0039] Hereinafter, with reference to the attached drawings, an LED display module and a method for manufacturing an LED display module according to an embodiment of the present invention will be described in detail. The terminology used in this specification is intended to appropriately express preferred embodiments of the present invention and may vary depending on the intent of the user or operator or the customary practices in the field to which the present invention pertains. Therefore, the definitions of these terms should be based on the contents throughout this specification.

[0040] FIG. 1 is a cross-sectional view of an LED display module according to a first embodiment of the present invention, FIG. 2 is an enlarged cross-sectional view of part II of FIG. 1, FIG. 3 is a plan view of FIG. 2 as viewed from above, FIG. 4 is an enlarged cross-sectional view of a part of an LED display module corresponding to part A of FIG. 1, and is a drawing illustrating an embodiment of a module-to-module connection included in the LED display module, FIG. 5 is an enlarged cross-sectional view of a part of an LED display module corresponding to part A of FIG. 1, and is a drawing illustrating another embodiment of a module-to-module connection included in the LED display module, FIG. 6 is an enlarged cross-sectional view of a part of an LED display module corresponding to part A of FIG. 1, and is a drawing illustrating an embodiment of a module-to-module connection included in the LED display module, FIG. 7 is an enlarged cross-sectional view of a part of an LED display module corresponding to part A of FIG. 1, and is a drawing illustrating another embodiment of a module-to-module connection included in the LED display module, and FIG. 8 is a block diagram showing a method for manufacturing an LED display module according to the first embodiment of the present invention. is a diagram, and FIG. 9 is an exploded cross-sectional view of an LED display module for explaining a method of manufacturing an LED display module according to a first embodiment of the present invention.

[0041] Referring to FIGS. 1 to 3 and 9, an LED display module (100) according to a first embodiment of the present invention is included in an LED display device and includes a circuit board (110), a plurality of LED chips (120), an LED chip protection unit (125), and a static electricity discharge unit (130). The LED display module (100) may have a rectangular planar shape.

[0042] A plurality of LED chips (120) may be mounted on one side of a circuit board (110). The plurality of LED chips (120) may be arranged to form a matrix. The plurality of LED chips (120) may correspond one-to-one with a plurality of pixels constituting a screen.

[0043] Each LED chip (120) is configured to emit all natural colors by packaging multiple LEDs that emit light of different colors into one, for example, one LED that emits R (red) color light, one LED that emits G (green) color light, and one LED that emits B (blue) color light into one.

[0044] The circuit board (110) is bendable. Therefore, the LED display module (100) can be applied not only to a display device having a flat, flat screen, but also to a display device having a curved screen.

[0045] The LED display module (100) may further include a power connector (113) and a signal connector (117) installed on the other side of the circuit board (110), that is, on the opposite side to the side on which the plurality of LED chips (120) are mounted. The power connector (113) may be a connector connected to a power line (not shown) so that electric energy is supplied to the plurality of LED chips (120) and the circuit board (110), and the signal connector (117) may be a connector connected to a signal line so that a video signal corresponding to an image displayed on the screen is supplied to the plurality of LED chips (120).

[0046] The LED display module (100) may further include a ground terminal (115) mounted on the other side of the circuit board (110). The ground terminal (115) may be electrically connected to a ground line (not shown) so that high voltage, such as electrostatic discharge (ESD) generated in the LED display module (100) or introduced from the outside to the inside of the LED display module (100), is discharged to the outside of the LED display module (100).

[0047] The LED chip protection member (125) surrounds and covers the plurality of LED chips (120) so that the plurality of LED chips (120) are sealed, and is laminated on the circuit board (110). The LED chip protection member (125) may be formed of, for example, a transparent resin such as epoxy. The transparent resin may be applied to one side of the circuit board (110) on which the plurality of LED chips (120) are mounted, and the LED chip protection member (125) may be laminated by curing the transparent resin.

[0048] The material of the LED chip protection member (125) may include a room temperature curing resin that cures at room temperature, or an ultraviolet curing resin that cures by ultraviolet (UV) irradiation. The material of the LED chip protection member (125) may be an insulating material.

[0049] A plurality of LED chips (120) can be physically protected by the LED chip protection unit (125). For example, the LED chip protection unit (125) can have waterproof, moisture-proof, heat-dissipating, and buffering properties to protect the plurality of LED chips (120).

[0050] The electrostatic discharge unit (130) has a planar shape that does not cover the plurality of LED chips (120) and includes a conductive pattern (133) made of a conductive material. The conductive pattern (133) may include a plurality of first fine line portions (134) that extend through and between adjacent pairs of rows of the plurality of LED chips (120) that form a matrix in the planar shape of the LED display module (100), and a plurality of second fine line portions (135) that extend through and between adjacent pairs of columns of the plurality of LED chips (120) that form a matrix in the planar shape of the LED display module (100).

[0051] The plurality of first fine lines (134) are parallel to each other, the plurality of second fine lines (135) are parallel to each other, and the plurality of first fine lines (134) and the plurality of second fine lines (135) can intersect. For example, the first fine lines (134) and the second fine lines (135) can be orthogonal. When the plurality of first fine lines (134) and the plurality of second fine lines (135) are orthogonal, the conductive pattern (133) can be formed in a grid pattern.

[0052] The size of the width (WD1) of the first fine line portion (134) may be smaller than the size of the spacing (GP1) between adjacent pairs of LED chips (120). For example, the size of the width (WD1) of the first fine line portion (134) may be smaller than the size of the spacing (GP1) between adjacent pairs of rows of a plurality of LED chips (120) forming a matrix.

[0053] The size of the width (WD2) of the second fine line portion (135) may be smaller than the size of the gap (GP2) between a pair of adjacent LED chips (120). For example, the size of the width (WD2) of the second fine line portion (135) may be smaller than the size of the gap (GP2) between a pair of adjacent columns of a plurality of LED chips (120) forming a matrix.

[0054] With this configuration, the first fine line portion (134) and the second fine line portion (135) do not overlap with the LED chip (120) in the thickness direction of the LED display module (100), and the plurality of LED chips (120) may not be covered by the plurality of first fine line portions (134) and the plurality of second fine line portions (135).

[0055] The conductive material of the conductive pattern (133) may include at least one of copper (Cu), silver (Ag), gold (Au), and transparent ITO (Indium Tin Oxide). For example, the material of the first fine line portion (134) and the second fine line portion (135) may include at least one of copper (Cu), silver (Ag), gold (Au), and transparent ITO (Indium Tin Oxide).

[0056] The conductive pattern (133) may further include an opaque printing layer (137). When the material of the first fine line portion (134) and the second fine line portion (135) includes a glossy metal such as copper, silver, or gold, the first fine line portion (134) or the second fine line portion (135) may be exposed by the gloss appearing on the screen when no image is displayed on the screen of the LED display device.

[0057] The opaque printing layer (137) covers the plurality of first fine line portions (134) and the plurality of second fine line portions (135) so that the plurality of first fine line portions (134) and the plurality of second fine line portions (135) are not visible due to gloss. The opaque printing layer (137) can be laminated by printing an opaque paint, such as black, on the plurality of first fine line portions (134) and the plurality of second fine line portions (135).

[0058] The electrostatic discharge unit (130) may further include a resin base (131). The resin base (131) is formed of a transparent resin. The resin base (131) supports the conductive pattern (133) and is supported on the upper surface of the LED chip protection unit (125). The material of the resin base (131) may include, for example, transparent PET (polyethylene terephthalate).

[0059] A plurality of first fine line portions (134) and a plurality of second fine line portions (135) may be laminated on one side of a resin base (131) by a printing method. Alternatively, a conductive material may be laminated on one side of a resin base (131), and the laminated conductive material may be partially etched and removed to correspond to the pattern shape of the plurality of first fine line portions (134) and the plurality of second fine line portions (135), thereby forming a plurality of first fine line portions (134) and a plurality of second fine line portions (135).

[0060] The electrostatic discharge unit (130) is laminated on the LED chip protection unit (125). For example, a resin base (131) may be bonded to the upper surface of the LED chip protection unit (125) using an adhesive (not shown) so that the electrostatic discharge unit (130) may be laminated and combined with the LED chip protection unit (125). The conductive pattern (133) may be positioned to be spaced apart from a plurality of LED chips (120) by the LED chip protection unit (125) and the resin base (131).

[0061] The LED display module (100) may further include a transparent conductive pattern protection member (140). The conductive pattern protection member (140) may be laminated on a resin base (131) to surround and cover the conductive pattern (133) so that the conductive pattern (133) is sealed. The material of the conductive pattern protection member (140) may include a room temperature curing resin that is cured at room temperature, or an ultraviolet curing resin that is cured by ultraviolet (UV) irradiation.

[0062] The conductive pattern (133) can be physically protected by the conductive pattern protection member (140). For example, the conductive pattern protection member (140) can have waterproof, moisture-proof, heat-dissipating, and buffering properties to protect the conductive pattern (133).

[0063] Although not shown in FIGS. 1 to 3, the LED display module (100) may further include a transparent ITO layer laminated on the conductive pattern protection member (140). The material of the ITO layer may include transparent ITO, which is a transparent conductive material. The ITO layer may be laminated on the conductive pattern protection member (140) in the form of a flat film or a grid pattern. The ITO layer provides additional electrostatic capacity in addition to the conductive pattern (133), thereby helping to smoothly discharge high-voltage static electricity that is introduced to the LED display module (100) without damage.

[0064] Referring to FIG. 4, the LED display module (100) may further include an intra-module connection (150) that does not cover a plurality of LED chips (120) and electrically connects a conductive pattern (133) and a ground terminal (115).

[0065] The module-side connection portion (150) may include a corner-side connection portion (151) and a board-side connection portion (155). The board-side connection portion (155) is provided on the outer peripheral portion of the side of the circuit board (110) where the ground terminal (115) is mounted, and may be electrically connected to the ground terminal (115). The corner-side connection portion (151) is provided at a corner of the LED display module (100). One end of the corner-side connection portion (151) may be electrically connected to the conductive pattern (133), and the other end may be electrically connected to the board-side connection portion (155).

[0066] The corner-side connecting portion (151) and the substrate-side connecting portion (155) may each include a metal layer (152, 156) and an opaque printing layer (153, 157). The material of the metal layers (152, 156) may include a conductive and glossy metal.

[0067] The opaque printing layer (153, 157) can cover the metal layer (152, 156) so that the metal layer (152, 156) is not exposed due to gloss. The opaque printing layer (153, 157) can be laminated by printing an opaque paint, such as black, on the metal layer (152, 156).

[0068] One end of the metal layer (152) of the corner-side connecting portion (151) can be electrically connected to the first fine line portion (134) or the second fine line portion (135) of the conductive pattern (133). One end of the metal layer (156) of the board-side connecting portion (155) can be electrically connected to the ground terminal (115), and the other end of the metal layer (156) of the board-side connecting portion (155) can be electrically connected to the other end of the metal layer (152) of the corner-side connecting portion (151). A through hole (114) penetrating the power connector (113) can be formed in the power connector (113) so that the metal layer (156) extends to the ground terminal (115).

[0069] The metal layer (156) of the substrate-side connection portion (155) can be prepared by laminating a metal layer on the surface of the circuit board (110) or by removing the PSR (photo solder resist) laminated on the outer periphery of the circuit board (110) from among the PSR laminated on the surface of the circuit board (110) to partially expose the metal layer of the circuit board (110).

[0070] FIG. 5 illustrates another example of an intra-module connection (160) that may be included in an LED display module (100) in place of the intra-module connection (150) illustrated in FIG. 4. Referring to FIG. 5, the intra-module connection (160) may include a corner-side connection (161), a substrate-side connection (164), a via-hole connection terminal (165), and a via-hole (167).

[0071] The substrate-side connecting portion (164) may be formed to extend along a path that avoids the plurality of LED chips (120) on the side where the plurality of LED chips (120) are mounted on the circuit board (110). The corner-side connecting portion (161) is provided at the corner of the LED display module (100). One end of the corner-side connecting portion (161) may be electrically connected to the conductive pattern (133), and the other end may be electrically connected to the substrate-side connecting portion (164).

[0072] The corner-side connecting portion (161) and the substrate-side connecting portion (164) may include a metal layer and an opaque printing layer, similar to the corner-side connecting portion (151) and the substrate-side connecting portion (155) illustrated in FIG. 4.

[0073] The via hole (167) includes a conductive metal and extends to penetrate the circuit board (110) in the thickness direction. One end of the via hole (167) can be conductively connected to a ground terminal (115). The via hole connection terminal (165) is provided at an end of the board-side connection portion (164) and can be conductively connected to the other end of the via hole (167).

[0074] Referring to FIG. 6, the LED display device may include a plurality of LED display modules (100, 102) having a rectangular planar shape. The plurality of LED display modules (100, 102) may be arranged adjacently in a matrix to form a large screen. Among the plurality of LED display modules (100, 102), a pair of adjacent LED display modules (100, 102) may each include an inter-module connection portion (170) that is electrically connected to a conductive pattern (133) of the adjacent LED display module (100, 102).

[0075] The inter-module connection (170) may include an inter-module terminal (171) and a corner connection (174). The corner connection (174) may be provided at a corner of the LED display module (100). One end of the corner connection (174) may be electrically connected to the conductive pattern (133).

[0076] An inter-module terminal (171) may be provided at a corner side of the circuit board (110). The inter-module terminal (171) may be electrically connected to the other end of the corner-side connecting portion (174). When a pair of LED display modules (100, 102) are arranged adjacent to each other, the inter-module terminal (171) of one LED display module (100) and the inter-module terminal (171) of the other LED display module (102) may be electrically connected by making contact.

[0077] Accordingly, when static electricity is introduced into one LED display module (100) included in the LED display device, the static electricity is dispersed to all LED display modules (100, 102) included in the LED display device and can be discharged to the outside through the ground electrode (115).

[0078]

[0079] *Figure 7 illustrates another example of an inter-module connection (180) that may be included in an LED display module (100) in place of the inter-module connection (170) illustrated in Figure 6. Referring to Figure 7, the inter-module connection (180) may include an inter-module terminal (181) that is electrically connected to a conductive pattern (133). The inter-module terminal (181) may be provided on the outer periphery of the static electricity discharge unit (130).

[0080] When a pair of LED display modules (100, 102) are placed adjacent to each other, the inter-module terminal (181) of one LED display module (100) and the inter-module terminal (181) of the other LED display module (102) can be connected to each other so as to be electrically conductive.

[0081] Accordingly, when static electricity is introduced into one LED display module (100) included in the LED display device, the static electricity is dispersed to all LED display modules (100, 102) included in the LED display device and can be discharged to the outside through the ground electrode (115).

[0082] Referring to FIGS. 1, 8, and 9, a method for manufacturing an LED display module (100) according to a first embodiment of the present invention includes an LED chip mounting step (S110), an LED chip protection part forming step (S120), an electrostatic discharge part laminating step (S130), and a conductive pattern protection part forming step (S140).

[0083] The LED chip mounting step (S110) is a step of mounting a plurality of LED chips (120) on one side of a circuit board (110). The LED chip mounting step (S110) can be performed using surface mount technology (SMT).

[0084] The LED chip protection part forming step (S120) is a step of forming an LED chip protection part (125) that surrounds and covers a plurality of LED chips (120) so that the plurality of LED chips (120) are sealed and laminated on the circuit board (110). For example, a transparent resin such as epoxy can be applied to one side of the circuit board (110) on which the plurality of LED chips (120) are mounted and cured to form the LED chip protection part (125).

[0085] If the material of the LED chip protection part (125) is a room temperature curable resin, the LED chip protection part (125) can be left at room temperature to be cured. On the other hand, if the material of the LED chip protection part (125) is an ultraviolet (UV) curable resin, the LED chip protection part (125) can be irradiated with ultraviolet rays to be cured.

[0086] The electrostatic discharge unit laminating step (S130) is a step of laminating the electrostatic discharge unit (130) including the conductive pattern (133) on the LED chip protection unit (125). The electrostatic discharge unit (130) may further include a resin base (131). The electrostatic discharge unit laminating step (S130) may include a step of bonding the resin base (131) to the LED chip protection unit (125) using an adhesive. Since the method for manufacturing the electrostatic discharge unit (130) has been described in the description of the LED display module (100) according to the first embodiment of the present invention, any duplicate description will be omitted.

[0087] The conductive pattern protection portion forming step (S140) is a step of forming a conductive pattern protection portion (140) that surrounds and covers the conductive pattern (133) so that the conductive pattern (133) is sealed, and is laminated on the static electricity discharge portion (130).

[0088] If the material of the conductive pattern protection portion (140) is a transparent room temperature curing resin, the transparent room temperature curing resin can be applied to the resin base (131) and cured by leaving it at room temperature. If the material of the conductive pattern protection portion (140) is a transparent ultraviolet (UV) curing resin, the transparent room temperature curing resin can be applied to the resin base (131) and cured by irradiating it with ultraviolet rays.

[0089] FIG. 10 is a cross-sectional view of an LED display module according to a second embodiment of the present invention, FIG. 11 is an enlarged cross-sectional view of part XI of FIG. 10, FIG. 12 is a plan view of FIG. 11 as viewed from above, FIG. 13 is an enlarged cross-sectional view of a part of an LED display module corresponding to part B of FIG. 10, and is a drawing showing an embodiment of a module-to-module connection included in the LED display module, FIG. 14 is an enlarged cross-sectional view of a part of an LED display module corresponding to part B of FIG. 10, and is a drawing showing another embodiment of a module-to-module connection included in the LED display module, FIG. 15 is an enlarged cross-sectional view of a part of an LED display module corresponding to part B of FIG. 10, and is a drawing showing an embodiment of a module-to-module connection included in the LED display module, FIG. 16 is an enlarged cross-sectional view of a part of an LED display module corresponding to part B of FIG. 10, and is a drawing showing another embodiment of a module-to-module connection included in the LED display module, and FIG. 17 is a cross-sectional view of a part of an LED display module corresponding to part B of FIG. 10, and is a drawing showing another embodiment of a module-to-module connection included in the LED display module, and FIG. This is a block diagram showing a method for manufacturing an LED display module according to a second embodiment, and FIG. 18 is an exploded cross-sectional view of an LED display module for explaining a method for manufacturing an LED display module according to a second embodiment of the present invention.

[0090] Referring to FIGS. 10 to 12 and 18, an LED display module (200) according to a second embodiment of the present invention is included in an LED display device and includes a circuit board (210), a plurality of LED chips (220), an LED chip protection unit (225), and a static electricity discharge unit (230). The LED display module (200) may have a rectangular planar shape.

[0091] A plurality of LED chips (220) may be mounted on one side of a circuit board (210). The plurality of LED chips (220) may be arranged to form a matrix. The plurality of LED chips (220) may correspond one-to-one with a plurality of pixels constituting a screen.

[0092] Each LED chip (220) is configured to package multiple LEDs that emit light of different colors into one, for example, one LED that emits R (red) color light, one LED that emits G (green) color light, and one LED that emits B (blue) color light into one, thereby emitting all natural colors.

[0093] The circuit board (210) is bendable. Therefore, the LED display module (200) can be applied not only to a display device having a flat, flat screen, but also to a display device having a curved screen.

[0094] The LED display module (200) may further include a power connector (213) and a signal connector (217) installed on the other side of the circuit board (210), that is, on the opposite side to the side on which the plurality of LED chips (220) are mounted. The power connector (213) may be a connector connected to a power line (not shown) so that electric energy is supplied to the plurality of LED chips (220) and the circuit board (210), and the signal connector (217) may be a connector connected to a signal line so that a video signal corresponding to an image displayed on the screen is supplied to the plurality of LED chips (220).

[0095] The LED display module (200) may further include a ground terminal (215) mounted on the other side of the circuit board (210). The ground terminal (215) may be electrically connected to a ground line (not shown) so that high voltage, such as electrostatic discharge (ESD) generated in the LED display module (200) or introduced from the outside to the inside of the LED display module (200), is discharged to the outside of the LED display module (200).

[0096] The LED chip protection member (225) surrounds and covers the plurality of LED chips (220) so that the plurality of LED chips (220) are sealed, and is laminated on the circuit board (210). The LED chip protection member (225) may be formed of, for example, a transparent resin such as epoxy. The transparent resin may be applied to one side of the circuit board (210) on which the plurality of LED chips (220) are mounted, and the LED chip protection member (225) may be laminated by curing the transparent resin.

[0097] The material of the LED chip protection member (225) may include a room temperature curing resin that cures at room temperature, or an ultraviolet curing resin that cures by ultraviolet (UV) irradiation. The material of the LED chip protection member (225) may be an insulating material.

[0098] A plurality of LED chips (220) can be physically protected by the LED chip protection unit (225). For example, the LED chip protection unit (225) can have waterproof, moisture-proof, heat-dissipating, and buffering properties to protect the plurality of LED chips (220).

[0099] The electrostatic discharge unit (230) has a flat shape that does not cover a plurality of LED chips (220) and includes a conductive pattern (233) made of a conductive material. The conductive pattern (233) is immersed in the LED chip protection unit (225).

[0100] The conductive pattern (233) may include a plurality of first fine lines (234) extending through a pair of adjacent rows of a plurality of LED chips (220) forming a matrix in a planar shape of the LED display module (200), and a plurality of second fine lines (235) extending through a pair of adjacent columns of a plurality of LED chips (220) forming a matrix in a planar shape of the LED display module (200).

[0101] The plurality of first fine lines (234) are parallel to each other, the plurality of second fine lines (235) are parallel to each other, and the plurality of first fine lines (234) and the plurality of second fine lines (235) can intersect. For example, the first fine lines (234) and the second fine lines (235) can be orthogonal. When the plurality of first fine lines (234) and the plurality of second fine lines (235) are orthogonal, the conductive pattern (233) can be formed in a grid pattern.

[0102] The size of the width (WD1) of the first fine line portion (234) may be smaller than the size of the spacing (GP1) between adjacent pairs of LED chips (220). For example, the size of the width (WD1) of the first fine line portion (234) may be smaller than the size of the spacing (GP1) between adjacent pairs of rows of a plurality of LED chips (220) forming a matrix.

[0103] The size of the width (WD2) of the second fine line portion (235) may be smaller than the size of the gap (GP2) between a pair of adjacent LED chips (220). For example, the size of the width (WD2) of the second fine line portion (235) may be smaller than the size of the gap (GP2) between a pair of adjacent columns of a plurality of LED chips (220) forming a matrix.

[0104] With this configuration, the first fine line portion (234) and the second fine line portion (235) do not overlap with the LED chip (220) in the thickness direction of the LED display module (200), and the plurality of LED chips (220) may not be covered by the plurality of first fine line portions (234) and the plurality of second fine line portions (235).

[0105] The conductive material of the conductive pattern (233) may include at least one of copper (Cu), silver (Ag), gold (Au), and transparent ITO (Indium Tin Oxide). For example, the material of the first fine line portion (234) and the second fine line portion (235) may include at least one of copper (Cu), silver (Ag), gold (Au), and transparent ITO (Indium Tin Oxide).

[0106] The conductive pattern (233) may further include an opaque printing layer (237). When the material of the first fine line portion (234) and the second fine line portion (235) includes a glossy metal such as copper, silver, or gold, the first fine line portion (234) or the second fine line portion (235) may be exposed by the gloss appearing on the screen when no image is displayed on the screen of the LED display device.

[0107] The opaque printing layer (237) covers the plurality of first fine line portions (234) and the plurality of second fine line portions (235) so that the plurality of first fine line portions (234) and the plurality of second fine line portions (235) are not visible due to gloss. The opaque printing layer (237) can be formed by laminating an opaque paint, such as black, on the plurality of first fine line portions (234) and the plurality of second fine line portions (235).

[0108] The electrostatic discharge unit (230) may further include a resin base (231). The resin base (231) is formed of a transparent resin. The resin base (231) supports the conductive pattern (233). The material of the resin base (231) may include, for example, transparent PET (polyethylene terephthalate).

[0109] A plurality of first fine line portions (234) and a plurality of second fine line portions (235) may be laminated on one side of a resin base (231) by a printing method. Alternatively, a conductive material may be laminated on one side of a resin base (231), and the laminated conductive material may be partially etched and removed to correspond to the pattern shape of the plurality of first fine line portions (234) and the plurality of second fine line portions (235), thereby forming a plurality of first fine line portions (234) and a plurality of second fine line portions (235).

[0110] At least a portion of the resin base (231) may be fused to the LED chip protection portion (225) so that the conductive pattern (233) may be immersed in the LED chip protection portion (225). For example, if the static electricity discharge portion (230) is placed on the LED chip protection portion (225) and the LED chip protection portion (225) and the static electricity discharge portion (230) are heated so that the resin base (231) and the LED chip protection portion (225) are melted, the resin base (231) may be melted and mixed so as to become one with the LED chip protection portion (225).

[0111] The conductive pattern (233) can be liquefied by heating and penetrate into the interior of the LED chip protection member (225) that is fused with the resin base (231) and become immersed in the LED chip protection member (225). The conductive pattern (233) can be positioned spaced apart from a plurality of LED chips (220). When the LED chip protection member (225) is cured again, an LED display module (200) including the conductive pattern (233) immersed in the LED chip protection member (225) can be manufactured.

[0112] Since the LED chip protection member (225) is hardened while the conductive pattern (233) is immersed in the LED chip protection member (225), the LED display module (200) according to the second embodiment of the present invention may not include an additional conductive pattern protection member (140) (see FIGS. 1 and 2) that protects the conductive pattern (233).

[0113] Although not shown in FIGS. 10 to 12, the LED display module (200) may further include a transparent ITO layer laminated on the LED chip protection member (225). The material of the ITO layer may include transparent ITO, which is a transparent conductive material. The ITO layer may be laminated on the LED chip protection member (225) in the form of a flat film or a grid pattern. The ITO layer provides additional electrostatic capacity in addition to the conductive pattern (233), thereby helping to smoothly discharge static electricity of a higher voltage to the outside without damaging the LED display module (200) even if it is introduced.

[0114] Referring to FIG. 13, the LED display module (200) may further include an intra-module connection portion (250) that does not cover a plurality of LED chips (220) and electrically connects a conductive pattern (233) and a ground terminal (215).

[0115] The module-side connection portion (250) may include a corner-side connection portion (251) and a board-side connection portion (255). The board-side connection portion (255) is provided on the outer peripheral portion of the side where the ground terminal (215) is mounted on the circuit board (210) and may be electrically connected to the ground terminal (215). The corner-side connection portion (251) is provided at a corner of the LED display module (200). One end of the corner-side connection portion (251) may be electrically connected to the conductive pattern (233) and the other end may be electrically connected to the board-side connection portion (255).

[0116] The corner-side connecting portion (251) and the substrate-side connecting portion (255) may each include a metal layer (252, 256) and an opaque printing layer (253, 257). The material of the metal layers (252, 256) may include a conductive and glossy metal.

[0117] The opaque printing layer (253, 257) can cover the metal layer (252, 256) so that the metal layer (252, 256) is not exposed due to gloss. The opaque printing layer (253, 257) can be laminated by printing an opaque paint, such as black, on the metal layer (252, 256).

[0118] One end of the metal layer (252) of the corner-side connecting portion (251) can be electrically connected to the first fine line portion (234) or the second fine line portion (235) of the conductive pattern (233). One end of the metal layer (256) of the board-side connecting portion (255) can be electrically connected to the ground terminal (215), and the other end of the metal layer (256) of the board-side connecting portion (255) can be electrically connected to the other end of the metal layer (252) of the corner-side connecting portion (251). A through hole (214) penetrating the power connector (213) can be formed in the power connector (213) so that the metal layer (256) extends to the ground terminal (215).

[0119] The metal layer (256) of the substrate-side connection portion (255) can be prepared by laminating a metal layer on the surface of the circuit board (210) or by removing the PSR (photo solder resist) laminated on the outer periphery of the circuit board (210) from among the PSR laminated on the surface of the circuit board (210) to partially expose the metal layer of the circuit board (210).

[0120] FIG. 14 illustrates another example of an intra-module connection (260) that may be included in an LED display module (200) in place of the intra-module connection (250) illustrated in FIG. 13. Referring to FIG. 14, the intra-module connection (260) may include a corner-side connection (261), a substrate-side connection (264), a via-hole connection terminal (265), and a via-hole (267).

[0121] The substrate-side connecting portion (264) may be formed to extend along a path that avoids the plurality of LED chips (220) on the side where the plurality of LED chips (220) are mounted on the circuit board (210). The corner-side connecting portion (261) is provided at the corner of the LED display module (200). One end of the corner-side connecting portion (261) may be electrically connected to the conductive pattern (233), and the other end may be electrically connected to the substrate-side connecting portion (264).

[0122] The corner-side connecting portion (261) and the substrate-side connecting portion (264) may include a metal layer and an opaque printing layer, similar to the corner-side connecting portion (251) and the substrate-side connecting portion (255) illustrated in FIG. 13.

[0123] The via hole (267) includes a conductive metal and extends to penetrate the circuit board (210) in the thickness direction. One end of the via hole (267) can be conductively connected to a ground terminal (215). The via hole connection terminal (265) is provided at an end of the board-side connection portion (264) and can be conductively connected to the other end of the via hole (267).

[0124] Referring to FIG. 15, an LED display device may include a plurality of LED display modules (200, 202) having a rectangular planar shape. The plurality of LED display modules (200, 202) may be arranged adjacently in a matrix to form a large screen. Among the plurality of LED display modules (200, 202), a pair of adjacent LED display modules (200, 202) may each include an inter-module connection portion (270) that is electrically connected to a conductive pattern (233) of the adjacent LED display module (200, 202).

[0125] The inter-module connection (270) may include an inter-module terminal (271) and a corner connection (274). The corner connection (274) may be provided at a corner of the LED display module (200). One end of the corner connection (274) may be electrically connected to the conductive pattern (233).

[0126] An inter-module terminal (271) may be provided at a corner side of the circuit board (210). The inter-module terminal (271) may be electrically connected to the other end of the corner-side connecting portion (274). When a pair of LED display modules (200, 202) are arranged adjacent to each other, the inter-module terminal (271) of one LED display module (200) and the inter-module terminal (271) of the other LED display module (202) may be electrically connected by making contact.

[0127] Accordingly, when static electricity is introduced into one LED display module (200) included in the LED display device, the static electricity is dispersed to all LED display modules (200, 202) included in the LED display device and can be discharged to the outside through the ground electrode (215).

[0128] FIG. 16 illustrates another example of an inter-module connection (280) that may be included in an LED display module (200) in place of the inter-module connection (270) illustrated in FIG. 15. Referring to FIG. 16, the inter-module connection (280) may include an inter-module terminal (281) that is electrically connected to the conductive pattern (233). The inter-module terminal (281) may be provided on the outer periphery of the static electricity discharge unit (230).

[0129] When a pair of LED display modules (200, 202) are placed adjacent to each other, the inter-module terminal (281) of one LED display module (200) and the inter-module terminal (281) of the other LED display module (202) can be connected to each other so as to be electrically conductive.

[0130] Accordingly, when static electricity is introduced into one LED display module (200) included in the LED display device, the static electricity is dispersed to all LED display modules (200, 202) included in the LED display device and can be discharged to the outside through the ground electrode (215).

[0131] Referring to FIGS. 10, 17, and 18, a method for manufacturing an LED display module (200) according to a second embodiment of the present invention includes an LED chip mounting step (S210), an LED chip protection part forming step (S220), and an electrostatic discharge part bonding step (S230).

[0132] The LED chip mounting step (S210) is a step of mounting a plurality of LED chips (220) on one side of a circuit board (210). The LED chip mounting step (S210) can be performed using surface mount technology (SMT).

[0133] The LED chip protection part forming step (S220) is a step of forming an LED chip protection part (225) that surrounds and covers a plurality of LED chips (220) so that the plurality of LED chips (220) are sealed and laminated on the circuit board (210). For example, a transparent thermoplastic resin such as epoxy can be applied to one side of the circuit board (210) on which a plurality of LED chips (220) are mounted and cured to form the LED chip protection part (225).

[0134] The electrostatic discharge unit bonding step (S230) is a step of bonding the electrostatic discharge unit (230) including the conductive pattern (233) to the LED chip protection unit (225) so that the conductive pattern (233) is immersed in the LED chip protection unit (225). The electrostatic discharge unit (230) may further include a resin base (231) that supports the conductive pattern (233).

[0135] The electrostatic discharge unit bonding step (S230) may include a step in which at least a portion of the resin base (231) and at least a portion of the LED chip protection unit (225) are liquefied and fused together.

[0136] When a worker seals multiple LED chips (220) and places the static discharge unit (230) on the hardened LED chip protection unit (225), and heats the LED chip protection unit (225) and the static discharge unit (230) so that the resin base (231) and the LED chip protection unit (225) melt, the resin base (231) can melt and mix with the LED chip protection unit (225) to become one.

[0137] The conductive pattern (233) can be liquefied by heating and penetrate into the interior of the LED chip protection member (225) that is fused with the resin base (231) and become immersed in the LED chip protection member (225). The conductive pattern (233) can be positioned spaced apart from a plurality of LED chips (220).

[0138] The worker can cool the LED display module (200) or leave it at room temperature so that the LED chip protection member (225) and the resin base (231) can be hardened again. This allows the manufacturing of an LED display module (200) including a conductive pattern (233) immersed in the LED chip protection member (225).

[0139] As for the manufacturing method of the static electricity discharge unit (230), it has been described in the description of the LED display module (200) according to the second embodiment of the present invention, so any duplicate description will be omitted.

[0140] The LED display module (100, 200) described above includes an LED chip protection unit (125, 225) made of a resin material to physically protect a plurality of LED (120, 220) chips, and a static electricity discharge unit (130, 230) spaced apart from the plurality of LED chips (120, 220) discharges high voltage such as static electricity to the outside so that it does not flow into the inside.

[0141] Accordingly, multiple LED chips (120, 220) and circuit boards (110, 210) can be physically and electrically protected, and durability can be improved. In addition, the static electricity discharge unit (130, 230) can shield external EMI, further improving durability.

[0142] While the present invention has been described with reference to the embodiments illustrated in the drawings, these are merely exemplary, and those skilled in the art will appreciate that various modifications and equivalent embodiments are possible. Therefore, the true scope of protection of the present invention should be defined solely by the appended claims.

Claims

1. Circuit board; A plurality of LED chips mounted on one side of the circuit board; An LED chip protection member laminated on the circuit board, surrounding and covering a plurality of the LED chips so that the plurality of the LED chips are sealed; and An LED display module characterized by including a conductive pattern made of a conductive material and having a flat shape that does not cover a plurality of the LED chips, and an electrostatic discharge unit laminated on the LED chip protection unit.

2. In paragraph 1, An LED display module characterized in that the electrostatic discharge unit further includes a resin base that includes a transparent resin and supports the conductive pattern and is supported by the LED chip protection unit.

3. In paragraph 1, An LED display module characterized in that the above-mentioned conductive pattern includes a plurality of intersecting first micro-line portions and a plurality of second micro-line portions.

4. In paragraph 3, An LED display module characterized in that the width of the first fine line portion and the width of the second fine line portion are smaller than the spacing between adjacent pairs of LED chips among the plurality of LED chips.

5. In paragraph 3, The above-mentioned challenging material includes a shiny metal, An LED display module characterized in that the conductive pattern further includes an opaque printing layer covering the plurality of first fine line portions and the plurality of second fine line portions so that the plurality of first fine line portions and the plurality of second fine line portions are not visible.

6. In paragraph 1, An LED display module characterized in that the above conductive material includes at least one of copper (Cu), silver (Ag), gold (Au), and ITO (Indium Tin Oxide).

7. In paragraph 1, a ground terminal mounted on the other side of the circuit board; and An LED display module further comprising a module-internal connecting portion that does not cover the plurality of LED chips and electrically connects the conductive pattern and the ground terminal.

8. In paragraph 7, An LED display module characterized in that the connecting portion within the module includes a metal that can conduct electricity and includes a metal layer provided on the outer periphery of the circuit board.

9. In paragraph 8, An LED display module characterized in that the connecting part within the module further includes an opaque printing layer covering the metal layer so that the metal layer is not visible.

10. In paragraph 7, An LED display module characterized in that the connection part within the module includes a via hole that includes a conductive metal and extends to penetrate the circuit board in the thickness direction.

11. In paragraph 1, The above LED display modules are provided in multiple numbers, and a pair of LED display modules among the multiple LED display modules are arranged adjacently, An LED display module characterized in that the LED display module further includes an inter-module connection portion that is electrically connected to the conductive pattern of an adjacent LED display module.

12. LED chip mounting step of mounting multiple LED chips on one side of a circuit board; An LED chip protection part forming step for forming an LED chip protection part that surrounds and covers a plurality of the LED chips so that the plurality of the LED chips are sealed and is laminated on the circuit board; and A method for manufacturing an LED display module, comprising: a step of laminating an electrostatic discharge portion having a flat shape that does not cover a plurality of the LED chips and including a conductive pattern made of a conductive material, on the LED chip protection portion.

13. In paragraph 12, The above electrostatic discharge unit is made of a transparent resin and further includes a resin base that supports the conductive pattern, A method for manufacturing an LED display module, characterized in that the electrostatic discharge part laminating step includes a step of bonding the resin base to the LED chip protection part using an adhesive.

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