CN217640573U

CN217640573U - LED display module and LED display screen

Info

Publication number: CN217640573U
Application number: CN202221357989.8U
Authority: CN
Inventors: 陈锐冰
Original assignee: Huizhou Jufei Optoelectronics Co ltd
Current assignee: Huizhou Jufei Optoelectronics Co ltd
Priority date: 2022-05-31
Filing date: 2022-05-31
Publication date: 2022-10-21
Anticipated expiration: 2032-05-31

Abstract

The utility model relates to a LED display module and LED display screen, wherein the front of the circuit base plate of LED display module is equipped with a plurality of pixel units, still be equipped with the black layer that has printing opacity characteristic, the black layer covers the first region between each pixel unit of the front of circuit base plate, the second region between each LED chip in each pixel unit, and the black layer that the ejecting plain noodles of each LED chip covered, improve the contrast of LED display module and the display screen that adopts this LED display module, promote the display effect; because the black molecular layer is formed by the molecule sputtering deposition of the black substrate, the consistency of the black molecular layer is high, the chromaticity difference of each area can be reduced, and the display effect is further improved.

Description

LED display module and LED display screen

Technical Field

The utility model relates to a show the field, especially relate to a LED display module assembly and LED display screen.

Background

COB (Chip On Board) LED (Light-Emitting Diode) and COG (Chip On Glass) LED display are used as an active Light-Emitting display technology, and have the advantages of high brightness and wide color gamut. Under the condition that the maximum brightness is limited, the minimum brightness of the LED screen is reduced, and the key for improving the contrast is realized.

In order to improve the contrast, referring to fig. 1, a black layer 101 is disposed on a circuit substrate used by a conventional LED display panel, and a pad on the circuit substrate is exposed from the black layer 101 for subsequent soldering of an LED chip 102. The black layer is generally a black ink layer or a black glue layer in the processes of printing, coating, etc. Due to the flatness of the circuit substrate and the defects of the existing printing, coating and other processes, the thickness of the black layer 101 is uneven, and further, the chromaticity difference of the black layer 101 is large.

In addition, with the decrease of the pixel pitch, the display area ratio occupied by the LED chip 102 in the COB LED display screen is larger and larger, and due to the limitation of the process of the circuit substrate, the size of the pad on the circuit substrate for soldering the electrode of the LED chip 102 is difficult to match with the size of the electrode of the LED chip 102. Generally, after the LED chip 102 is soldered on the circuit substrate by solder paste, the solder paste used becomes silver after melting and covers the surface of the pad, as shown in 1011 in fig. 1, and the silver has a reflective characteristic, which results in that the LED display screen is not black enough when the screen is black, i.e. the contrast of the display screen is reduced, and the display effect is affected.

Therefore, how to solve the problem that the contrast of the display screen is reduced due to the large chromaticity difference of the black layer on the existing circuit substrate and the silver solder paste covering the surface of the bonding pad is a technical problem which needs to be solved at present.

SUMMERY OF THE UTILITY MODEL

In view of the above-mentioned correlation technique not enough, the utility model aims at providing a LED display module assembly and LED display screen aims at solving the big and because of the pad surface is covered by silver tin cream of black layer colourity difference on the current circuit substrate, and leads to the problem that the contrast of display screen reduces.

In order to solve the technical problem, the utility model provides a LED display module assembly, include:

a circuit substrate having opposing front and back sides;

the pixel units are arranged on the front surface and comprise at least two LED chips, one surface of each LED chip, which is close to the front surface, is a bottom surface, and the other surface of each LED chip, which is far away from the front surface, is a light ejecting surface;

the LED light source comprises a front surface, a first area, a second area and a black molecular layer, wherein the front surface is arranged in the first area between the pixel units, the front surface is arranged in the second area between the LED chips in the pixel units, the black molecular layer covers the light-emitting surface of each LED chip, and the black molecular layer is a light-transmitting molecular layer formed by sputtering molecules of a black base material and depositing the molecules.

Optionally, the black molecule layer is directly deposited on the front surface and the light-emitting surface, and is directly deposited on the side surface of each of the LED chips to cover the side surface of each of the LED chips.

Optionally, the LED display module further includes a first light-transmitting encapsulation layer disposed on the black molecule layer.

Optionally, the LED display module further includes a second light-transmitting encapsulation layer disposed between the front surface of the circuit substrate and the black molecule layer.

Optionally, the thickness of the black molecular layer is greater than or equal to 2 nanometers and less than or equal to 300 nanometers.

Optionally, the black molecular layer includes at least two molecular sublayers stacked in sequence.

Optionally, the at least two molecular sublayers include at least two of an oxide molecular sublayer, a silicide molecular sublayer, and a nitride molecular sublayer.

Optionally, the light transmittance of the black molecular layer is greater than or equal to 30% and less than or equal to 50%.

Optionally, a difference in thickness of each region of the black molecule layer is not greater than 4nm.

Based on the same inventive concept, the utility model also provides a LED display screen, including drive element and as above LED display module assembly, drive element sets up in the back or the front of circuit substrate, and with each pixel unit electricity is connected.

The utility model provides a LED display module and LED display screen, wherein the front of LED display module's circuit base plate is equipped with a plurality of pixel, still be equipped with the black layer that has printing opacity characteristic, the first region between each pixel of the front of circuit base plate is spent to this black layer, the second region between each LED chip in each pixel (also cover with the pad after LED chip welded on the circuit base plate also promptly), and the black layer that the ejecting plain noodles of each LED chip covered covers, consequently, can make the region on the pad be black and no longer be silver, can improve the contrast of LED display module and the display screen that adopts this LED display module, promote display effect;

in addition, the black molecular layer is a light-transmitting molecular layer formed by depositing the molecules of the black base material which are sputtered onto the first area, the second area and the light-ejecting surfaces of the LED chips, so that the consistency of the black molecular layer formed in each area can be ensured, the chromaticity difference of the black molecular layer can be reduced, and the display effect is further improved.

Drawings

FIG. 1 is a schematic diagram of a display panel in the prior art;

fig. 2 is a schematic structural diagram of a first LED display module according to a first embodiment of the present invention;

fig. 3 is a schematic structural diagram of a LED display module according to a first embodiment of the present invention;

fig. 4 is a schematic structural view of a LED display module according to a first embodiment of the present invention;

fig. 5 is a schematic structural view of a LED display module according to a first embodiment of the present invention;

fig. 6 is a schematic structural diagram of a black molecule layer according to an embodiment of the present invention;

fig. 7 is a schematic diagram of a pixel unit according to a first embodiment of the present invention;

fig. 8 is a schematic structural diagram of a LED display module according to a second embodiment of the present invention;

fig. 9 is a schematic structural view of a second LED display module according to a second embodiment of the present invention;

fig. 10 is a schematic structural view of a LED display module according to an embodiment of the present invention;

fig. 11 is a schematic structural diagram of a LED display module according to the second embodiment of the present invention;

fig. 12 is a schematic structural diagram of a LED display module according to an embodiment of the present invention;

fig. 13 is a schematic structural diagram six of an LED display module according to an embodiment of the present invention;

fig. 14 is a schematic view of a structure of an LED display screen provided by the third embodiment of the present invention.

Detailed Description

In order to facilitate understanding of the present invention, the present invention will be described more fully hereinafter with reference to the accompanying drawings. The preferred embodiments of the present invention are shown in the drawings. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

In the related art, due to the flatness of the circuit substrate and the defects of the existing printing, coating and other processes, the thickness of a black layer formed on the circuit substrate is uneven, and the chromaticity difference is large; and after the LED chip is welded on the circuit substrate through the solder paste, the adopted solder paste can become silver after being melted and cover the surface of the bonding pad, and the silver has a light reflecting characteristic, so that the LED display screen is not black enough when being in a black screen, the contrast ratio is low, and the display effect is poor.

Based on this, the present invention is intended to provide a solution to the above technical problem, the details of which will be explained in the following embodiments.

The first embodiment is as follows:

the present embodiment provides an LED display module with better reliability and contrast, referring to an exemplary LED display module as shown in fig. 2, which includes a circuit substrate 1, a plurality of pixel units 2 and a black molecule layer 3, wherein:

the circuit substrate 1 has opposite front and back surfaces; it should be understood that the circuit substrate 1 in the present embodiment may be made of a rigid material, such as but not limited to phenolic paper laminated board, epoxy paper laminated board, polyester glass felt laminated board, epoxy glass cloth laminated board, BT resin board, and glass board; the circuit board 1 may be made of a flexible material, and for example, but not limited to, a polyester film, a polyimide film, and a fluorinated ethylene propylene film may be used. In some examples, corresponding circuits may be integrated in or on the circuit substrate 1 according to application requirements, and may include, but are not limited to, circuits connected to LED chips, driving circuits, and the like. A plurality of pads (not shown in the figure) on the front surface of the wiring substrate 1; it should be understood that the number of the pads and the arrangement on the front surface of the circuit substrate 1 in the present embodiment can be flexibly set according to the application requirements. For example, a plurality of pads may be disposed, and the plurality of pads may be disposed in an array on the circuit substrate 1, or disposed in a staggered manner between adjacent rows of pads, etc. In some examples of the present embodiment, the material of the bonding pad may be, but is not limited to, copper, silver, gold, etc. In this embodiment, the bonding pads on the front surface of the circuit substrate 1 can be used for, but not limited to, electrical connection with the electrodes of the LED chip.

The pixel units 2 in this embodiment are disposed on the front surface of the circuit substrate 1, it should be understood that the front surface and the back surface of the circuit substrate 1 in this embodiment are relative, the upper surface of the circuit substrate 1 in fig. 2 is the front surface thereof, and the lower surface thereof is the back surface thereof, and in other examples, the lower surface of the circuit substrate 1 may also be the front surface and the upper surface thereof is the back surface. In this embodiment, one pixel unit 2 includes at least two LED chips, and the number and types (including the size, light emitting color, whether the LED chips are mounted, flipped, or vertical) of the LED chips included in each pixel unit 2 may be the same, may also be different, or may be partially the same and partially different, and may be flexibly set according to a specific application scenario. For example, as shown in fig. 7, in some examples, the pixel unit 2 may include three LED chips emitting red light, blue light and green light, respectively, and the red LED chip, the green LED chip and the blue LED chip are sequentially arranged. In other examples, the pixel unit may include a white LED chip, etc. in addition to the red LED chip, the green LED chip, and the blue LED chip, based on the illustration of fig. 7. It should be understood that the specific arrangement of the LED chips 21 in the pixel unit 2 in the present embodiment can be a delta arrangement, a linear arrangement, a central symmetrical arrangement, etc., and the present embodiment is not limited thereto. In terms of size classification, the LED chip adopted in this embodiment may include at least one of a Mini LED chip, a Micro LED chip, and a common LED chip having a size larger than that of the Mini LED chip; the LED chip may include at least one of a flip LED chip, a front-mounted LED chip, and a vertical LED chip in terms of the distribution of the LED chip electrodes.

In this embodiment, the surface of the LED chip disposed on the front surface of the circuit board 1, which is close to the front surface of the circuit board 1, is defined as a bottom surface of the LED chip, and the surface of the LED chip, which is far from the front surface of the circuit board 1, is defined as an ejection light surface of the LED chip. In the present embodiment, a region between the pixel units 2 on the front surface of the wiring substrate 1 is defined as a first region S1, and a region between the LED chips 21 in the pixel units 2 on the front surface of the wiring substrate 1 is defined as a second region S2. Wherein the first region S1 includes a pad between the pixel units 2, and the second region S2 includes a pad between the LED chips 21 in the pixel units 2.

In this embodiment, referring to fig. 2, the LED display module further includes a first region S1 disposed on the front surface of the circuit substrate 1 and locating the front surface of the circuit substrate 1 between the pixel units 2, a second region S2 disposed between the LED chips 21 in the pixel units 2, and a black molecule layer 3 covered by the light-emitting surfaces of the LED chips 21, where the black molecule layer 3 is a light-transmitting molecule layer with light-transmitting property; therefore, the first area S1 and the second area S2 are covered by the black molecular layer 3, so that after the LED chips 21 are welded on the front surface of the circuit substrate 1, the pad surfaces of the circuit substrate 1, which are silver or gray, are also covered by the black molecular layer, which can improve the contrast of the LED display module and the display screen using the LED display module on the basis of satisfying the display condition, and improve the display effect.

In this embodiment, the black molecule layer 3 is a light-transmitting molecule layer having a light-transmitting property, which is formed by sputtering molecules of a black base material onto the first region S1, the second region S2, and the light-emitting surfaces of the LED chips 21. Therefore, the consistency of the black molecular layer 3 formed in each region can be ensured, so that the chromaticity difference of each region of the black molecular layer can be reduced, the thickness of the black molecular layer and the consistency of the chromaticity of each region can be ensured, and the display effect is further improved. It should be understood that, in the present embodiment, the molecules of the black matrix may be sputtered onto the first region S1, the second region S2 and the light-emitting surface of each LED chip 21 to form a light-transmitting molecular layer by, but not limited to, an existing magnetron sputtering process. For example, in one example of an application, but not limited to, application number 202110158644.3, entitled: a black matrix forming method, a display module and a display device are disclosed as the magnetron sputtering process shown in the Chinese invention patent application with the publication number of 2021.06.18. The black base material can be placed on a platform with a magnetic field, the circuit substrate 1 provided with the pixel units 2 (i.e. the front surface of the circuit substrate 1) is placed opposite to the black base material, the front surface of the circuit substrate 1 and the pixel units 2 are opposite to the black base material, then the black base material is bombarded by ions guided by the magnetic field, and molecules (also called particles) of the black base material are uniformly sputtered on the front surface of the circuit substrate 1 and the surfaces of the LED chips 21. Of course, it should be understood that other magnetron sputtering processes may be used to replace the magnetron sputtering process shown in this application example, or other sputtering processes that can sputter molecules of the black matrix onto a designated area to deposit and form a light-transmitting molecular layer may be used, which is not limited in this embodiment and is not described in detail again.

In the example shown in fig. 2, the black molecule layer 3 covers the side surfaces of each LED chip 21 between the bottom surface and the light-emitting surface thereof in addition to the first region S1, the second region S2, and the light-emitting surface of each LED chip 21. That is, the black molecule layer 3 can be directly deposited on the first region S1, the second region S2 and the light-emitting surfaces and the side surfaces of the LED chips 21; moreover, as the black molecular layer 3 is formed by adopting a sputtering process, the black molecular layer 3 can be formed in each area without dead angles, and the coverage rate of the formed black molecular layer 3 on the front surface of the circuit substrate 1 can reach 100%; the flatness of the front surface of the circuit substrate 1 after the LED chip is welded is not required, namely is not limited by the flatness, the flatness of the circuit substrate 1 does not influence the thickness uniformity of the black molecular layer 3, the thickness of the prepared black molecular layer 3 is uniform, namely the thickness difference of each region (namely each position of the black molecular layer 3) of the black molecular layer 3 is not more than 4nm, the formed black molecular layer 3 has good consistency, and the display effect can be further improved; the thickness of the black molecular layer 3 can reach a nanometer level, for example, the thickness of the formed black molecular layer can be controlled to be more than or equal to 2 nanometers and less than or equal to 300 nanometers by controlling the magnetron sputtering time; while ensuring the contrast, the use of black materials can be reduced as much as possible, and the cost is reduced; in addition, the magnetron sputtering process is mature, the efficiency is high, the production flow is simple to control, and the cost is low; the black molecule layer 3 has a certain light transmittance, for example, the light transmittance of the formed black molecule layer 3 can be set to be greater than or equal to 30% and less than or equal to 50%, so that the contrast is ensured, the light loss can be reduced, and the blackness and the light transmittance of the black molecule layer can be considered at the same time.

Referring to fig. 3, another LED display module shown in this embodiment is mainly different from the LED display module shown in fig. 2 in that the black molecule layer 3 does not cover the side surfaces of the LED chips 21. In the production of the LED display module shown in fig. 3, the LED display module shown in fig. 2 may be produced first, and then the black molecule layer 3 covering the side surfaces of the LED chips 21 may be removed. In the process of forming the black molecular layer 3 by the magnetron sputtering process, the side surfaces of the LED chips 21 may be covered by a mask or the like, so as to prevent the black molecular layer 3 from covering the side surfaces of the LED chips 21.

It should be understood that, in the present embodiment, the black molecule layer 3 may be a single-layer structure, and in some application scenarios, the black molecule layer 3 of the single-layer structure may include only one kind of molecule, and in this case, in the magnetron sputtering process, only one kind of black substrate may be used. In other application scenarios, the black molecule layer 3 with a single-layer structure may also include at least two molecules, and at this time, at least two black substrates may be used in the magnetron sputtering process, and the at least two black substrates may be bombarded simultaneously, so that the at least two black substrates are uniformly deposited in the above regions, respectively; in this application scenario, since the black molecule layer 3 includes at least two kinds of molecules, characteristics such as the degree of blackness and the light transmittance of the black molecule layer 3 can be better harmonized to meet application requirements, so that the display effect can be further improved. In yet another application scenario of the present example, the black molecule layer 3 may be a composite layer structure including at least two molecular sublayers, and the molecules included in adjacent sublayers are different; each molecular sublayer may include only one molecule, or may include more than two molecules; in the application scenario, at least two black substrates can be adopted in the magnetron sputtering process, and the at least two black substrates can be bombarded in sequence, for example, a first black substrate can be bombarded to form a first black molecular sublayer within a time period of t1, and then a second black substrate can be bombarded within a time period of t2, so as to form a second black molecular sublayer on the first black molecular sublayer; of course, a third black molecular sublayer, a fourth black molecular sublayer, etc. may be formed on the second black molecular sublayer in sequence as required. It is of course also possible to form the first black molecular sublayer on the second black molecular sublayer and then form the second black molecular sublayer on the first black molecular sublayer, that is, to alternately form the first black molecular sublayer and the second black molecular sublayer. When the black molecule layer 3 is a composite layer structure, the specific structure of the sub-layer can be flexibly set according to the specific application requirements. For example, an exemplary black molecule layer 3 is shown in fig. 6, and includes a first black molecule layer 31, a second black molecule layer 32, and a third black molecule layer 33, which are sequentially formed, and molecules included in adjacent black molecule layers are different; the molecules included in each black molecule sublayer can be flexibly set according to factors such as light transmission and blackness, so that the light transmission and the blackness of the finally formed black molecule layer 3 are blended according to requirements, and the display effect is improved while the contrast is ensured. That is, in this embodiment, on the premise that the OD (Optical Density) value of the black molecule layer 3 reaches the required standard, different light transmittance can be achieved by changing the black matrix material used and the structure or composition of the black molecule layer, and thus, the present invention can be better applied to various application scenarios.

For example, in some application scenarios of the present embodiment, the black matrix used for forming the black molecule layer 3 may include, but is not limited to, an oxide matrix, a silicide matrix, a nitride matrix, and a corresponding composite matrix, wherein the composite matrix may include, but is not limited to, a composite of at least two of an oxide, a silicide, and a nitride. For example, but not limited to AZO substrate, siO ₂ Substrate, siO substrate, siC substrate, si ₃ N ₄ At least one of the substrates. When the black molecule layer 3 is a composite layer structure including at least two molecule sublayers stacked in sequence, the at least two molecule sublayers may include, but are not limited to, at least two of an oxide molecule sublayer, a silicide molecule sublayer, a nitride molecule sublayer, and a composite molecule sublayer. For example, in the example shown in fig. 6, the first black molecule sublayer 31 may be an oxide molecule sublayer, the second black molecule sublayer 32 may be a silicide molecule sublayer, and the third black molecule sublayer 33 may be a nitride molecule sublayer (of course, the number of specifically included sublayers of the black molecule layer 3, and the specific material of each sublayer may be flexibly set). The composition of at least two of the above oxides, silicides and nitrides is conventional, low in cost and good in universality.

In the two LED display modules shown in fig. 2 and fig. 3 of the present embodiment, the two LED display modules may further include a first packaging layer 41 disposed on the black molecule layer 3 and transmitting light, as shown in fig. 4 and fig. 5, respectively. In the first encapsulation layer 41 of the present embodiment, the first encapsulation layer 41 of the present embodiment may be, but is not limited to, a glue layer, which may form a protection layer for the pixel unit 2 and the black molecule layer 3. For example, in some application examples, the first encapsulation layer 41 may be a transparent encapsulation glue layer using a transparent epoxy glue, so as to form a sealing protection for the pixel unit 2 and the black molecule layer 3 on the circuit substrate 1. In some application scenarios, white powder (e.g., including but not limited to SiO) may be added to the transparent epoxy glue on demand ₂ Powder), melanin, lightAt least one of the particles (such as fluorescent powder, quantum dots and the like) is converted, so that the light emitting effect of the LED display module is further adjusted. In addition, in the embodiment, the upper surface of the first encapsulation layer 41 (that is, the surface of the first encapsulation layer 41 away from the front surface of the circuit substrate 1) may be set to be a matte surface, a bright surface, a frosted surface, a matte surface, etc. as required, so as to achieve different appearance effects.

Example two:

in this embodiment, another exemplary LED display module is provided, as shown in fig. 8, a plurality of pixel units 2 are disposed on the front surface of the circuit substrate 1, the second encapsulation layer 42 directly covers the front surface of the circuit substrate 1, and the second encapsulation layer 42 also covers the areas between the LED chips 21 in the pixel units 2; the black molecule layer 3 of the LED display module in this embodiment is attached to the second encapsulation layer 42, that is, the LED display module in this embodiment further includes the second encapsulation layer 42 which is disposed between the front surface of the circuit substrate 1 and the black molecule layer 3 and is transparent. As can be seen from fig. 8, the black molecule layer 3 in this embodiment also covers the first region S1 between the pixel units 2 on the circuit substrate 1, the second region S2 between the LED chips in the pixel units 2, and the light-emitting surfaces of the LED chips. The first region S1 and the second region S2 in this embodiment are defined in the same way as the first region S1 and the second region S2 in the above embodiment, so that the black molecule layer 3 visually covers the front surface of the circuit board 1 by 100%, and the black molecule layer 3 has light transmittance, so that the contrast and the display effect of the LED display module are improved on the basis of ensuring the display condition of the LED display module.

It should be understood that the second encapsulation layer 42 in the present embodiment may employ, but is not limited to, a glue layer. The second encapsulation layer 42 may form a protection for the pixel cell 2. For example, in some application examples, the second encapsulation layer 42 may also be a transparent encapsulation glue layer using, but not limited to, a transparent epoxy glue, so as to form a hermetic protection for the pixel unit 2 on the circuit substrate 1. In some application scenarios, white powder (for example, including but not limited to SiO) can be added into the transparent epoxy glue according to the requirement ₂ Powder), melanin, light conversion particles (e.g. of the typePhosphor, quantum dots, etc.) to further adjust the light-emitting effect of the LED display module. In addition, in the embodiment, the upper surface of the second encapsulation layer 42 (i.e., the surface of the first encapsulation layer 41 away from the front surface of the circuit substrate 1) may also be set to be a matte surface, a bright surface, a frosted surface, a matte surface, etc. as required, so as to achieve different appearance effects.

In the LED display module shown in fig. 8 in this embodiment, the thickness of the second packaging layer 42 is greater than the height of the LED chip 21, so that the second packaging layer 42 covers the light-emitting surface of the LED chip 21. In other examples of the present embodiment, the thickness of the second encapsulation layer 42 may also be set to be less than or equal to the height of the LED chip 21, so that the light emitting surface of each LED chip 21 is exposed out of the second encapsulation layer 42 and covered by the black molecule layer 3. For example, referring to fig. 9, in this example, the thickness of the second encapsulation layer 42 is equal to the height of the LED chip 21, and the light-emitting surface of the LED chip 21 is in direct contact with the black molecule layer 3 and is covered by the black molecule layer 3. Referring to fig. 10 as another example, in this example, the thickness of the second encapsulation layer 42 is smaller than the height of the LED chip 21, the light-emitting surface of the LED chip 21 is in direct contact with the black molecule layer 3 and is covered by the black molecule layer 3, and the region of the LED chip 21 exposed from the second encapsulation layer 42 is also in direct contact with the black molecule layer and is covered by the black molecule layer 3. As can be seen from the above examples, the structure of the second encapsulation layer 42 and the structure of the black molecule layer covering the second encapsulation layer 42 in the present embodiment can be flexibly changed to meet the requirements of various application scenarios.

In some application examples of the embodiment, in order to avoid crosstalk between adjacent pixel units 2, a light blocking member 5 that does not transmit light may be disposed between the adjacent pixel units 2 on the front surface of the circuit substrate 1 according to requirements, so as to further improve the display effect. The light blocking member 5 in this embodiment may be, but is not limited to, a black glue layer which is opaque to light.

In another example of application of this embodiment, referring to fig. 12, in order to further improve reliability, a third encapsulation layer 43 may be further disposed on the black molecule layer 3, and the black molecule layer 3 may be protected by the third encapsulation layer 43. The third encapsulation layer 43 in this example can adopt but is not limited to the material and structure of the first encapsulation layer 41 shown in the above embodiment, and will not be described herein again. It should be understood that the materials of the third encapsulating layer 43 and the second encapsulating layer 42 in this example may be the same or different, and the embodiment does not limit the same.

It should be understood that, in this embodiment, the material, structure, light transmittance, and blackness of the black molecule layer 3 may be, but not limited to, the material and structure of the black molecule layer 3 shown in the above embodiment, and details thereof are not described again in this embodiment. The sputtering process used in the formation of the black molecule layer 3 in this embodiment may also adopt, but is not limited to, the sputtering process shown in the above embodiment, and the difference is only that the molecules of the black matrix in this embodiment are directly sputtered onto the second encapsulation layer 42, or directly sputtered onto the surfaces of the second encapsulation layer 42 and the LED chip 21, which is not described again in this embodiment.

In still other application examples of the present embodiment, referring to fig. 13, the LED display module structure may also be a structure provided with two black molecule layers 3, wherein one black molecule layer 3 may be, but is not limited to, the black molecule layer 3 shown in the first embodiment, which is directly attached to the front surface of the circuit substrate 1 and the surface of the LED chip 21, and another black molecule layer 3 is directly attached to the second encapsulation layer 42. In the two black molecule layers 3 in this application example, the transmittance of each black molecule layer 3 is higher than that of only one black molecule layer 3 in the previous examples, for example, the transmittance of each black molecule layer 3 in fig. 13 can be set to 60% to 70%, and the transmittance of each single black molecule layer 3 in the previous examples can be set to 30% to 50%, so that on the basis of meeting the overall transmittance requirement, the black contrast and the reliability of the product are improved.

Example three:

the embodiment provides an LED display screen, which includes at least one LED display module in each of the above embodiments, that is, the LED display screen in this embodiment is an LED direct display type display screen, and further includes a driving element, where the driving element is disposed on a back surface or a front surface of a circuit substrate of the LED display module, and is electrically connected to each pixel unit. It should be understood that the driving element in the present embodiment may adopt an AM (Active Matrix) Active driving manner or a PM (Passive Matrix) Passive driving manner to drive the LED display module. And the LED display screen provided by the embodiment can be widely applied to electronic equipment with display screens, such as mobile phones, notebook computers, tablet computers, intelligent wearable eye protection products, vehicle-mounted terminals, advertisement display terminals and the like.

For easy understanding, in the present embodiment, the LED display panel is described by taking the LED display module shown in fig. 4 as an example, and referring to fig. 14, the driving element 6 of the LED display panel is disposed on the back surface of the circuit substrate 1 and electrically connected to each pixel unit 2 on the front surface of the circuit substrate 1 to drive the LED chip 21 in each pixel unit 2. In some application scenarios of the present example, other electronic components besides the LED chip 21 may be flexibly disposed on the front surface and/or the back surface of the circuit substrate 1, and the disposed electronic components may include, but are not limited to, resistors, capacitors, and the like, and may be specifically selected according to application requirements.

In the present example, the electrodes of the LED chip 21 of each pixel unit 2 may be electrically connected to the corresponding pads on the front surface of the wiring board 1 using, but not limited to, solder paste. The solder paste may be, but not limited to, a lead-containing solder alloy such as a tin-lead (Sn-Pb) based alloy, a tin-lead-bismuth (Sn-Pb-Bi) based alloy, or a tin-lead-silver (Sn-Pb-Ag) based alloy; lead-free solder alloys, such as tin-silver (Sn-Ag) alloys, tin-bismuth (Sn-Bi) alloys, tin-zinc (Sn-Zn) alloys, tin-antimony (Sn-Sb), tin-silver-copper (Sn-Ag-Cu) alloys, and tin-bismuth-silver (Sn-Bi-Ag) alloys, can also be used. And it should be understood that the solder paste in this embodiment may be replaced with conductive paste equally as required, for example, but not limited to, conductive silver paste.

The black molecule layer 3 in this embodiment covers at least the first region S1 between the pixel units 2 on the front surface of the circuit substrate 1 and the second region S2 between the LED chips 21 in the pixel units 2, so that it can be ensured that after the LED chips 21 are soldered to the corresponding pads on the front surface of the circuit substrate 1, the black molecule layer 3 which is black is covered on the surface of the pad, and is silver-colored compared with the surface of the existing soldering tin paste covered on the surface of the pad, in this embodiment, the optical characteristics of the black molecule layer 3 can be used to absorb the incident light, thereby preventing the pad from reflecting light due to the silver-colored surface, and improving the contrast. And the black molecular layer 3 has the light transmission performance at the same time, so that at least part of the light emitted by each LED chip 21 can be transmitted out of the black molecular layer 3, and the display is realized. The front surface of the circuit substrate 1 is set to be black without additional modes such as spraying a black ink layer, so that the manufacturing process can be simplified, the manufacturing cost can be reduced, and the thickness of the display screen can be reduced due to the omission of the black ink layer.

In some examples of the present embodiment, the LED display screen may further include a transparent protective film covering the first encapsulation layer 41 (when the LED display module shown in fig. 8-11 is used, the transparent protective film is disposed on the black molecule layer 3). The protective performance of the LED display module can be further improved by the transparent protective film. The thickness of the transparent protection film in the present embodiment can also be flexibly set according to the requirement, for example, but not limited to, 10 μm to 300 μm. The transparent protective film in the example can be a double-core layer structure consisting of at least two sub-adhesive layers, and can also be a single-layer structure; and the transparent protective film can adopt but not limited to a transparent adhesive layer or a plastic sheet, etc.

In some application examples of the embodiment, in order to implement color display, one pixel unit in the LED display module may be configured to support emission of red light, green light, and blue light, so in this example, at least a portion of the plurality of LED chips 21 included in the pixel unit may emit red light, at least a portion of green light, and a portion of blue light. For example, as shown in fig. 7, the LED chips 21 may include, but are not limited to, blue LED chips, red LED chips, green LED chips. In some application scenarios, the blue LED chip and the green LED chip may be gallium nitride-based LED chips, and the red LED chip may be gallium arsenide-based LED chips. In other examples, all the LED chips 21 in the pixel unit 2 may be replaced by blue LED chips, and in order to allow a part of the LED chips to emit green light and red light, respectively, corresponding light conversion layers may be disposed on the light emitting surfaces of the blue LED chips. It should be understood that the above describes only the case where one pixel supports the emission of three colors of red, green, and blue, but in some examples, the LED chip 21 of one pixel unit 2 may emit at least one of cyan, white, and yellow light in addition to the emission of three colors of red, green, and blue.

It can be seen that, according to the LED display module and the display screen provided in this embodiment, a black molecule layer can be formed by using an existing sputtering process (for example, a magnetron sputtering process) to cover the front surface of the circuit substrate between the pixel units and the LED chips in the pixel units (including the areas where the LED chips are welded to the pads on the front surface of the circuit substrate), and the black molecule layer has a light-transmitting property, so that light loss can be reduced as much as possible under the condition that display conditions are satisfied, and the black molecule layer is formed by molecules, and the formed black molecule layer can be covered without a dead angle, so that the coverage rate of the black molecule layer on the front surface of the circuit substrate can reach 100%, and thus the contrast of the display screen can be better improved; the thickness of the formed black molecular layer is uniform and can be controlled at a nanometer level, the consistency is good, the thicknesses of the LED display module and the display screen can be reduced, and the ultra-thinning is facilitated; the adopted existing sputtering process is mature, the production flow is simple to control, the universality is good, the yield is high, and the cost is low.

In addition, the front surface of the circuit substrate is not required to be additionally set to be black by spraying a black ink layer and the like, so that the manufacturing process can be simplified, the manufacturing cost can be reduced, and the thickness of the display panel can be further reduced by omitting the black ink layer.

Meanwhile, an encapsulation layer (e.g., the first encapsulation layer or the third encapsulation layer or the transparent protective film of the above example) having a light transmission property may be further disposed on the black molecule layer, so that the display performance of the COB LED may be optimized and the protection effect may be improved. Therefore, the LED display module and the LED display screen provided by the embodiment have high contrast, low COB LED light transmittance loss and high protectiveness.

It is to be understood that the invention is not limited to the above-described embodiments, and that modifications and variations may be made by those skilled in the art in light of the above teachings, and all such modifications and variations are intended to be included within the scope of the invention as defined in the appended claims.

Claims

1. The utility model provides a LED display module assembly which characterized in that includes:

a circuit substrate having opposing front and back faces;

the pixel units are arranged on the front face and comprise at least two LED chips, one face, close to the front face, of each LED chip is a bottom face, and one face, far away from the front face, of each LED chip is an ejection polished face;

2. The LED display module of claim 1 wherein the layer of black molecules is deposited directly on the front and top facets and directly on the sides of each of the LED chips to cover the sides of each of the LED chips.

3. The LED display module of claim 2, wherein the LED display module further comprises a first encapsulant layer disposed over the layer of black molecules and transmissive to light.

4. The LED display module of claim 1, further comprising a light transmissive second encapsulant layer disposed between the front surface of the circuit substrate and the layer of black molecules.

5. The LED display module of any of claims 1-4, wherein the layer of black molecules has a thickness of 2 nm or more and 300 nm or less.

6. The LED display module of any of claims 1-4, wherein the layer of black molecules comprises at least two molecular layers stacked in sequence.

7. The LED display module of claim 6, wherein the at least two molecular sublayers comprise at least two of an oxide molecular sublayer, a silicide molecular sublayer, and a nitride molecular sublayer.

8. The LED display module of any of claims 1-4, wherein the light transmittance of the layer of black molecules is greater than or equal to 30% and less than or equal to 50%.

9. The LED display module of any of claims 1-4, wherein the difference in thickness of each region of the layer of black molecules is no greater than 4nm.

10. An LED display screen, comprising a driving element and the LED display module according to any one of claims 1 to 9, wherein the driving element is disposed on the back surface or the front surface of the circuit substrate and electrically connected to each pixel unit.