LED die bonding virtual imaging display screen
By adopting four light-emitting chips distributed in an isometric array in the LED display screen, the LED flip chip unit and conductive film layer coated substrate layer structure is solved, and the problems of strong graininess of LED small-pitch display screen lamp beads and high PCB board thickness are achieved, achieving high-definition display and cost reduction.
Patent Information
- Application Number
- CN202421928730.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-09
- Publication Date
- 2025-07-18
- Estimated Expiration
- 2034-08-09
AI Technical Summary
The existing LED small-pitch display lamp beads have strong granularity and many grains. The PCB board is too thick, the cost is high, and the design is difficult, making it difficult to achieve small-pitch display and reduce the cost of PCB board.
LED flip chip units are adopted, each chip unit contains four light emitting chips. Through isometric array distribution and conductive film layer covering the substrate layer structure, the effect of flexible film and multi-layer board is achieved, reducing the difficulty of PCB board design, improving pixel density and reducing weight.
Without increasing the number of lamp beads, the pixel density is four times larger, the display effect is clearer, the power demand is halved, the PCB board is thinner, the cost is reduced, the adaptability is improved, and the installation is simplified.
Smart Images
Figure CN223123908U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of LED display screens, and specifically, to an LED die-bonding virtual imaging display screen. Background Art
[0002] In recent years, LED display technology has made remarkable progress in the application field, and its market scale has been continuously expanding. It has now become a key link in the LED industrial chain. In particular, LED transparent display screens have become a research hotspot due to their unique advantages. Small-pitch high-definition LED display screens have been widely used in many industries, such as subways, airports, glass walkways, advertising media, chain stores, large shopping malls, corporate exhibition halls, museums, and science and technology museums. They are mainly used for the display and promotion of commercial advertisements, the rendering of scene atmospheres, and the transmission of information windows.
[0003] However, for existing small-pitch LED display screens, in order to improve pixel quality, the lamp beads have strong granularity and a large number of particles, and the product requires multiple layers of boards to make the PCB circuit, resulting in an overly thick PCB board. This not only increases the cost of the product, making the cost per square meter of the display screen relatively high, but also increases the difficulty of designing the PCB board. To meet the design requirements, it is often necessary to use multi-layer circuit boards, or even high-end PCB boards with high prices, which undoubtedly increases the production cost and makes it more difficult to promote the product.
[0004] Therefore, how to improve the imaging quality of existing small-pitch LED display screens without increasing the number of lamp beads and at the same time reduce the cost of the PCB board has become an urgent technical problem in the industry. Summary of the Utility Model
[0005] In order to overcome the technical problems in the existing technology that the lamp beads of small-pitch LED display screens have strong granularity, a large number of particles, an overly thick PCB board, and high cost, the utility model provides an LED die-bonding virtual imaging display screen.
[0006] The technical solution of the utility model is as follows:
[0007] An LED die-bonding virtual imaging display screen, comprising:
[0008] A PCB layer, including a substrate layer and a conductive thin film layer arranged in a stacked manner, and the driving circuit is etched on the conductive thin film layer;
[0009] An LED flip-chip layer, having a number of LED flip-chip units arranged in an equidistant array. Each LED flip-chip unit has four light-emitting chips, including one red light chip, two green light chips, and one blue light chip, and the two green light chips are arranged diagonally, and the red light chip and the blue light chip are arranged diagonally;
[0010] Within the same flip-chip LED unit or within two or three adjacent flip-chip LED units, any three adjacent light-emitting chips of different colors form a pixel;
[0011] The drive circuit is electrically connected to the flip-chip LED unit.
[0012] By adopting the above technical solution, the flip-chip LED units are distributed in an equidistant array. Each light-emitting chip can not only form a pixel with different-color light-emitting chips within the same flip-chip LED unit, but also form a pixel with adjacent different-color light-emitting chips of the surrounding flip-chip LED units, enabling one pixel of the flip-chip LED virtual imaging display screen to be expanded into 4 virtual pixels. The number of LED pixels increases, the pixel density of the display screen increases, achieving a 4-fold display pixel effect, with a clearer display effect and no increase in the number of lamp beads; achieving a small-pitch display effect by using a flip-chip LED die bonding method with a large pitch, reducing the PCB board design difficulty; in addition, using the structure of a conductive thin film layer covering the substrate layer to achieve the effect of a double-sided board or a multi-layer board, which can not only form a flexible film, but also the PCB board is thinner, greatly reducing the weight of the finished flip-chip LED virtual imaging display screen.
[0013] According to the present invention of the above solution, it is characterized in that two green chips of the same flip-chip LED unit respectively form a pixel with the red light chip and the blue light chip of the flip-chip LED unit where they are located;
[0014] Each green chip also forms a pixel with the red light chip of the flip-chip LED unit where it is located and the blue light chip of an adjacent flip-chip LED unit;
[0015] Each green chip also forms a pixel with the blue light chip of the flip-chip LED unit where it is located and the red light chip of an adjacent flip-chip LED unit;
[0016] Each green chip also forms a pixel with the red light chips and blue light chips on two adjacent flip-chip LED units.
[0017] Preferably, the first distance between two adjacent light-emitting chips on the same flip-chip LED unit is equal to the second distance between two adjacent light-emitting chips on an adjacent flip-chip LED unit.
[0018] According to the present invention of the above solution, it is characterized in that the drive circuit includes a plurality of drive branches, each of the drive branches is provided corresponding to one of the flip-chip LED units, and each of the drive branches is used to drive one of the flip-chip LED units and each light-emitting chip therein.
[0019] Furthermore, the driving branch has multiple driving branches, and the multiple driving branches respectively control different single light-emitting chips.
[0020] Furthermore, in the direction perpendicular to the plane of the PCB layer, the driving branch is vertically aligned with the corresponding LED flip-chip unit in terms of the setting position.
[0021] By adopting the above technical solution, each driving branch independently drives the corresponding LED flip-chip unit, ensuring the consistency of each module, thereby providing the possibility for the flexible application of the display screen. Specifically, during the process of cutting the entire LED die-bonded virtual imaging display screen, the remaining modules after cutting can still maintain a normal working state. Therefore, the display screen can be cut according to the requirements of different usage sites without the need to re-design the layout scheme, significantly improving the adaptability of the display screen, reducing the design and manufacturing costs caused by site changes, and at the same time simplifying the installation and configuration process.
[0022] According to the present utility model of the above solution, it is characterized in that the driving circuits on every two adjacent conductive thin film layers are electrically connected through the through holes on the substrate layer; the driving circuit on the conductive thin film layer adjacent to the LED flip-chip unit is used to drive the light-emitting chip, and the driving circuit on the conductive thin film layer far from the LED flip-chip unit is used to drive the control chip.
[0023] Optionally, the substrate layer is a glass fiber layer made of glass fiber material.
[0024] Optionally, the substrate layer is a transparent thin film layer made of PET transparent material or CPI transparent material, so that the PCB layer can be light-transmissive.
[0025] According to the present utility model of the above solution, it is characterized in that it further includes a transparent adhesive layer, and the transparent adhesive layer is arranged on the surface of the LED die-bonded virtual imaging display screen; the transparent adhesive layer vacuum-seals the LED flip-chip layer, so that the LED flip-chip layer is not easily affected by external rainwater, and effectively protects the light-emitting chips in the LED flip-chip unit from being scratched and avoids dead lights.
[0026] Optionally, the transparent adhesive layer is an optical adhesive.
[0027] According to the present utility model of the above solution, it is characterized in that the LED die-bonded virtual imaging display screen further includes a control chip and a HUB interface, the control chip is electrically connected to the driving circuit, and the control chip is electrically connected to an external device through the HUB interface; wherein, the control chip and the driving circuit are separately arranged, so as to ensure that after the LED die-bonded virtual imaging display screen is cut, it will not affect the normal operation of the control chip to control the cut display screen.
[0028] Optionally, the control chip and the drive circuit are connected to the drive bar through a flexible circuit board.
[0029] For the utility model according to the above solution, its beneficial effects are as follows:
[0030] The LED die-bonding virtual imaging display screen provided by the utility model realizes that one pixel can be expanded into 4 virtual pixels through an equidistant array of LED flip-chip units, and each LED flip-chip unit has four light-emitting chips in an equidistant array. Under the conditions of the same display area and the same number of lamp beads, the pixel pitch is reduced by half and the resolution is increased by four times, that is, the die-bonding method of large-pitch LED flip chips is used to achieve the display effect of small pitch, reduce the design difficulty of the PCB board, and solve the technical problems that it is impossible to achieve small pitch display due to the limitation of traditional LED lamp beads and the difficulty of making high-cost PCB boards;
[0031] Based on this, for a traditional RGB three-color chip array lamp bead display screen, if the driving current of 640,000 pixels requires 800W of power, while the LED die-bonding virtual imaging display screen of the utility model only needs 400W, and 160,000 groups of LED flip-chip units including RGBG 4 light-emitting chips can be driven to achieve the same display effect of 640,000 pixels; it can be seen that under the same pixel display effect, the power requirement is halved;
[0032] Moreover, the utility model uses the structure of a conductive thin film layer covering the substrate layer to achieve the effect of a double-sided board or a multi-layer board, which can not only form a flexible film, but also the PCB board is thinner, greatly reducing the weight of the finished LED die-bonding virtual imaging display screen. Description of the Drawings
[0033] Figure 1 is a schematic structural diagram of the utility model;
[0034] Figure 2 is a schematic layout diagram of the RGBG chips in the LED flip-chip layer;
[0035] Figure 3 is a circuit diagram of the switch tube part in the drive branch circuit;
[0036] Figure 4 is a circuit diagram of the LED lamp bead part;
[0037] Figure 5 is a circuit diagram of the control chip part.
[0038] In the figure,
[0039] 1. Substrate layer; 2. Conductive thin film layer; 3. LED flip-chip layer; 4. LED flip-chip unit; 5. Transparent adhesive layer; 6. Control chip. Detailed Embodiments
[0040] To better understand the purpose, technical solution and technical effect of the present utility model, the following further explains and describes the present utility model in conjunction with the accompanying drawings and embodiments. It should be noted that: similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, it is declared that the embodiments described below are only used to explain the present utility model and are not used to limit the present utility model.
[0041] It should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time.
[0042] The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this application is usually placed during use, or the orientation or positional relationship commonly understood by those skilled in the art, or the orientation or positional relationship in which the product of this application is usually placed during use. It is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to this application.
[0043] The terms "first" and "second" are only used for the purpose of convenient description and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of technical features. The meaning of "a plurality" is two or more, unless otherwise specifically defined.
[0044] As Figure 1 and Figure 2 shown, an LED die bonding virtual imaging display screen includes a PCB layer and an LED flip chip layer 3. The PCB layer includes a substrate layer 1 and a conductive thin film layer 2 stacked. The sandwich between the surface of the PCB layer and the substrate layer 1 is the conductive thin film layer 2. The conductive thin film layer 2 covers the substrate layer 1, and a driving circuit is etched on the conductive thin film layer 2. The driving circuits on every two adjacent conductive thin film layers 2 are electrically connected through the through holes on the substrate layer 1; the driving circuit on the conductive thin film layer 2 adjacent to the LED flip chip unit 4 is used to drive the light-emitting chip, and the driving circuit on the conductive thin film layer 2 farthest from the LED flip chip unit 4 is used to drive the control chip 6.
[0045] Utilizing the structure in which the conductive thin film layer 2 covers the substrate layer 1 to achieve the effect of a double-sided board or a multi-layer board, not only a flexible thin film is formed but also the PCB board is thinner, greatly reducing the weight of the finished LED die bonding virtual imaging display screen.
[0046] In the present utility model, the LED flip-chip layer 3 has a number of LED flip-chip units 4 distributed in an equidistant array. Each LED flip-chip unit 4 has four light-emitting chips: one red light-emitting chip, two green light-emitting chips, and one blue light-emitting chip. The two green light-emitting chips are arranged diagonally, and the red light-emitting chip and the blue light-emitting chip are arranged diagonally. As shown in the LED flip-chip unit 4 in the figure, the upper left corner is a green light-emitting chip, the upper right corner is a red light-emitting chip, the lower right corner is a green light-emitting chip, and the lower left corner is a blue light-emitting chip; the distances from the red light-emitting chip / blue light-emitting chip to the two green light-emitting chips are equal.
[0047] Within the same LED flip-chip unit 4 or among two or three adjacent LED flip-chip units 4, any three adjacent light-emitting chips of different colors, namely red, green, and blue, form a pixel. The LED flip-chip unit 4 is electrically connected to the driving circuit.
[0048] As Figure 2 shown, in this embodiment, the two green chips of the same LED flip-chip unit 4 respectively form a pixel with the red light-emitting chip and the blue light-emitting chip of the LED flip-chip unit 4 where they are located, such as pixel points a1 and a2; each green chip also forms a pixel with the red light-emitting chip of the LED flip-chip unit 4 where it is located and the blue light-emitting chip of the adjacent LED flip-chip unit 4, such as pixel point b1; each green chip also forms a pixel with the blue light-emitting chip of the LED flip-chip unit 4 where it is located and the red light-emitting chip of the adjacent LED flip-chip unit 4, such as pixel point c1; each green chip also forms a pixel with the red light-emitting chips and blue light-emitting chips on two adjacent LED flip-chip units 4, such as pixel point d1. It can be seen from this that each light-emitting chip can not only form a pixel with different-color light-emitting chips within the same LED flip-chip unit 4, but also form a pixel with adjacent different-color light-emitting chips of the surrounding LED flip-chip units 4, enabling one pixel point of the LED die-bonding virtual imaging display screen to be expanded into 4 virtual pixel points, increasing the pixel density of the display screen and achieving a display pixel effect 4 times that of the original, with a clearer display effect.
[0049] The LED flip-chip unit 4 is equivalent to a lamp bead containing four light-emitting chips, namely red, blue, green, and blue. This large-spacing lamp bead structure can achieve the display effect of a traditional small-spacing LED display screen and reduce the difficulty of PCB board design. For example, for an LED display screen with a lamp bead pitch of P2.5mm, the present utility model uses 160,000 groups of four LED flip-chip light-emitting chips die-bonded on the PCB board, and the virtual pixels are expanded to 4 times, resulting in 640,000 pixels, which is equivalent to the real pixel display effect of a traditional P1.25mm pitch. In addition to the P2.5mm pitch specification, it can also be other specifications listed in the following table:
[0050]
[0051] It can be seen that for display screens of any specification, when using a flip-chip light-emitting chip with four chips of red, green, blue, and green to mount the die on PCB boards of different sizes, the display pixels are 4 times that of a traditional RGB arrangement structure display screen with the same number of lamp beads. The display size pitch is reduced by half, achieving a higher definition display effect.
[0052] For a display screen with a P1.25mm pitch, if arranged with traditional RGB lamp beads, 640,000 pixels require a driving current of 800W power. In this LED die-mount virtual imaging display screen solution, only 160,000 groups of LED flip-chip units 4 containing four light-emitting chips of red, green, blue, and green need to be driven, and only 400W is required to achieve the display effect of 640,000 pixels. Therefore, under the same pixel display effect, the power requirement is halved.
[0053] In a preferred embodiment, the first pitch between two adjacent light-emitting chips on the same LED flip-chip unit 4, and the second pitch between two adjacent light-emitting chips on adjacent LED flip-chip units 4 satisfy: the first pitch is equal to the second pitch. For example, in the figure, the first pitch r1 between the upper-left light-emitting chip and the upper-right light-emitting chip of the middle LED flip-chip unit 4, and the second pitch r2 between the upper-left light-emitting chip of the middle LED flip-chip unit 4 and the lower-left light-emitting chip of the upper LED flip-chip unit 4 satisfy: r1 = r2.
[0054] In the present utility model, the driving circuit includes a plurality of driving branches. Each driving branch is provided in one-to-one correspondence with the LED flip-chip unit 4, and each driving branch is used to drive one LED flip-chip unit 4 and each light-emitting chip therein. Further, the driving branch has a plurality of driving sub-branches, and the plurality of driving sub-branches respectively control different single light-emitting chips. The driving branch and the corresponding LED flip-chip unit 4 are vertically aligned in the direction perpendicular to the PCB layer surface, so that each driving branch independently drives the corresponding LED flip-chip unit 4, ensuring the consistency of each module. During the cutting work of the entire LED die-mount virtual imaging display screen, the remaining modules after cutting can still maintain a normal working state. Therefore, the display screen can be cut according to different usage site requirements without re-designing the layout scheme, significantly improving the adaptability of the display screen, reducing the design and manufacturing costs caused by site changes, and at the same time simplifying the installation and configuration process.
[0055] Such as Figure 3As shown, in a specific embodiment, the driving branch includes multiple serially connected MOS transistors Q1, Q2, Q3, …… The conduction condition of the MOS transistor is as follows: for an N-channel MOS transistor, it conducts when UG > US; for a P-channel MOS transistor, it conducts when UG < US. The driving circuit utilizes the constant current characteristic in the saturation region of the MOS transistor and the current negative feedback structure circuit. The adopted solution can effectively reduce the constant current operating voltage and realize the control of the magnitude of the constant current output using an external resistor. The driving current range is from 14.5 mA to 41.5 mA. The driving current can achieve output enable control through an externally connected PWM digital signal, and the control response time is 7 ns. It can be used in LED display screens. By using the independently developed driving circuit, the heat generation of the LED lamp can be greatly reduced, thereby extending the service life of the LED die bonding virtual imaging display screen. In an alternative embodiment, the model of the MOS transistor can be RT5958.
[0056] As Figure 4 shown, for the lamp bead driving and control method of an LED flip chip unit, the nth LED lamp bead in the first row is listed in the figure, and it has four RGBG light-emitting chips. Hi represents the ith row, and n in Rn, 1Gn, 1Bn, 2Gn represents the nth one.
[0057] As Figure 5 shown, the LED die bonding virtual imaging display screen further includes a control chip 6 and a HUB interface. The control chip 6 is electrically connected to the driving circuit. Multiple control chips 6 are divided into multiple groups, with 8 control chips 6 in each group connected in series in sequence. And the same group of control chips 6 controls the light-emitting chips of the same color among several lamp beads. As shown in the figure, the control of the red light chips and green light chips among the first 128 lamp beads is listed. The model of the control chip 6 can be I9929.
[0058] The control chip 6 is electrically connected to an external device through the HUB interface. Among them, the control chip 6 and the driving circuit are separately arranged, so as to ensure that after the LED die bonding virtual imaging display screen is cut, it will not affect the normal operation of the control chip 6 to control the cut display screen. Optionally, the control chip 6 and the driving circuit are connected to the driving strip through a flexible circuit board. When 4 pixels are multiplexed, a high refresh rate IC is adopted, and a HUB board is added to achieve multiple pixels to the greatest extent.
[0059] In the present utility model, the LED die bonding virtual imaging display screen further includes a transparent adhesive layer 5, and the transparent adhesive layer 5 is provided on the surface of the LED die bonding virtual imaging display screen. The transparent adhesive layer 5 vacuum-seals the LED flip chip layer 3, so that the LED flip chip layer 3 is not easily affected by external rainwater, and effectively protects the light-emitting chips in the LED flip chip unit 4 from being scratched and avoids dead lights.
[0060] The transparent adhesive layer 5 is an optical adhesive. The optical adhesive is colorless and transparent, with a light transmittance of more than 95%, good bonding strength, can be cured at room temperature or medium temperature, and has the characteristics of small curing shrinkage, etc.
[0061] In an alternative embodiment, the substrate layer 1 is a glass fiber layer made of glass fiber material.
[0062] In an alternative embodiment, the substrate layer 1 is a transparent thin film layer made of PET transparent material or CPI transparent material, so that the PCB layer can transmit light, so that the substrate layer 1, the conductive thin film layer 2, and the transparent adhesive layer 5 are all in a light-transmitting state, realizing that the finished display screen is "invisible" when not playing, without affecting the light transmission of the display screen.
[0063] The present invention also provides a method for manufacturing an LED die-bonding virtual imaging display screen, including the following steps:
[0064] S1. Obtain a flexible transparent film as the substrate layer;
[0065] The above manufacturing method is realized through a mechanical device. Obtaining the flexible transparent film adhesive can be automatically obtained by a robotic arm or a conveyor belt or other grasping / transportation methods.
[0066] S2. Coating the conductive thin film adhesive on the flexible transparent film;
[0067] The conductive thin film adhesive and the PET layer / CPI layer can be encapsulated together by machine or manually to form a structure coated with the conductive thin film adhesive;
[0068] S3. Etching the conductive thin film to form a driving circuit;
[0069] The user designs the driving circuit in advance. Under reasonable design, the corresponding relationship can be realized, so as to facilitate cutting and splitting. Each driving branch drives each group of LED flip-chip units;
[0070] S4. Electrically connecting the driving circuit and the LED flip-chip unit to form an LED die-bonding virtual display screen.
[0071] In a preferred embodiment, after electrically connecting the driving circuit and the LED flip-chip unit, it further includes:
[0072] S5. Collecting original data;
[0073] The collection of original data is the first step of point-by-point calibration. According to the collection parameters, it can be divided into two types: brightness data and chromaticity data; according to the collection object, it can be divided into module-level collection and full-screen sub-region collection; according to the collection link, it can be divided into in-factory collection before use and on-site collection by users after use;
[0074] S6. Determine the adjustment target value according to the real-time original data;
[0075] S7. Achieve the adjustment of the target value through current amplitude and / or pulse width modulation.
[0076] The LED die bonding virtual imaging display screen uses a uniquely designed film laminating adhesive process, which can achieve true seamless splicing. The entire screen has no dividing lines, with a beautiful, thin and light appearance. The overall appearance is simple and grand, full of a sense of technology. In addition, the LED die bonding virtual imaging display screen of the present utility model has: 1. Ultra-wide viewing angle, and clear display content can be viewed from all angles, and the picture is more impactful; 2. Ultra-quiet, the whole screen adopts a fanless design, with zero noise.
[0077] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.
[0078] The above embodiments only represent several implementation manners of the present utility model, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the utility model patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present utility model, several modifications and improvements can still be made, and these all belong to the protection scope of the present utility model. Therefore, the protection scope of the utility model patent shall be subject to the appended claims.
Claims
1. An LED die bonding virtual imaging display screen, characterized in that, Comprising: A PCB layer, including a base material layer and a conductive thin film layer arranged in a stacked manner, wherein a driving circuit is etched on the conductive thin film layer; An LED flip chip layer, having a number of LED flip chip units distributed in an equidistant array, each of the LED flip chip units having four equidistant light-emitting chips, including one red light chip, two green light chips and one blue light chip, and the two green light chips are arranged diagonally, and the red light chip and the blue light chip are arranged diagonally; Within the same LED flip chip unit or within two or three adjacent LED flip chip units, any three adjacent light-emitting chips of different colors form a pixel point; The driving circuit is electrically connected to the LED flip chip unit.
2. The LED die bonding virtual imaging display screen according to claim 1, wherein Two green chips of the same LED flip chip unit respectively form a pixel point with the red light chip and the blue light chip of the LED flip chip unit where they are located; Each green chip also forms a pixel point with the red light chip of the LED flip chip unit where it is located and the blue light chip of an adjacent LED flip chip unit; Each green chip also forms a pixel point with the blue light chip of the LED flip chip unit where it is located and the red light chip of an adjacent LED flip chip unit; Each green chip also forms a pixel point with the red light chips and the blue light chips on two adjacent LED flip chip units.
3. The LED die bonding virtual imaging display screen according to claim 1, wherein The first distance between two adjacent light-emitting chips on the same LED flip chip unit is equal to the second distance between two adjacent light-emitting chips on an adjacent LED flip chip unit.
4. The LED die-bonding virtual imaging display screen according to claim 1, wherein The driving circuit includes a plurality of driving branches, each of the driving branches is arranged in one-to-one correspondence with the LED flip chip unit, and each of the driving branches is used to drive one of the LED flip chip units.
5. The LED die-bonding virtual imaging display screen according to claim 4, wherein The driving branch has a plurality of driving sub-branches, and the plurality of driving sub-branches respectively control different single light-emitting chips.
6. The LED die-bonding virtual imaging display screen according to claim 4, wherein, In the direction perpendicular to the plane of the PCB layer, the setting positions of the driving branch and the corresponding LED flip chip unit are vertically aligned.
7. The LED die-bonding virtual imaging display screen according to claim 1, wherein, The driving circuits on every two adjacent conductive thin film layers are electrically connected through the through holes on the base material layer; The driving circuit on the conductive thin film layer adjacent to the LED flip chip unit is used to drive the light-emitting chips, and the driving circuit on the conductive thin film layer far from the LED flip chip unit is used to drive the control chips.
8. The LED die-bonding virtual imaging display screen according to claim 1, wherein The base material layer is a glass fiber layer made of glass fiber material.
9. The LED die-bonding virtual imaging display screen according to claim 1, wherein, The base material layer is a transparent thin film layer made of PET transparent material or CPI transparent material, so that the PCB layer can be light-transmissive.
10. The LED die bonding virtual imaging display screen according to claim 1, characterized in that, It further includes a transparent adhesive layer, and the transparent adhesive layer is arranged on the surface of the LED die bonding virtual imaging display screen.