CN203026503U - LED device for display screen and display module - Google Patents

Abstract

An LED device for a display screen, comprising a first light-emitting unit, a second light-emitting unit, a third light-emitting unit, and a fourth light-emitting unit, and two sets of conductive circuit layers, the first light-emitting unit and the second light-emitting unit constitute a first Light-emitting area, the third light-emitting unit and the fourth light-emitting unit constitute the second light-emitting area, each light-emitting unit includes a red LED chip, a green LED chip and a blue LED chip, and each group of conductive circuit layers includes four mutually insulated Lead wires, the red LED chip, the green LED chip and the blue LED chip of the two light-emitting units in each light-emitting area are connected in antiparallel respectively, and are electrically connected with one group of conductive circuit layers. In addition, the utility model also provides a display module, which includes a plurality of LED device arrays for display screens. The LED device and the display module thereof of the utility model are beneficial to improving welding flatness and bringing convenience to maintenance.

Description

LED device and display module for display screen

technical field

The utility model belongs to the manufacturing field of light-emitting devices, and relates to an LED device for a display screen and a display module composed of the LED device. the

Background technique

Light-emitting diode (LED) light sources have the advantages of high efficiency, long life, and no harmful substances such as Hg. With the rapid development of LED technology, the brightness and lifespan of LEDs have been greatly improved, making the application of LEDs more and more extensive. From outdoor lighting such as street lamps to indoor lighting such as decorative lamps, they are all used or replaced one after another. into LED as light source. the

In addition, LED display (LED Panel) is also favored by people, and has been developed rapidly in recent years. It is widely used in large squares, financial markets, airports, banks, hospitals and shopping malls. This is because the LED display has many unique advantages, such as: high brightness, low working voltage, low power consumption, miniaturization, long life, stamping resistance and stable performance. the

According to the application site, LED display is divided into outdoor display, indoor display and semi-outdoor display. Among them, the area of indoor display screens generally ranges from less than 1 square meter to tens of square meters, and the dot density is relatively high. When used in non-direct sunlight or lighting environments, the viewing distance is several meters away. If it is divided according to the display color, it can be divided into monochrome, double-primary color and three-primary color (full color). Tricolor LED devices are the most widely used in indoor display screens. At present, people use very small three-primary-color LEDs, such as LEDs with a specification of 1010 (1.0mm×1.0mm), and can make dot pitches below P2.0 (the center-to-center distance between adjacent three-primary-color LEDs is 2.0mm). The indoor display screen greatly improves the resolution of the indoor display screen. Please refer to FIG. 1 , which is a schematic wiring diagram of a tri-primary LED device in the prior art. The three-primary-color LED device includes three LED chips of red, green and blue. One end of the three chips is respectively connected to an electrode end, and the other end is connected to an electrode end in common. Therefore, four electrode ends are required to drive it to emit light. When the LED display screen needs to arrange and weld multiple LED device arrays together, in order to facilitate the arrangement of the LED devices, the four electrodes of the LED devices are located on the same side. the

However, with the improvement of the resolution of the indoor display screen, the size of the LED device becomes smaller. When multiple LED devices are arranged in an array, multiple pins increase the difficulty of welding the LED device, and it is easy to occur when multiple LED devices are welded together. short circuit phenomenon. the

Therefore, it is necessary to find a new type of LED device for display screens and its display module, which can overcome the welding problem caused by small-sized LED devices without reducing the resolution of indoor display screens. the

Utility model content

The purpose of the utility model is to overcome the shortcomings and deficiencies in the prior art, and provide a small-sized LED device with high resolution and reduced welding difficulty. the

The utility model is realized through the following technical solutions: an LED device for a display screen, comprising a first light-emitting unit, a second light-emitting unit, a third light-emitting unit and a fourth light-emitting unit, and two sets of conductive circuit layers. A light-emitting unit and a second light-emitting unit form a first light-emitting area, and the third light-emitting unit and a fourth light-emitting unit form a second light-emitting area, and each light-emitting unit includes a red LED chip, a green LED chip and a blue LED chip respectively, Each group of conductive circuit layers includes 4 mutually insulated leads, and the red LED chips, green LED chips and blue LED chips of the two light-emitting units in each light-emitting area are respectively connected in reverse parallel, and electrically connected to one group of conductive circuit layers. connect. the

Wherein, the four leads of each group of conductive circuit layers extend to the same side of the LED device, or respectively extend to at least two different sides or corners of the LED device to form electrodes. the

Further, the LED device includes a printed circuit board, and the conductive circuit layer is arranged on the upper surface of the printed circuit board. The printed circuit board is provided with a through hole at the electrode formed by the conductive circuit layer, and the lower surface of the printed circuit board is provided with a terminal at the through hole, and the terminal is electrically connected with the electrode through the conductive layer in the through hole. the

Further, the conductive circuit layer of the first light-emitting area includes a first lead, a second lead, a third lead and a fourth lead that are insulated from each other, and the red LED chip, the green LED chip and the blue LED chip of the first light-emitting unit It is arranged on the first lead, and the green LED chip and the blue LED chip are insulated from the first lead, and the negative electrode of the red LED chip is electrically connected to the first lead; the green chip of the second light emitting unit and the blue LED chip are arranged on the second lead and insulated therefrom, the red LED chip of the second light-emitting unit is arranged on the third lead, and its cathode is electrically connected to the third lead; the first light-emitting unit The negative electrode of the green LED chip and the positive electrode of the green LED chip of the second light-emitting unit are electrically connected to the fourth lead through metal wires; the positive electrode of the green LED chip of the first light-emitting unit is connected to the second lead. The negative electrode of the green LED chip of the light-emitting unit is electrically connected to the third lead through a metal wire, and the negative electrode of the blue LED chip of the first light-emitting unit and the positive electrode of the blue LED chip of the second light-emitting unit are respectively connected through a metal wire. The wire is electrically connected to the second lead; the positive electrode of the blue LED chip of the first light emitting unit and the negative electrode of the blue LED chip of the second light emitting unit are respectively electrically connected to the third lead through a metal wire; the first light emitting The positive electrode of the red LED chip of the unit is electrically connected to the third lead through a metal wire, and the positive electrode of the red LED chip of the second light emitting unit is electrically connected to the first lead through a metal wire; the structure of the second light emitting area The structures of the first light-emitting area are distributed mirror-symmetrically along the central axis of the printed circuit board. the

Further, the LED device for the display screen further includes an encapsulant; the encapsulant covers the first light emitting unit, the second light emitting unit, the third light emitting unit and the fourth light emitting unit separately or entirely. the

And, the first light-emitting unit, the second light-emitting unit, the third light-emitting unit and the fourth light-emitting unit form a 2x2 array distribution, and the plurality of LED chips of the first light-emitting unit and the second light-emitting unit are linearly and equidistantly arranged. Multiple LED chips of the third light-emitting unit and the fourth light-emitting unit are linearly and equidistantly arranged. the

In addition, the utility model also provides an LED display module, which is composed of arrays of multiple LED devices. The LED device includes a first light-emitting unit, a second light-emitting unit, a third light-emitting unit and a fourth light-emitting unit, and two sets of conductive circuit layers. The first light-emitting unit and the second light-emitting unit form a first light-emitting area, and the third The light-emitting unit and the fourth light-emitting unit constitute the second light-emitting area. Each light-emitting unit includes a red LED chip, a green LED chip and a blue LED chip respectively. Each group of conductive circuit layers includes four mutually insulated leads. Each light-emitting area The red LED chip, the green LED chip and the blue LED chip of the two light emitting units are connected in antiparallel respectively, and are electrically connected with one group of conductive circuit layers. the

Compared with the prior art, the LED device of the present invention includes 4 light-emitting units. By connecting the positive and negative electrodes of the same-color LED chip of the two light-emitting units in parallel, only 8 electrodes can be used to drive the 4 light-emitting units, reducing the Reduce the number of electrodes by half, on the one hand, it can save the cost of LED device manufacturing and welding installation, on the other hand, it can reduce the difficulty of the installation process, avoid the solder joints caused by the adjacent electrode parts being too close to each other, and also make the design smaller The display screen has created good conditions with LED devices. the

In order to understand the utility model more clearly, the specific implementation of the utility model will be described below in conjunction with the accompanying drawings. the

Description of drawings

Fig. 1 is a schematic wiring diagram of a tri-primary LED device in the prior art. the

Fig. 2 is a schematic diagram of the wiring of the LED device in Embodiment 1 of the present invention. the

FIG. 3 is a schematic circuit diagram of the first light emitting area shown in FIG. 2 . the

Fig. 4 is a sectional view along C-C direction shown in Fig. 2 . the

Fig. 5 is a schematic diagram of wiring of an LED device according to Embodiment 2 of the present invention. the

Fig. 6 is a schematic diagram of wiring of an LED device according to Embodiment 3 of the present invention. the

Fig. 7 is a schematic structural diagram of the LED display module of the present invention. the

Detailed ways

Example 1

Please refer to FIG. 2 , which is a schematic diagram of the wiring of the LED device in Embodiment 1 of the present invention. The LED device 10 includes a printed circuit board 11, a conductive circuit layer 12 arranged on the printed circuit board 11, a first light-emitting unit 13a electrically connected to the conductive circuit layer 12, a second light-emitting unit 13b, a third light-emitting unit 13c and The fourth light emitting unit 13d, and the encapsulant covering the light emitting unit 13 . the

The LED device 10 is divided into a first light-emitting area A and a second light-emitting area B which are bilaterally symmetrical, and the conductive circuit layer 12 of the first light-emitting area A and the conductive circuit layer 12 of the second light-emitting area B are arranged symmetrically. The first light emitting unit 13a, the second light emitting unit 13b, the third light emitting unit 13c and the fourth light emitting unit 13d are arranged in a 2×2 array. Wherein, the first light emitting unit 13a and the second light emitting unit 13b are arranged in a row in the first light emitting area A, and the third light emitting unit 13c and the fourth light emitting unit 13d are in a row and arranged in the second light emitting area B. Each of the light emitting units 13a, 13b, 13c and 13d has the same structure, including at least one red LED chip R1, R2, R3, R4, at least one green LED chip G1, G2, G3, G4 and at least one blue LED chip Chips B1, B2, B3, B4, the plurality of LED chips are linearly and equidistantly arranged. Specifically, the LED chips of the first light emitting unit 13a and the second light emitting unit 13b are linearly arranged to form a row, and the LED chips of the third light emitting unit 13c and the fourth light emitting unit 13d are arranged linearly to form a row. Since the first light-emitting region A and the second light-emitting region B of the LED device 10 have a symmetrical structure, only the first light-emitting region A is taken as an example to describe its structure in detail. the

The conductive circuit layer 12 of the first light-emitting area A includes four mutually insulated leads, namely a first lead 121 , a second lead 122 , a third lead 123 and a fourth lead 124 . The red LED chip R1, the green LED chip G1 and the blue LED chip B1 of the first light emitting unit 13a are arranged on the first lead 121, and the green LED chip G1 and the blue LED chip B1 are bonded to the first lead 121 through an adhesive. The first lead 121 is insulated, and the cathode of the red LED chip R1 is electrically connected to the first lead 121 through silver paste. The green LED chip G2 and the blue LED chip B2 of the second light emitting unit 13b are disposed on the second lead 122 through an adhesive, and are insulated from the second lead 122 . The red LED chip R2 of the second light emitting unit 13 b is disposed on the third lead 123 , and its cathode is electrically connected to the third lead 123 through silver paste. the

The negative electrode of the green LED chip G1 of the first light emitting unit 13a and the positive electrode of the green LED chip G2 of the second light emitting unit 13b are respectively electrically connected to the fourth lead 124 through metal wires; the first light emitting unit 13a The positive electrode of the green LED chip G1 and the negative electrode of the green LED chip G2 of the second light emitting unit 13b are respectively electrically connected to the third lead 123 through metal wires. The negative electrode of the blue LED chip B1 of the first light emitting unit 13a and the positive electrode of the blue LED chip B2 of the second light emitting unit 13b are respectively electrically connected to the second lead 122 through metal wires; the blue light of the first light emitting unit 13a The positive electrode of the LED chip B1 and the negative electrode of the blue LED chip B2 of the second light emitting unit 13b are respectively electrically connected to the third lead 123 through metal wires. The positive electrode of the red LED chip R1 of the first light emitting unit 13a is electrically connected to the third lead 123 through a metal wire, and the positive electrode of the red LED chip R2 of the second light emitting unit 13b is connected to the first lead 121 through a metal wire. electrical connection. Please also refer to FIG. 3 , which is a schematic circuit diagram of the first light-emitting area A shown in FIG. 2 . The positive electrodes of the green LED chip G1, the blue LED chip B1 and the red LED chip R1 of the first light emitting unit 13a are connected to the positive electrodes of the green LED chip G2, the blue LED chip B2 and the red LED chip R2 of the second light emitting unit 13b. The negative electrode is electrically connected to the third lead 123 , and the third lead 123 extends to one side edge of the printed circuit board 11 to form a common electrode. The negative electrode of the green LED chip G1 of the first light emitting unit 13a and the positive electrode of the green LED chip G2 of the second light emitting unit 13b are connected to the fourth lead wire 124, and the fourth lead wire 124 extends to the printed circuit board 11 One side edge forms a green photoelectrode. The negative electrode of the blue LED chip B1 of the first light emitting unit 13a and the positive electrode of the blue LED chip B2 of the second light emitting unit 13b are electrically connected to the second lead 122, and the second lead 122 extends to the printed circuit board 11. A blue light electrode is formed on one side edge. The negative electrode of the red LED chip R1 of the first light emitting unit 13a and the positive electrode of the red LED chip R2 of the second light emitting unit 13b are electrically connected to the first lead 121, and the first lead 121 extends to the printed circuit board 11 One side edge forms a red photoelectrode. That is, the electrodes of the same-color LED chips of the first light-emitting unit 13a and the second light-emitting unit 13b are reversely connected in parallel, and when the high-frequency pulse is driven, the LED chips of the first light-emitting unit 13a and the second light-emitting unit 13b emit light alternately, Due to the delay of human vision, what the human eyes see is that two groups of light emitting units emit light at the same time. Then, only through four electrodes, two groups of light emitting units can be driven to emit light. In this embodiment, the red light electrode, the green light electrode, the blue light electrode and the common electrode are sequentially arranged on one side edge of the printed circuit board 11 . the

The structure of the second light-emitting area B and the structure of the first light-emitting area A are mirror-symmetrically distributed along the central axis of the printed circuit board 11 , and will not be repeated here. Therefore, in this embodiment, four groups of light-emitting units can be driven to emit light only by a total of eight electrodes arranged on both sides of the printed circuit board 11 , which reduces the size of the LED device and reduces the difficulty of its soldering. the

Please refer to FIG. 4 , which is a cross-sectional view along C-C direction shown in FIG. 2 . On the printed circuit board 11, there are through holes 112 that run through the upper and lower surfaces of the printed circuit board 11 at the red light electrode, blue light electrode, green light electrode and common electrode. The inner wall of the through hole 112 is covered with a conductive layer. On the printed circuit board The lower surface of 11 covers the through hole 112 with a terminal 114, and each electrode on the printed circuit board 11 is electrically connected to the terminal 114 through the conductive layer in the through hole 112, and is connected to an external power supply through the terminal 114. the

In this embodiment, the printed circuit board 11 is preferably black to improve the contrast of the display screen. The encapsulant can cover each light emitting unit 13 separately or completely cover the part of the LED device composed of four light emitting units. Wherein, it is preferable that the encapsulation colloid can cover each light-emitting unit 13 separately, so as to effectively reduce the stress generated by the encapsulation colloid, and the encapsulation colloid is preferably a black light-transmitting material. The metal wires connecting the LED chip and the conductive circuit layer 12 are preferably gold wires, alloy wires and the like. the

Example 2

Please refer to FIG. 5 , which is a schematic diagram of the wiring of the LED device in Embodiment 2 of the present invention. The wiring structure of the LED device in Embodiment 2 is substantially the same as that in Embodiment 1, the only difference being that: the first lead 121 of the first light-emitting area A extends to the upper edge of the printed circuit board 11 to form a red light electrode, the The third lead 123 extends to the lower edge of the printed circuit board 11 to form a common electrode, and the second lead 122 and the fourth lead 124 extend to the left edge of the printed circuit board to form a blue light electrode and a green light electrode. The structure of the second light-emitting area B is mirror-symmetrical to the structure of the first light-emitting area A along the central axis of the printed circuit board 11 . The LED device includes four light-emitting units, which are only driven by eight electrodes, and the eight electrodes are dispersedly arranged around the edges of the LED chip. The eight electrodes scattered around the edge of the device in this embodiment further have the following beneficial effects: (1) create conditions for the miniaturization design of the device volume; resolution, but it is not conducive to the circuit wiring design of the printed circuit board, and the distance between adjacent electrodes is too close, which is prone to short circuit phenomenon during soldering; and in this embodiment, eight electrodes are scattered around the edge of the LED chip, which increases the The spacing between adjacent electrodes creates favorable conditions for the design of small devices; (2) It is convenient for manufacturers to design printed circuit boards for LED device installation. the

Example 3

Please refer to FIG. 6 , which is a schematic diagram of the wiring of the LED device in Embodiment 2 of the present invention. The wiring structure of the LED device in Embodiment 2 is substantially the same as that in Embodiment 1, the only difference being that the first lead 121 of the first light-emitting area A extends to the upper left corner of the printed circuit board 11 to form a red light electrode, and the The third lead 123 extends to the lower edge of the printed circuit board 11 to form a common electrode, the second lead 122 extends to the lower left corner of the printed circuit board 11 to form a blue light electrode, and the fourth lead 124 extends to the left of the printed circuit board. The edge forms a green photoelectrode. The structure of the second light emitting area B is symmetrical to the mirror image structure of the first light emitting area A along the central axis of the printed circuit board 11 . The LED device includes four light-emitting units, which are only driven by eight electrodes, and the eight electrodes are dispersedly arranged at the corners and surrounding edges of the LED chip, further increasing the distance between the electrodes and reducing the difficulty of welding. the

Further, as a modified embodiment of the present utility model, the first lead, the second lead, the third lead and the fourth lead can extend to any side edge of the printed circuit board of the LED device to form electrodes, so as to maintain the distance between the electrodes. The optimal distance between them can reduce the difficulty of welding. the

Example 4

Please refer to FIG. 7 , which is a schematic structural diagram of the LED display module of the present invention. The LED display module includes a bottom plate, a mask 22 and a casing (not shown). Multiple LED devices 10 are arrayed on the base plate. The mask 22 is disposed above the LED device and fastened with the bottom plate. The mask 22 is provided with a pair of holes 221 , and the light emitting unit of the LED device 10 is exposed outside the pair of holes 221 . The distance between the light emitting units in each LED device 10 on the LED display module is equal, and the distance between adjacent light emitting units of two adjacent LED devices 10 is also equal. The distance D between two LED chips of the same color can reach 2.0 mm or less. the

Compared with the prior art, the LED device of the present utility model includes 4 light-emitting units, and the positive and negative electrodes of the same-color LED chip of the two light-emitting units are connected in parallel in opposite directions, combined with high-frequency pulses, only 8 electrodes are needed to drive 4 light-emitting units. One light-emitting unit reduces the number of electrodes by half. On the one hand, it can save the cost of manufacturing and welding and installing LED devices. On the other hand, it can reduce the difficulty of the installation process, avoiding the solder joints caused by the adjacent electrodes being too close together, and also reducing the difficulty of the installation process. Good conditions are created for designing LED devices for display screens with smaller volumes. the

Further, compared with the LED device adopting the same specifications, since the LED device of the present invention has four groups of red, green and blue light-emitting units, the distance between two adjacent groups of red, green and blue light-emitting units is the same, and the distance between each group of light-emitting units from the printed circuit board The edge distance is less than or equal to half of the distance between two adjacent groups of red, green and blue light emitting units, so one LED device of the present invention is equivalent to four red, green and blue LED devices, thereby achieving the effect of increasing the resolution by 4 times. the

And, the utility model adopts the bottom electrode terminal design based on the printed circuit board. When the LED device for the display screen is welded on the installation panel, the solder paste is only on the bottom of the circuit board, which can realize the seamless arrangement and welding of adjacent LED devices. Further increase the resolution of the display. the

The utility model is not limited to the above-mentioned embodiment, if the various modifications or deformations of the utility model do not depart from the spirit and scope of the utility model, if these changes and deformations belong to the claims of the utility model and within the equivalent technical scope, Then the utility model is also intended to include these modifications and variations. the

Claims (11)

1. A LED device for a display screen, characterized in that: comprising a first light-emitting unit, a second light-emitting unit, a third light-emitting unit and a fourth light-emitting unit, and two groups of conductive circuit layers, the first light-emitting unit and the second light-emitting unit Two light-emitting units form the first light-emitting area, the third light-emitting unit and the fourth light-emitting unit form the second light-emitting area, each light-emitting unit includes a red LED chip, a green LED chip and a blue LED chip, and each group of conductive circuit layers It includes 4 mutually insulated lead wires, and the red LED chips, green LED chips and blue LED chips of the two light emitting units in each light emitting area are respectively connected in reverse parallel and electrically connected with one group of conductive circuit layers. 2. The LED device for display screen according to claim 1, characterized in that: the four lead wires of each group of conductive circuit layers extend to the same side of the LED device, or extend to at least two of the LED device respectively. different sides or corners to form electrodes. 3. The LED device for a display screen according to claim 2, wherein the LED device comprises a printed circuit board, and the conductive circuit layer is disposed on the upper surface of the printed circuit board. 4. The LED device for display screen according to claim 3, characterized in that: the printed circuit board is provided with a through hole at the electrode formed by the conductive circuit layer, and the lower surface of the printed circuit board is provided at the through hole There is a terminal, which is electrically connected to the electrode through the conductive layer in the through hole. 5. The LED device for display screen according to any one of claims 1-4, characterized in that: the conductive circuit layer of the first light-emitting area includes a first lead wire, a second lead wire, a third lead wire insulated from each other. A lead wire and a fourth lead wire, the red LED chip, the green light LED chip and the blue light LED chip of the first light-emitting unit are arranged on the first lead wire, and the green light LED chip and the blue light LED chip are insulated from the first lead wire , the negative electrode of the red LED chip is electrically connected to the first lead; the green chip and the blue LED chip of the second light-emitting unit are arranged on the second lead and insulated therefrom; the red LED chip of the second light-emitting unit It is arranged on the third lead, and its negative electrode is electrically connected to the third lead; the negative electrode of the green LED chip of the first light emitting unit and the positive electrode of the green LED chip of the second light emitting unit are respectively passed through metal wires It is electrically connected to the fourth lead; the positive electrode of the green LED chip of the first light emitting unit and the negative electrode of the green LED chip of the second light emitting unit are respectively electrically connected to the third lead through metal wires, the first The negative electrode of the blue LED chip of the light-emitting unit and the positive electrode of the blue LED chip of the second light-emitting unit are electrically connected to the second lead through metal wires; the positive electrode of the blue LED chip of the first light-emitting unit is connected to the second lead. The negative electrode of the blue LED chip of the light-emitting unit is electrically connected to the third lead through a metal wire; the positive electrode of the red LED chip of the first light-emitting unit is electrically connected to the third lead through a metal wire, and the second light-emitting unit The positive electrode of the red LED chip is electrically connected to the first lead through a metal wire; the structure of the second light-emitting area and the structure of the first light-emitting area are mirror-symmetrically distributed along the central axis of the printed circuit board. 6. The LED device for a display screen according to claim 1, characterized in that: the LED device for a display screen further comprises an encapsulant; and the encapsulant covers the first light-emitting unit, the second light-emitting unit, the second light-emitting unit, respectively or as a whole. Three light-emitting units and a fourth light-emitting unit. 7. The LED device for display screen according to claim 6, characterized in that: the first light emitting unit, the second light emitting unit, the third light emitting unit and the fourth light emitting unit form a 2x2 array distribution, and the first light emitting unit The plurality of LED chips of the unit and the second light emitting unit are linearly and equidistantly arranged, and the plurality of LED chips of the third light emitting unit and the fourth light emitting unit are arranged linearly and equidistantly. 8. A display module, characterized in that it comprises a plurality of LED device arrays for any display screen as described in claims 1-6. 9. The display module according to claim 8, characterized in that: the display module further comprises a base plate and a mask, the LED device arrays for the plurality of display screens are arranged on the base plate, and the mask is arranged on the display screen On the top of the used LED device and fastened with the base plate, a pair of holes is arranged on the face cover, and the light-emitting unit of the LED device is exposed outside the pair of holes. 10. The display module according to claim 9, characterized in that the distances between adjacent light-emitting units of any two adjacent LED devices for display screens are equal. 11. The display module according to claim 10, characterized in that the distance between two adjacent LED chips of the same color in any two adjacent LED devices for display screens is less than 2.0 mm.

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