CN112447116A

CN112447116A - Transparent LED display screen and preparation method thereof

Info

Publication number: CN112447116A
Application number: CN201910823587.9A
Authority: CN
Inventors: 林富
Original assignee: Shenzhen Jinghong Technology Co ltd
Current assignee: Shenzhen Jinghong Technology Co ltd; GWS Technology Co Ltd
Priority date: 2019-09-02
Filing date: 2019-09-02
Publication date: 2021-03-05

Abstract

The invention provides a transparent LED display screen and a preparation method thereof, aiming at solving the problems that the distance between LED lamp beads cannot be reduced, the resolution of the transparent LED display screen cannot be improved and the transparency of the transparent substrate can be reduced to a certain extent by adopting a mode of forming a metal grid for supplying power on a transparent substrate as a power supply circuit in the transparent LED display screen in the prior art. The invention provides a transparent LED display screen, which comprises a transparent substrate and LED lamp beads, wherein the transparent substrate is provided with a transparent substrate; and welding a metal band on the transparent substrate close to the LED lamp bead, and electrically connecting the electrode pin bonding pad with the same polarity on the welding area of the lamp bead and the power supply bonding pad through the metal band. The transparent LED display screen provided by the invention can further reduce the space between the LED lamp beads and improve the resolution ratio of the LED lamp beads, and meanwhile, the metal belt with smaller occupied area has smaller obstruction to the sight, so that the extremely high permeability can be ensured.

Description

Transparent LED display screen and preparation method thereof

Technical Field

The invention relates to the field of LED display, in particular to the field of transparent LED display screens.

Background

Transparent LED displays are increasingly used in the market and various product forms are developed. A transparent LED display screen technology in which LED lamps are arrayed on a transparent substrate has started to appear. Transparent conductive materials such as metal mesh, nano silver, ITO and the like are generally used in the technology, but because the thickness of the materials attached to the transparent substrate is very thin, and the current demand of the LED during operation is high, the materials are difficult to meet the power supply demand of the LED, and especially when the LED array is densely arranged (the distance between the LED lamps is less than 10 mm), the power supply demand of the whole screen is difficult to meet. The operation of the LED lamps requires signal input control in addition to power supply, and therefore, connection of communication signal lines is required between the LED lamps, which results in more complicated circuit division on the substrate, and thus the circuit area of the power supply portion is reduced and the resistance is increased. Although there is also a technical solution to encapsulate the driving IC inside the LED lamp, thereby reducing the complexity of the circuit, at least 1 or 2 signal lines between the LED lamps are also needed, and in the case of dense arrangement of the LED lamps, the power supply requirement cannot be met after the circuit pattern layer is divided.

For example, as shown in fig. 1, an improved transparent LED display screen is provided, which includes a transparent substrate 1 ', a printed circuit layer 3 ' is disposed on the transparent substrate 1 ', and an array of LED beads 2 ' encapsulating chips is mounted on the transparent substrate 1 '; as shown in fig. 2, specifically, the printed circuit layer 3 'includes a lamp bead welding area 31', a power supply pad 32 ', a signal pad 33', and the like, 4 pads for mounting LED lamp bead pins are provided in the lamp bead welding area 31 ', in addition, two signal pin pads and two electrode pin pads are provided in each lamp bead welding area 31', the signal pin pads are connected in series through a printed signal line, and two electrode pin pads with opposite polarities are respectively supplied with power through a metal grid 30 'printed on the transparent substrate 1'.

This way has the advantage that the metal grid 30 'for power supply can be directly formed on the transparent substrate 1' as a power supply circuit by a printing process; however, since the thickness of the printed graphic layer 3 'is generally only about 35 microns, the current that each metal wire can bear on the formed metal grid 30' is very small, and when the distance between the LED lamp beads 2 'is smaller than 10mm, the power supply requirement of the LED lamp beads 2' is difficult to meet by the conductive capability of the metal wire. Therefore, the area of the metal grid 30 'has to be widened to meet the power supply requirement of the LED lamp, the space between the LED lamp beads 2' cannot be reduced, and the resolution of the transparent LED display screen cannot be improved; and the metal mesh 30 'may reduce the transparency of the transparent substrate 1' to some extent.

Disclosure of Invention

The invention provides a transparent LED display screen and a preparation method thereof, aiming at solving the problems that the distance between LED lamp beads cannot be reduced, the resolution of the transparent LED display screen cannot be improved and the transparency of the transparent substrate can be reduced to a certain extent by adopting a mode of forming a metal grid for supplying power on a transparent substrate as a power supply circuit in the transparent LED display screen in the prior art.

The invention provides a transparent LED display screen, which comprises a transparent substrate and LED lamp beads, wherein the transparent substrate is provided with a transparent substrate; the LED lamp bead comprises a support, a driving chip and a light-emitting wafer, wherein the driving chip and the light-emitting wafer are formed on the support; the LED lamp bead is also provided with a plurality of pins, and the pins comprise electrode pins and signal pins;

the transparent substrate is provided with a printed circuit layer; the printed circuit layer comprises a power supply bonding pad, a signal bonding pad and a lamp bead welding area which is arranged in an array and is used for installing LED lamp beads;

each lamp bead welding area is provided with a pin bonding pad corresponding to a pin of the LED lamp bead; the pin bonding pads comprise signal pin bonding pads and electrode pin bonding pads;

signal wires for signal transmission are arranged between the signal bonding pads and the signal pin bonding pads in the lamp bead welding areas and between the signal pin bonding pads of the lamp bead welding areas, so that control signals for controlling the on and off of the LED lamp beads can be transmitted in sequence through the LED lamp beads;

the transparent substrate is welded with a metal belt, the gap between the metal belt and the LED lamp beads is larger than 0mm and smaller than or equal to 1.5mm, and the metal belt is used for electrically connecting electrode pin pads with the same polarity on the welding area of the lamp beads and a power supply pad.

According to the transparent LED display screen provided by the invention, the metal belt is welded on the transparent substrate close to the LED lamp beads, the electrode pin bonding pads with the same polarity on the welding areas of the lamp beads are electrically connected with the power supply bonding pad to replace the metal grids printed on the transparent substrate to supply power to the LED lamp beads, so that the space between the LED lamp beads can be further reduced, the resolution ratio of the LED lamp beads is improved, meanwhile, the metal belt with smaller occupied area is vertically arranged, the sufficient electric conductivity of the whole line of LED lamps is ensured by enough cross-sectional area, the blocking of the sight is smaller, and the extremely high permeability can be ensured.

Furthermore, the upper plane of the metal belt and the upper plane of the LED lamp beads are located on the same plane or lower than the upper plane of the LED lamp beads.

Furthermore, N rows of M columns of lamp bead welding areas are arranged on the printed circuit layer;

m signal bonding pads are arranged on the printed circuit layer; the M signal bonding pads and the signal pin bonding pads in the N lamp bead welding areas on the same column are sequentially connected in series through signal lines;

or N signal pads are arranged on the printed circuit layer; and the N signal pads are sequentially connected in series with the signal pin pads in the M lamp bead welding areas on the same row through signal lines.

Furthermore, M pairs of power supply bonding pads or N pairs of power supply bonding pads are arranged on the printed circuit layer; each pair of the power supply pads comprises a first power supply pad and a second power supply pad with opposite polarities; the metal strips comprise M pairs or N pairs of first metal strips and second metal strips with opposite polarities;

the electrode pin bonding pads comprise a first electrode pin bonding pad and a second electrode pin bonding pad; a first epitaxial part is led out of the first electrode pin bonding pad; a second external extension part is led out of the second electrode pin bonding pad;

electrically connecting a first extension part of the first electrode pin bonding pad on the N lamp bead welding areas on the same column with a first power supply bonding pad with the same polarity through a first metal belt; electrically connecting a second extending part of the second electrode pin bonding pad on the lamp bead welding areas on the same row with a second power supply bonding pad with the same polarity through a second metal belt; or the first extension parts of the first electrode pin bonding pads on the M bead welding areas on the same row are electrically connected with the first power supply bonding pad with the same polarity through a first metal belt; and electrically connecting the second extending part of the second electrode pin pad on the lamp bead welding area on the same row with the second power supply pad with the same polarity through a second metal belt.

Furthermore, M +1 power supply bonding pads or N +1 power supply bonding pads are arranged on the printed circuit layer;

the M +1 power supply bonding pads or the N +1 power supply bonding pads comprise first power supply bonding pads and second power supply bonding pads which are arranged at intervals and have opposite polarities;

welding and electrically connecting a first extension part of the first electrode pin bonding pad on the N lamp bead welding areas on the same column with a first power supply bonding pad with the same polarity through a first metal belt; welding and electrically connecting second extending parts of the second electrode pin bonding pads on the N lamp bead welding areas on the same column with a second power supply bonding pad with the same polarity through a second metal belt; the first metal belt and the second metal belt are arranged at intervals; or the first extension parts of the first electrode pin bonding pads on the M bead welding areas on the same row are electrically connected with the first power supply bonding pad with the same polarity in a welding mode through a first metal belt; and welding and electrically connecting second extending parts of the second electrode pin bonding pads on M lamp bead welding areas on the same row with second power supply bonding pads with the same polarity through second metal strips, wherein the first metal strips and the second metal strips are arranged at intervals.

Furthermore, the first metal belt and the second metal belt are arranged in parallel at intervals with the bead welding areas on each row; the first extension part and the second extension part on each lamp bead welding area are respectively and electrically connected with the first metal belt and the second metal belt outside the left side and the right side of each lamp bead welding area; the lamp bead welding areas on adjacent rows are connected into a whole by the extension parts of the metal strips sharing the same polarity;

or the first metal belt and the second metal belt are arranged at intervals with the bead welding areas on each row; the first extension part and the second extension part on each lamp bead welding area are respectively and electrically connected with the first metal belt and the second metal belt outside the upper side and the lower side of each lamp bead welding area; wherein, the extension parts of the metal strips sharing the same polarity between the bead welding areas on the adjacent rows are connected into a whole.

Furthermore, the signal pin bonding pad on each lamp bead welding area at least comprises a first signal input pin bonding pad and a first signal output pin bonding pad;

m signal bonding pads are arranged on the printed circuit layer; the M signal pads are sequentially connected in series with a first signal input pin pad and a first signal output pin pad in the N lamp bead welding areas on the same column through signal lines;

or N signal pads are arranged on the printed circuit layer; the N signal bonding pads are sequentially connected in series with first signal input pin bonding pads and first signal output pin bonding pads in M lamp bead welding areas on the same column through signal lines.

Furthermore, a sealing adhesive layer and a transparent cover plate are further arranged on the transparent substrate.

Further, the width of the metal strip is 0.03-1.5 mm.

The invention provides a preparation method of a transparent LED display screen, which comprises the following steps:

step S1, printed circuit layer forming step: forming a printed circuit layer on a transparent substrate; the printed circuit layer comprises a power supply bonding pad, a signal bonding pad and a lamp bead welding area which is arranged in an array and is used for installing LED lamp beads;

step S2, LED lamp bead installation step: welding the LED lamp beads in the lamp bead welding area of the printed circuit layer;

step S3, metal strip welding step: welding a metal band on the printed circuit layer, wherein the gap between the metal band and the LED lamp bead is larger than 0 and less than or equal to 1.5mm, and electrically connecting an electrode pin pad and a power supply pad with the same polarity on the welding area of the lamp bead through the metal band;

step S4, packaging step: and packaging the printed circuit layer welded with the LED lamp beads.

According to the preparation method of the transparent LED display screen, the metal belt is welded on the transparent substrate close to the LED lamp beads, the electrode pin bonding pads with the same polarity on the welding area of the lamp beads and the power supply bonding pads are electrically connected to replace metal grids printed on the transparent substrate to supply power to the LED lamp beads, so that the space between the LED lamp beads can be further reduced, the resolution ratio of the LED lamp beads is improved, meanwhile, the metal belt with smaller occupied area blocks the sight line less, and extremely high permeability can be guaranteed.

Further, the step S1 specifically includes the following steps:

step S11, covering a copper foil on the transparent substrate;

and step S12, etching the copper foil to form the printed circuit layer.

Further, the step S4 specifically includes the following steps:

s41, pouring a transparent material on the printed circuit layer after the LED lamp beads are welded;

step S42, covering a transparent cover plate on the transparent material in the step S41;

and step S43, curing the transparent material in the step S41 through an oven to form a sealant layer.

Drawings

FIG. 1 is a schematic cross-sectional view of a transparent LED display screen provided in the prior art;

FIG. 2 is a schematic top view of a prior art transparent LED display screen;

FIG. 3 is a schematic top view of a printed circuit layer and a bonding metal strap on a transparent substrate of a first transparent LED display panel according to an embodiment of the present invention;

FIG. 4 is a schematic partial cross-sectional view of a first transparent LED display panel (without encapsulation) according to an embodiment of the present invention;

FIG. 5 is a schematic partial cross-sectional view of a first transparent LED display screen (after being encapsulated) according to an embodiment of the present invention;

FIG. 6 is an enlarged schematic view at A in FIG. 3;

fig. 7 is a schematic bottom view of an LED lamp bead provided in the embodiment of the present invention;

fig. 8 is a schematic front view of an LED lamp bead provided in the embodiment of the present invention;

FIG. 9 is a schematic top view of a printed circuit layer on a transparent substrate of a first transparent LED display panel according to an embodiment of the present invention;

FIG. 10 is an enlarged schematic view at B of FIG. 9;

fig. 11 is a schematic top view of a first transparent LED display screen provided in an embodiment of the present invention after being mounted with an LED lamp bead;

FIG. 12 is a schematic top view of a printed circuit layer on a transparent substrate of a second transparent LED display panel according to an embodiment of the present invention;

FIG. 13 is an enlarged schematic view at C of FIG. 12;

fig. 14 is a schematic top view of a second transparent LED display screen provided in an embodiment of the present invention after being mounted with an LED lamp bead;

fig. 15 is a schematic top view of a second transparent LED display screen provided in the embodiment of the present invention after LED beads are mounted and metal strips are welded;

fig. 16 is an enlarged schematic view at D in fig. 15.

Reference numerals in the background art:

1', a transparent substrate; 2', LED lamp bead; 3', printing a circuit layer; 30', a metal grid; 31', a lamp bead welding area; 32', a power supply pad; 33', signal pads;

reference numerals in the detailed description: 1. a transparent substrate; 2. LED lamp beads; 3. printing a circuit layer; 4. a metal strip; 5. a glue sealing layer; 6. a transparent cover plate;

21. a pin; 21a, a first electrode pin; 21b, a second electrode pin; 21c, a first signal input pin; 21d, a first signal output pin; 22. a driving chip; 23. a light emitting chip; 23R, a red light emitting wafer; 23G, green light emitting chips; 23B, a blue light emitting wafer;

31. a lamp bead welding area; 32. a power supply pad; 33. a signal pad; 34. a signal line; 31a, a first electrode pin pad; 31b, a second electrode pin pad; 31c, a first signal input pin pad; 31d, a first signal output pin pad; 311. an extension portion; 311a, a first extension portion; 311b, a second extension portion; 32a, a first power supply pad; 32b, a second power supply pad; 34a, a first track; 34b, a second track;

4a, a first metal strip; 4b, a second metal strip.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects solved by the present invention more clearly apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

In the description of the present invention, it is to be understood that the terms "longitudinal", "radial", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Example 1

As shown in fig. 3 and 4, the present example discloses a transparent LED display screen, which includes a transparent substrate 1 and LED beads 2; the LED lamp bead 2 comprises a support, a driving chip 22 and a light-emitting wafer 23, wherein the driving chip 22 and the light-emitting wafer are formed on the support; the LED lamp bead 2 is also provided with a plurality of pins 21, and the pins 21 comprise electrode pins and signal pins;

a printed circuit layer 3 is arranged on the transparent substrate 1; as shown in fig. 3 and 6, the printed circuit layer 3 includes a power supply pad 32, a signal pad 33, and bead lands 31 for mounting the LED beads 2, which are arranged in an array;

each lamp bead welding area 31 is provided with a pin pad corresponding to the pin 21 of the LED lamp bead 2; the pin bonding pads comprise signal pin bonding pads and electrode pin bonding pads;

signal wires 34 for signal transmission are arranged between the signal pads 33 and signal pin pads in the lamp bead welding areas 31 and between the signal pin pads of each lamp bead welding area 31, so that control signals for controlling the on and off of each LED lamp bead can be transmitted in sequence through each LED lamp bead 2; specifically, for example, signal lines 34 for signal transmission are provided between the signal pads 33 and the signal pin pads in the lamp bead lands 31, and between the signal pin pads in the adjacent lamp bead lands 31 in the same row or the same column; however, it is not limited that the adjacent LED beads 2 are connected by the signal line 34, and the LED beads 2 at the tail of one column are LED to the LED beads at the head of the adjacent column by the signal line 34 for connection, and the like, all of them are possible.

Transparent substrate 1 welding has strap 4, strap 4 with the clearance between LED lamp pearl 2 is greater than 0, less than or equal to 1.5mm, through strap 4 will the electrode pin pad and the power pad 32 electricity of homopolar on the lamp pearl welding zone 31 are connected.

As shown in fig. 5, after the LED lamp bead 2 is soldered to the corresponding lamp bead soldering area 31 on the printed circuit layer 3 by the surface mounting technology, a layer of sealant layer 5 is integrally packaged on the surface of the LED lamp bead. Further, according to the requirement, a transparent cover plate 6 can be arranged on the upper edge of the sealing glue layer 5. And the wire harness is led out from the power supply bonding pad 32 and the signal bonding pad 33, and the edge between the transparent cover plate 6 and the transparent substrate 1 is sealed and packaged, so that the waterproof effect is achieved. The sealant layer 5 may be obtained by casting and hardening a transparent material, for example, epoxy resin, transparent silicone, or other transparent materials may be used. The transparent cover 6 is generally made of glass or alternatively a transparent part made of printed plastic material. Cover behind the rubberizing layer 5 at transparent substrate 1 and cover transparent cover 6 again, can guarantee fine gas tightness, be difficult to let the steam invasion lead to LED lamp pearl 2 to make its inefficacy.

For example, fig. 7-8 disclose an LED lamp bead 2 packaged with a driving chip 22 and having 4 pins 21, where the pins 21 include two electrode pins and two signal pins; the electrode pins include a first electrode pin 21a and a second electrode pin 21 b; for example, the two electrode pins have opposite polarities, for example, the first electrode pin 21a serves as a positive electrode pin; the second electrode pin 21b serves as a negative electrode pin. The LED lamp bead is used for providing power for the light-emitting wafer 23 in the LED lamp bead 2; the two signal pins are respectively referred to as a first signal input pin 21c and a first signal output pin 21 d; the driving chip 22 is provided with an interface electrically connected to each light emitting chip 23 and each lead through a bonding wire.

In this example, the light emitting chips 23 include a red light emitting chip 23R, a green light emitting chip 23G, and a blue light emitting chip 23B; it is arranged in a straight line; of course, the arrangement can be in a delta shape.

Of course, depending on the control method, there may be a plurality of signal pins for controlling signal input and output.

The form of the metal strip 4 is not particularly limited. For example, the cross section of the metal strip 4 includes a circle, a semicircle, a triangle, an ellipse, a quadrangle, or other regular or irregular polygon. Through this kind of mode, can effectively adjust its strap 4's width and height, make the width less relatively, and promote its height, guarantee its power supply demand on the one hand, simultaneously, can not influence its transparent display screen's whole penetrating effect again. In this example, the metal strip 4 has a quadrangular cross section, wherein the width of the metal strip 4 is 0.03 to 1.5mm and the height thereof is 1 to 2 mm. Within the size range, the power supply requirement of the whole column of LED lamp beads 2 can be ideally met, and the power supply requirement is many times stronger than the power supply capacity of other transparent conductive materials. Meanwhile, the blocking of the sight is small, and high permeability can be guaranteed. For example, in this embodiment, the metal strip 4 has a width of 0.5mm, a height of 1.2mm, a cross-sectional area of 0.6mm2, and is equivalent to a copper wire with a diameter of 1.6mm, and has a strong conductive capability. The metal tape 4 is not particularly limited to a specific material, and may be a metal having high conductivity. In this case, copper tape is preferably used.

In this example, the upper plane of the metal band 4 and the upper plane of the LED lamp bead 2 are located on the same plane or lower than the upper plane of the LED lamp bead 2. In this way, the metal strip 4 does not block light.

By adopting the power supply mode of the metal belt 4 provided by the embodiment, the size of the LED lamp beads 2 can be further reduced, and the gaps between the LED lamp beads 2 are reduced, for example, the length of the LED lamp beads is 1-5mm, and the width of the LED lamp beads is 1-5 mm. . The gap between the LED lamp beads 2 is 3-10 mm. The gap mentioned here refers to the distance between the centers of the adjacent LED lamp beads 2, for example, the gap of the LED lamp bead 2 in this example may be 5 mm.

The transparent substrate 1 may be made of various rigid or flexible materials known in the public, such as a glass substrate, a PET (Polyethylene terephthalate) substrate, a PI (polyimide) film, and the like.

As shown in fig. 6, the power supply pad 32 in this example is used for connecting with an externally connected dc power supply, and the dc power supply is connected to each LED lamp bead 2 through the power supply pad 32 by the metal strip 4 mentioned in this application; which includes a first power supply pad 32a and a second power supply pad 32b of opposite polarities; for example, in this example, the first power supply pad 32a is a positive electrode pad; the second power supply pad 32b is a negative electrode pad.

The power supply pads 32 may be provided with only two of opposite polarities, such as one first power supply pad 32a, one second power supply pad 32 b; the electrical connection of the pin pads of the same polarity on the bead bond region 31 on the power supply pads 32 distributed in an array can be realized by a plurality of metal strips 4. Or the power supply pads 32 can be provided in plurality, and the pin pads with the same polarity on the bead lands 31 in one row or one column can be electrically connected to one power supply pad 32 through the metal strip 4. Some examples will be given below.

Similarly, the signal pad 33 is used for connection with an external signal input source, which is usually connected to a control chip at a previous stage; the number of the signal pads 33 is not particularly limited, for example, only one signal pad 33 mentioned in the background art inputs a control signal through one signal pad 33, and then the control signal is sequentially transmitted to each LED lamp bead 2 connected in series through the signal line 34. Of course, it can be set according to the number of I/O ports on the control chip. For example, it is allowable that the same signal pad 33 is used for the LED lamp beads 2 in the same row or the same column, or the same signal pad 33 is used for the LED lamp beads 2 in multiple rows or multiple columns.

As the signal lines 34 defined herein, printed signal lines printed on the transparent substrate 1 may be ITO (Indium Tin oxide; Indium Tin Oxides) lines or silver paste lines or copper-clad lines, and in this example, a grid-like copper-clad line printed on the transparent substrate 1 may be used. Or point-to-point connection is formed by using a metal wire machine to beat up and remove flying wires. Similarly, the pads on the printed circuit layer 3 and the extension 311 can be made of transparent conductive material, such as metal mesh, ITO, nano silver, etc.

In particular, in practical production, if a copper-clad material is used for the signal line 34 and the epitaxial portion 311, a line width as small as 0.01mm can be achieved, the electric conductivity is sufficient for the power supply requirement and signal transmission of a single LED lamp, the blocking of the line of sight is extremely small, and the extremely high transparency of the whole LED display screen can be achieved.

The manner in which the metal strips 4 and the printed circuit lines are connected will be explained further below with reference to a specific preferred embodiment.

As shown in fig. 9 and 10, the printed circuit layer 3 is provided with N rows by M columns of bead lands 31; by way of example, assume N ═ 5; m is 5; in this example 5 x 5 bead lands 31 are printed on the transparent substrate 1. In order to make the present invention idea understood by those skilled in the art, the columns of bead weld zones 31 on the same row are called as a weld row; the columns of bead lands 31 on the same column will be referred to as solder columns.

In this example, 5 signal pads 33 are disposed on the printed circuit layer 3; the 5 signal pads 33 are connected in series with the signal pin pads in the 5 lamp bead welding areas 31 on the same column in sequence through signal lines 34; specifically, a first signal input pin pad 31c and a first signal output pin pad 31d are arranged in the lamp bead welding area 31; in the serial connection, the signal pad 33 on the corresponding row is connected to the first signal input pin pad 31c in the first lamp bead pad 31 on the row through a signal line 34 (for the sake of distinction, the signal line 34 is referred to as a first track 34a in this example); then, the 3 rd, 4 th and 5 th lamp bead lands 31 are connected in series by connecting a first signal output pin pad 31d in the first lamp bead land 31 to a first signal input pin pad 31c in a second lamp bead land 31 on the same column through a signal line 34 (in this example, the signal line 34 in the adjacent lamp bead land 31 is referred to as a second track 34 b). Of course, the way of concatenation is not necessarily limited to the same row or the same column. The signal lines 34 in this example are in a grid form, which can further increase the transparency of the transparent LED display.

In this example, as shown in fig. 9 and 10, 5 pairs of power pads 32 are disposed on the printed circuit layer 3; each pair of the power supply pads 32 includes a first power supply pad 32a and a second power supply pad 32b of opposite polarities;

as shown in fig. 9 and 10, the electrode pin pads in each of the bead lands 31 include a first electrode pin pad 31a and a second electrode pin pad 31 b; a first extension part 311a is led out of the first electrode pin pad 31 a; a second extending portion 311b is led out from the second electrode pin pad 31 b;

electrically connecting the first extension parts 311a of the first electrode pin pads 31a on the 5 lamp bead welding areas 31 on the same column with the first power supply pads 32a with the same polarity by welding through a first metal belt 4 a; and electrically connecting the second extending part 311b of the second electrode pin pad 31b on the lamp bead welding area 31 on the same column with the second power supply pad 32b with the same polarity by welding through a second metal belt 4 b.

After the LED lamp beads 2 are mounted on the printed circuit layer 3, the result is as shown in fig. 11, the LED lamp beads are electrically connected to the extending portion 311 extending from the electrode pin pad on the lamp bead soldering area 31 through the power supply pad 32 via the metal tape 4, and the current is electrically communicated from the electrode pin of the LED lamp beads 2 via the electrode pin pad to form a power supply loop. Meanwhile, the control signal flowing from the signal pad 33 flows through the LED lamp beads 2 connected in series in sequence, and is received by the previous LED lamp bead 2 and transmitted to the next LED lamp bead 2. So as to realize the control of the on-off and color change of the light-emitting wafer 23 on each LED lamp bead 2.

Then, metal bands 4 are welded on the printed circuit layer 3, so that the metal bands 4 with opposite polarities are welded on the left side and the right side of the LED lamp beads 2. The results are shown in FIG. 3. The metal band 4 is welded on the left side and the right side of the welding column formed by each LED lamp bead 2, and the gap between the metal band 4 and the LED lamp beads 2 is very small, so that the metal band 4 is close to the LED lamp beads 2.

As another embodiment, as shown in fig. 12 to 16, M +1 power pads 32 or N +1 power pads 32 may be disposed on the printed circuit layer 3;

in this example, N-M-5 is still used as an example. On the printed

circuit layer

3, 6 power supply pads 32 are arranged.

The 6 power supply pads 32 include first and second

power supply pads

32a and 32b arranged at intervals and having opposite polarities; as shown in fig. 12 and 13, 6 power pads 32 are disposed at the upper side of a row of bead lands 31, and include a first power pad 32a, a second power pad 32b, a first power pad 32a, and a second power pad 32b in sequence;

also, the electrode pin pads include a first electrode pin pad 31a and a second electrode pin pad 31 b; a first extension part 311a is led out of the first electrode pin pad 31 a; a second extending portion 311b is led out from the second electrode pin pad 31 b;

as shown in fig. 14, the LED lamp beads 2 are mounted on the bead lands 31 by a patch.

In this example, as shown in fig. 12 to 16, the extension portions 311 of the metal strips 4 sharing the same polarity between the bead lands 31 in adjacent columns are preferably integrally connected. For example, a first power supply pad 32a is disposed at an upper portion between the two adjacent rows, and a first metal strip 4a is led out from the first power supply pad 32 a; the first outer extension 311a on the bead lands 31 between two adjacent columns is extended as one body. Preferably, in order to prevent the first extension portion 311a from interfering with other signal lines 34 and the like, the first extension portion 311a may be passed through the inside of the 4 lead lands as shown by the left bead land 31 in fig. 13. In this example the first metal strip 4a is welded immediately to the left of the first row of weld columns and the second metal strip 4b is welded immediately to the left of the second row of weld columns. And metal strips 4 of opposite polarity are arranged at intervals in this order. The second metal strip 4b of the last column is welded immediately to the right of the fifth welding column. As a result, the gap between the metal band 4 and the LED lamp bead 2 is very small, and the metal band 4 is welded to the LED lamp bead 2 in a manner of abutting against the LED lamp bead.

Of course, the power pads 32 and the signal pads 33 may also be arranged in a row, and the first extension portions 311a of the first electrode pin pads 31a on the M bead lands 31 in the same row are electrically connected to the first power pads 32a with the same polarity by welding via the first metal strips 4 a; and electrically connecting the second extending part 311b of the second electrode pin pad 31b on the lamp bead welding area 31 on the same row with the second power supply pad 32b with the same polarity by welding through a second metal belt 4b, wherein the first metal belt 4a and the second metal belt 4b are arranged at intervals.

In this example, signal pin pads on the bead lands 31 are also connected by very fine wires as signal lines 34.

Then, the first extending portions 311a of the first electrode pin pads 31a on the 5 lamp bead welding areas 31 on the same column are electrically connected with the first power supply pads 32a with the same polarity through the first metal strips 4a in a welding manner; that is, the first extension portion 311a on the same bonding column is electrically connected to the first power supply pad 32a through the first metal tape 4 a; the second extending part 311b of the second electrode pin pad 31b on the lamp bead welding area 31 on the same column is electrically connected with the second power supply pad 32b with the same polarity by welding through a second metal belt 4 b; that is, the second extension portion 311b on the same bonding column is electrically connected to the second power supply pad 32b through the second metal tape 4 b; the first metal strip 4a and the second metal strip 4b are arranged at intervals; the first metal belt 4a and the second metal belt 4b are arranged in parallel at intervals with the bead welding areas 31 on each row; the first extension part 311a and the second extension part 311b on each lamp bead welding area 31 are respectively and electrically connected with the first metal belt 4a and the second metal belt 4b outside the left side and the right side of the first extension part and the second extension part;

the transparent LED display screen that this example provided, because it is close to on transparent substrate 1 LED lamp pearl 2 welding have strap 4 will homopolar electrode pin pad and power pad 32 electricity on the lamp pearl welding zone 31 are connected to replace the metal net of printing on transparent substrate 1 to come for each LED lamp pearl 2 power supplies, make it can further reduce the interval between each LED lamp pearl 2, promote its resolution ratio, simultaneously, the less strap 4 of area occupied is also less to the blockking of sight, can guarantee high permeability. And this strap 4 is close to LED lamp pearl 2 sets up, and this kind of mode can let strap 4 account for the proportion littleer in transparent display screen.

Example 2

The present example will specifically describe the preparation method of the transparent LED display screen provided in example 1, and the preparation method specifically includes the following steps:

step S1, printed circuit layer 3 forming step: forming a printed circuit layer 3 on a transparent substrate 1; the printed circuit layer 3 comprises a power supply bonding pad 32, a signal bonding pad 33 and a lamp bead welding area 31 for mounting the LED lamp beads 2, wherein the lamp bead welding area 31 is arranged in an array;

wherein, the step S1 specifically includes the following steps:

step S11, covering a copper foil on the transparent substrate 1; the thickness of the copper foil is 10-35 microns.

Step S12, etching the copper foil to form the printed circuit layer 3. And removing redundant copper foil to form a signal line and an extension part 311 among the lamp bead welding area 31, the power supply welding disc 32, the signal welding disc 33 and the LED welding disc area.

Step S2, LED lamp bead installation step: welding the LED lamp beads 2 in the lamp bead welding area 31 of the printed circuit layer 3; the mode of welding this LED lamp pearl 2 generally adopts surface mounting technique, fixes LED lamp pearl 2 in advance on printed circuit layer 3 back, then welds LED lamp pearl 2 on lamp pearl welding zone 31 through the mode of reflow soldering.

Step S3, metal strip welding step: welding a metal belt 4 on the printed circuit layer 3, and electrically connecting electrode pin bonding pads with the same polarity on the lamp bead welding area 31 and a power supply bonding pad 32 through the metal belt 4;

step S4, packaging step: and then the printed circuit layer 3 welded with the LED lamp beads 2 is packaged. Specifically, the step S4 specifically includes the following steps:

step S41, pouring a layer of transparent material on the printed circuit layer 3 after the LED lamp beads 2 are welded;

step S42, covering the transparent cover plate 6 on the transparent material in step S41;

and step S43, curing the transparent material in the step S41 through an oven to form the sealant layer 5.

According to the preparation method of the transparent LED display screen, the metal belt 4 is welded on the transparent substrate 1 close to the LED lamp beads 2 to electrically connect the electrode pin bonding pads with the same polarity on the lamp bead welding area 31 and the power supply bonding pad 32, so that the metal mesh printed on the transparent substrate 1 is replaced to supply power to the LED lamp beads 2, the space between the LED lamp beads 2 can be further reduced, the resolution ratio of the LED lamp beads is improved, meanwhile, the metal belt 4 with smaller occupied area blocks the sight line less, and extremely high permeability can be ensured. With this strap 4 close to LED lamp pearl 2 sets up, this kind of mode can let strap 4 shared proportion littleer in transparent display screen.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. A transparent LED display screen comprises a transparent substrate and LED lamp beads; the LED lamp bead is characterized by comprising a support, a driving chip and a light-emitting wafer, wherein the driving chip and the light-emitting wafer are formed on the support; the LED lamp bead is also provided with a plurality of pins, and the pins comprise electrode pins and signal pins;

2. The transparent LED display screen of claim 1, wherein the upper plane of the metal strip and the upper plane of the LED lamp bead are on the same plane or lower than the upper plane of the LED lamp bead.

3. The transparent LED display screen of claim 2, wherein N rows by M columns of bead lands are provided on the printed circuit layer;

4. The transparent LED display screen of claim 3, wherein M pairs of power pads or N pairs of power pads are disposed on the printed circuit layer; each pair of the power supply pads comprises a first power supply pad and a second power supply pad with opposite polarities; the metal strips comprise M pairs or N pairs of first metal strips and second metal strips with opposite polarities;

5. The transparent LED display screen of claim 3, wherein M +1 power pads or N +1 power pads are disposed on the printed circuit layer;

6. The transparent LED display screen of claim 5, wherein the first metal strip and the second metal strip are arranged in parallel rows at intervals with the bead soldering areas on each row; the first extension part and the second extension part on each lamp bead welding area are respectively and electrically connected with the first metal belt and the second metal belt outside the left side and the right side of each lamp bead welding area; the lamp bead welding areas on adjacent rows are connected into a whole by the extension parts of the metal strips sharing the same polarity;

or the first metal belt and the second metal belt are arranged in parallel with the bead welding areas on each row at intervals; the first extension part and the second extension part on each lamp bead welding area are respectively and electrically connected with the first metal belt and the second metal belt outside the upper side and the lower side of each lamp bead welding area; wherein, the extension parts of the metal strips sharing the same polarity between the bead welding areas on the adjacent rows are connected into a whole.

7. The transparent LED display screen of claim 3, wherein the signal pin pads on each lamp bead lands comprise at least a first signal input pin pad and a first signal output pin pad;

8. The transparent LED display screen of claim 2, wherein the transparent substrate is further provided with a sealant layer and a transparent cover plate.

9. The transparent LED display screen of claim 2, wherein the metal strip has a width of 0.03-1.5 mm.

10. A preparation method of a transparent LED display screen is characterized by comprising the following steps:

11. The method for manufacturing the transparent LED display screen according to claim 10, wherein the step S1 specifically comprises the following steps:

step S11, covering a copper foil on the transparent substrate;

and step S12, etching the copper foil to form the printed circuit layer.

12. The method for manufacturing the transparent LED display screen according to claim 10, wherein the step S4 specifically comprises the following steps: