LED backlight module, display screen, and LED backlight module detection method

Abstract

The present invention relates to the field of display technology, and in particular to an LED backlight module, a display screen, and an LED backlight module detection method. The LED backlight module includes a substrate and a plurality of LED chips arranged on the substrate, and is characterized in that: a first detection group is provided for every N LED chips connected in series on the substrate, wherein N≥0, and the first detection group includes a first positive detection point and a first negative detection point, and the first positive detection point and the first negative detection point are respectively connected to the positive and negative poles of the LED chip. By setting detection points on each LED chip or on a plurality of LED chips connected in series at intervals, each LED chip or each group of LED chips connected in series can be lit up and detected before the LED chip is packaged, which greatly improves the accuracy of the detection, thereby improving the yield of the product.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to an LED backlight module, a display screen including the LED backlight module, and a method for detecting the LED backlight module. Background Art

[0002] The development of LCD TV backlight modules has evolved from early CCFL (Cold Cathode Fluorescent Lamp) to current direct-type LED backlight modules or edge-type LED backlight modules. The requirements for improving the display effect of LCD (liquid crystal display) are getting higher and higher, and with the development of regional dynamic dimming technology, the energy consumption of LED backlight modules is getting lower and lower. If the number of partitions corresponding to the LED backlight module is smaller, the light and dark contrast presented will be higher, thus realizing HDR.

[0003] Dynamic regional dimming technology is more inclined to direct-type LED backlight modules, which divide the area and perform independent circuit control. At present, the traditional direct-type LED backlight module packaging method is: first mount the backlight beads on the backlight PCB, and then install the lens, install the lightbar (LED backlight bar) and the diffusion plate side by side in order to obtain a uniformly mixed white light. This packaging method has many steps and a complicated process. The thickness of the backlight is limited by the superposition of factors such as the thickness of the device, the height of the lens, and the thickness of the PCB, resulting in LCDs with direct backlights being relatively thick.

[0004] With the development of science and technology, Mini LED backlight modules have been designed. Since the Mini LED backlight module can directly package the chip on the PCB, the thickness of the entire backlight module can be made thinner (OD below 5mm). In addition, due to the small chip size of MiniLED (the general chip width is about 100μm), more partitions can be divided, and even point-to-point control lighting can be achieved, thereby achieving finer partitions and higher light-dark contrast. The HDR effect presented is comparable to OLED, and since it can achieve finer regional dimming, the corresponding energy consumption is greatly reduced.

[0005] However, the current Mini LED backlight module still has the following problems: 1. The brightness of the light emitted from the front of the Mini LED chip is high. To achieve a smaller mixed light distance, the chips need to be arranged more densely. The increase in the number of chips will increase manufacturing costs and reduce the product yield; 2. When the number of partitions is large, more series-parallel circuits are required. If the chip partitions are not fine enough, it is easy to cause uneven brightness between areas. In severe cases, even the brightness in the same area is uneven; 3. If a small partition has bad pixels before or after packaging, detection and repair are also difficult to solve. Summary of the invention

[0006] The embodiments of the present invention provide an LED backlight module, a display screen and an LED backlight module detection method to solve the above technical problems.

[0007] In a first aspect, an LED backlight module is provided, comprising a substrate and a plurality of LED chips arranged on the substrate, wherein a first detection group is arranged for every N LED chips connected in series on the substrate, wherein N≥0, and the first detection group comprises a first positive detection point and a first negative detection point, and the first positive detection point and the first negative detection point are respectively connected to the positive and negative poles of the LED chip.

[0008] By setting detection points on each LED chip or on several intervals of LED chips, each LED chip or each group of LED chips connected in series can be lit up and tested before the LED chips are packaged, which greatly improves the accuracy of the detection and thus improves the yield of the product.

[0009] In a possible implementation of the present invention, several partitions are provided on the substrate, and several LED chips are provided in series or parallel in each partition. The LED backlight module also includes a second detection group capable of independently detecting each partition, and the second detection group includes a second positive detection point and a second negative detection point, and the second positive detection point and the second negative detection point are respectively connected to the positive and negative poles of the partitions.

[0010] In a possible implementation manner of the present invention, the number of the partitions is M, and the total number of the second positive pole detection points and the second negative pole detection points is at least M+1.

[0011] In a possible implementation manner of the present invention, a side surface of the substrate on which the LED chip is disposed is a first side surface, and the first detection group is disposed on the first side surface.

[0012] In a possible embodiment of the present invention, the substrate has a first side surface and a second side surface that are arranged opposite to each other, the LED chip is arranged on the first side surface, the first detection group is arranged on the second side surface, a through hole is opened through the substrate, a conductive member is arranged in the through hole, and the conductive member is respectively connected to the first detection group and the LED chip.

[0013] In a possible embodiment of the present invention, a positive electrode pad, a negative electrode pad and a conductive circuit connecting adjacent positive electrode pads and negative electrode pads are provided on the substrate corresponding to each LED chip, the first positive electrode detection point is provided on the conductive circuit connected to the positive electrode pad, and the first negative electrode detection point is connected to the conductive circuit connected to the negative electrode pad.

[0014] In a possible embodiment of the present invention, the substrate is provided with a side surface of the LED chip as a first side surface, the first side surface is coated with an insulating reflective layer, and the reflective layer is provided with a hollow area for exposing the first positive pole detection point, the first negative pole detection point and the solder pad of the LED chip.

[0015] In a possible implementation manner of the present invention, the reflective layer is a high temperature resistant white ink layer, and the light reflectivity of the white ink layer is greater than 80%.

[0016] In a possible implementation manner of the present invention, a first protective layer is provided on the first positive electrode detection point and the first negative electrode detection point; and / or,

[0017] A second protection layer is provided on the pad.

[0018] In a possible implementation manner of the present invention, the first protective layer and the second protective layer are made of the same material.

[0019] In a possible implementation manner of the present invention, both the first protective layer and the second protective layer are OSP films or metal plating layers.

[0020] In a possible implementation manner of the present invention, the light emission angle of the chip is greater than 120°.

[0021] In a possible embodiment of the present invention, the wavelength span of several of the chips is within 2.5 nm; and / or,

[0022] The voltage drop span of several of the chips is within 0.1V; and / or,

[0023] The optical power span of several of the chips is within 0.2 mW.

[0024] In a possible implementation manner of the present invention, the LED chip is encapsulated on the substrate by an encapsulation colloid.

[0025] In a possible implementation manner of the present invention, a groove is provided on the surface of the packaging colloid, and the groove is not connected to the cavity of the packaging colloid that encapsulates the LED chip.

[0026] In a possible implementation manner of the present invention, the encapsulation colloid is any one of transparent encapsulation glue, YAG phosphor glue, KSF fluoride phosphor or quantum dot protective film.

[0027] In a possible implementation manner of the present invention, a side surface of the substrate facing away from the LED chip is a second side surface, and a heat dissipation layer is provided on the second side surface.

[0028] In a possible implementation manner of the present invention, the heat dissipation layer is a mesh-shaped heat dissipation copper layer.

[0029] In a second aspect, a display screen is provided, comprising the LED backlight module.

[0030] In a third aspect, a method for detecting an LED backlight module is provided, comprising the following steps:

[0031] The detection tool is connected to at least one second detection group on the LED backlight module to light up all LED chips in a specified partition of the LED backlight module, and the partition has a corresponding brightness value after being lit. The brightness value is used to determine that all the LED chips in the partition are qualified when it exceeds a preset brightness value, and to determine that there are unqualified LED chips in the partition when it does not exceed the preset brightness value;

[0032] If there are unqualified LED chips in the partition, the detection tool is connected to the first detection group in the partition, and the LED chips in the partition are lit one by one to determine the position of the unqualified LED chip.

[0033] In a possible implementation manner of the present invention, the detection tool lights up the partitions on the LED backlight module one by one, or the detection tool lights up all the partitions on the LED backlight module at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the drawings required for use in the embodiments or related technical descriptions are briefly introduced below. Obviously, the drawings in the following description are only simplified schematic diagrams of some embodiments of the present invention or related technologies. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0035] Figure 1 Schematic diagram of a top view of an LED backlight module according to an embodiment of the present invention (the first positive electrode detection point and the second positive electrode detection point are on the front side of the substrate).

[0036] Figure 2 for Figure 1 A partial cross-sectional view of .

[0037] Figure 3 for Figure 1 Bottom view of .

[0038] Figure 4 It is a cross-sectional schematic diagram of an LED backlight module according to an embodiment of the present invention (the first positive electrode detection point and the second positive electrode detection point are on the back side of the substrate).

[0039] Figure 5 for Figure 4 Bottom view of the embodiment (heat dissipation layer not shown).

[0040] Figure 6 FIG. 4 is a schematic top view of a packaging colloid according to an embodiment of the present invention.

[0041] Figure 7 FIG. 4 is a schematic side view of a packaging colloid according to an embodiment of the present invention.

[0042] Figure 8 FIG. 4 is a three-dimensional schematic diagram of a packaging colloid according to an embodiment of the present invention.

[0043] In the figure:

[0044] 1. Substrate; 11. Heat dissipation layer; 12. Insulation layer; 13. Conductive circuit; 2. First positive electrode detection point; 3. First negative electrode detection point; 4. Positive electrode pad; 5. Negative electrode pad; 6. White ink layer; 7. Packaging colloid; 71. Groove; 8. LED chip. DETAILED DESCRIPTION

[0045] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] In the description of the embodiments of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0047] In the embodiments of the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0048] Figure 1It is a top view schematic diagram of the LED backlight module according to an embodiment of the present invention (the first positive electrode detection point 2 and the first negative electrode detection point 3 are on the front side of the substrate 1); Figure 2 It is a partial cross-sectional schematic diagram of the LED backlight module of the embodiment of the present invention (the first positive electrode detection point 2 and the first negative electrode detection point 3 are on the front side of the substrate 1). Figure 1 and 2 As shown, an embodiment of the present invention provides an LED backlight module, including a substrate 1 and a plurality of LED chips 8 arranged on the substrate 1, wherein a first detection group is provided for every N LED chips 8 connected in series on the substrate 1, wherein N ≥ 0, and the first detection group includes a first positive detection point 2 and a first negative detection point 3, and the first positive detection point 2 and the first negative detection point 3 are respectively connected to the positive and negative electrodes of the LED chip 8. By providing detection points on each LED chip 8 or on several intervals of LED chips 8, each LED chip 8 or each group of LED chips 8 connected in series can be lit up and detected before the LED chip 8 is packaged, which greatly improves the accuracy of the detection, thereby improving the yield of the product.

[0049] Specifically, the substrate 1 includes an insulating layer 12 and a conductive circuit 13 disposed on the insulating layer 12 and used for connecting the LED chip 8 .

[0050] The substrate 1 can be made of a material with high thermal conductivity, low expansion and high temperature resistance, such as white BT material, FR or aluminum substrate.

[0051] FR4 is an epoxy glass cloth laminate, which is a type of substrate with epoxy resin as adhesive and electronic grade glass cloth as reinforcement material. FR4's bonding sheet and inner core thin copper clad laminate are important substrates for making multi-layer printed circuit boards. The main technical features of FR4 are: stable electrical insulation performance, good flatness, smooth surface, no pits, standard thickness tolerance, low light absorption, suitable for products with high-performance electronic insulation requirements. BT material is a white core material, and its light absorption rate is lower than that of FR4 yellow core material. Usually, the light absorption rate of FR4 is 2-5% higher than that of BT material, so the reflection effect of BT material is very good.

[0052] Aluminum substrate is a metal-based copper-clad laminate with good heat dissipation function. Generally, a single-sided board consists of three layers, namely the circuit layer (copper foil), the insulating layer and the metal base layer. There are also double-sided boards designed for high-end products, with the structure of circuit layer, insulating layer, aluminum base, insulating layer and circuit layer. Aluminum substrate has good thermal conductivity, electrical insulation performance and mechanical processing performance. Compared with traditional FR4, aluminum substrate uses the same thickness and the same line width. Aluminum substrate can carry higher current, the withstand voltage of aluminum substrate can reach 4500V, and the thermal conductivity coefficient is greater than 1.0.

[0053] Specifically, the side of the substrate 1 on which the LED chip 8 is welded is the first side, and the side opposite to the first side is the second side, that is, the first side is the front side of the substrate 1, and the second side is the back side of the substrate 1. Several LED chips 8 are arranged at equal intervals on the first side, and a group of pads are set on the substrate 1 corresponding to each LED chip 8, which are a positive electrode pad 4 and a negative electrode pad 5. The positive electrode pad 4 is connected to the positive electrode of the LED chip 8, and the negative electrode pad 5 is connected to the negative electrode of the LED chip 8. The adjacent positive electrode pads 4 and negative electrode pads 5 are connected through a conductive line 13.

[0054] Furthermore, if Figures 1 to 8 As shown, a conductive circuit 13 is provided on the insulating layer 12 of the substrate 1, and the conductive circuit 13 is a copper wire. The first positive electrode detection point 2 is provided on the conductive circuit 13 and connected to the positive electrode pad 4, and the first negative electrode detection point 3 is provided on the conductive circuit 13 and connected to the negative electrode pad 5. That is, the first detection group is provided on the front side of the substrate 1. This design allows the LED chip 8 to be detected from the front side of the substrate 1, so as to facilitate observation of the lighting of the LED chip 8.

[0055] Of course, the first detection group is not limited to being arranged on the front side of the substrate 1, but can also be arranged on the back side of the substrate 1. Specifically, Figure 3 and Figure 4 As shown, a first detection group is arranged at a position corresponding to the LED chip 8 on the second side surface, and the first positive detection point 2 and the first negative detection point 3 of the first detection group are arranged at intervals. Through holes are respectively opened on the substrate 1 corresponding to the first positive detection point 2 and the first negative detection point 3. The through holes penetrate the substrate 1, and conductive members are arranged in the through holes, which are respectively connected to the first detection group and the corresponding pads of the LED chip 8. By arranging the first detection group on the back of the substrate 1, the arrangement of the corresponding detection points is facilitated, and the influence of the detection points on the light brightness of the LED chip 8 can be eliminated.

[0056] Preferably, the conductive member is a metal conductive layer disposed in the through hole. More preferably, the conductive member is a copper layer disposed in the through hole. The plated conductive layer can reduce the difficulty of manufacturing and installing the conductive member, effectively improve the processing efficiency, and reduce the defective rate of the product.

[0057] In a preferred embodiment of the present invention, a plurality of partitions are provided on the substrate 1, and a plurality of LED chips 8 are provided in series in each partition. The LED backlight module also includes a second detection group capable of independently detecting each partition, and the second detection group includes a second positive detection point and a second negative detection point, and the second positive detection point and the second negative detection point are connected to the positive and negative electrodes of the partitions, respectively. By setting the partitions, the detection difficulty and detection amount of the LED chips 8 on the substrate 1 can be reduced.

[0058] The specific detection steps are as follows:

[0059] Step S100, use the detection tool to first connect the second positive detection point and the second negative detection point of each partition, light up the LED chip 8 in the entire partition, and make a preliminary judgment. If it is judged that the brightness in the partition is normal, then detect the next partition until all partitions on the entire substrate 1 are detected. If it is judged that the brightness in the partition is abnormal, otherwise enter step S200.

[0060] Of course, all the partitions can also be lit at one time. During the operation, it is only necessary to energize the second positive electrode detection point and the second negative electrode detection point on the substrate 1 at the same time.

[0061] Step S200, marking the partitions with brightness problems;

[0062] Step S300, using a detection tool to connect the first positive detection point 2 and the first negative detection point 3 in the partition with a problem, lighting up the LED chips 8 in the partition one by one or lighting up a plurality of continuous and serially connected LED chips 8, and performing another detection. If the brightness of the LED chip 8 is normal, continue to detect other LED chips 8 in the partition until all LED chips 8 in the partition are detected. If the brightness of the LED chip 8 is abnormal or not bright, proceed to step S400;

[0063] Step S400, identifying LED chips 8 with brightness problems;

[0064] Step S500, repair or replace the problematic LED chip 8, then test the LED chip 8, and then proceed to the next assembly process after all LED chips 8 are lit.

[0065] By setting up partitions and setting up a second detection group in each partition, the LED chips 8 on the substrate 1 can be screened on a large scale first, and then the LED chips 8 in each partition can be carefully checked, so as to quickly lock the area of ​​the problematic LED chips 8, greatly reduce the detection amount of LED chips 8, and improve the detection speed.

[0066] Abnormal partition brightness means that the brightness value, voltage drop or wavelength value of the LED chips 8 corresponding to the number of LED chips 8 in the corresponding partition does not meet the requirements.

[0067] In addition, the detection of the LED chip 8 is performed before the LED chip 8 is packaged, which is convenient for the inspection and replacement of the LED chip 8.

[0068] Preferably, the number of partitions is M, and the sum of the number of second positive pole detection points and second negative pole detection points is at least M+1. For example, if there are 4 partitions on the substrate 1, then the sum of the number of second positive pole detection points and second negative pole detection points is 5, and 1 second positive pole detection point and 4 second negative pole detection points can be set on the substrate 1, and the 4 second negative pole detection points are respectively connected to the negative poles of the 4 partitions. Such a design can greatly reduce the number of second positive pole detection points or second negative pole detection points on the substrate 1, thereby reducing the manufacturing cost.

[0069] In another preferred embodiment of the present invention, an insulating reflective layer is coated on the first side of the substrate 1, and a hollow area is provided on the reflective layer for exposing the first positive detection point 2, the first negative detection point 3 and the soldering pad of the LED chip 8. By setting the reflective layer, the reflective layer can reflect more than 80% of the light, thereby effectively uniformizing the brightness between the areas of the LED chip 8 on the substrate 1, avoiding the problem of uneven brightness between areas or within the areas due to the imprecise partitioning of the LED chip 8. In addition, this reflective layer can also effectively reduce the arrangement density of the LED chip 8 on the substrate 1, thereby reducing the manufacturing cost. The hollow area is set to expose the detection points and soldering pads, which is convenient for welding and testing of the LED chip 8.

[0070] Preferably, the reflective layer is a high temperature resistant white ink layer 6, and the light reflectivity of the white ink layer 6 is greater than 80%.

[0071] In a preferred embodiment of the present invention, a first protective layer is provided on the first positive electrode detection point 2 and the first negative electrode detection point 3; and / or, a second protective layer is provided on the pad, and the first protective layer and the second protective layer are made of the same material, both of which are OSP films. The OSP film is an organic film, which can be formed on the surface of the pad or the detection point through the OPS process to protect the copper layer of the pad and the detection point. The OSP film can also prevent oxidation and pollution at high temperatures. The thickness of the OSP film is generally controlled at 0.2-0.5 microns.

[0072] Of course, the first protective layer and the second protective layer can also be selected as metal plating. The metal plating can not only protect the copper layer of the protection pad and the detection point, but also ensure that the front side of the substrate 1 has a higher light output rate. In addition, it can also ensure that the detection point is conductive for easy detection, which makes it easier to weld the pad and the LED chip 8.

[0073] Optionally, the first protective layer and the second protective layer are gold-plated layers or silver-plated layers. The gold-plated layers and the silver-plated layers not only have good electrical conductivity, but also have high light reflectivity.

[0074] Furthermore, the light emitting angle of the LED chip 8 is greater than 120°. The LED chip 8 with a large light emitting angle can be used in conjunction with an LED backlight module that realizes ultra-thin and uniform light mixing. In this embodiment, the LED backlight module is a Mini LED backlight module.

[0075] Optionally, the wavelength span of the plurality of LED chips 8 is within 2nm; and / or, the voltage drop span of the plurality of LED chips 8 is within 0.1V; and / or, the optical power span of the plurality of LED chips 8 is within 0.2mW. The wavelength span refers to the wavelength difference of all LED chips 8 on the substrate 1, the voltage drop span refers to the voltage difference of all LED chips 8 on the substrate 1, and the optical power span refers to the optical power difference of all LED chips 8 on the substrate 1.

[0076] Furthermore, the wavelength of the LED chip 8 is 448.5-450 nm or 450-451.5 nm, the voltage of the LED chip 8 is 2.7-2.75 V, and the optical power of the LED chip 8 is 3.6-3.7 mW.

[0077] In another preferred embodiment of the present invention, the LED chip 8 is packaged on the substrate 1 by the packaging colloid 7. Each LED chip 8 is independently packaged by the packaging colloid 7, which can reduce the internal stress of the LED chip 8 and thus improve the reliability of the LED chip 8.

[0078] like Figures 6 to 8 As shown, in order to reduce the stress of the packaging colloid 7 on the LED chip 8, a groove 71 is provided on the packaging colloid 7, and the groove 71 is not connected to the cavity of the packaging LED chip 8. Preferably, the grooves 71 can also be crisscrossed on the entire packaging colloid 7 to enhance the elimination of stress.

[0079] Optionally, the packaging colloid 7 is a transparent packaging glue, and the packaging glue is epoxy resin or silica gel, which can reduce light loss.

[0080] Alternatively, the encapsulating colloid 7 is any one of yellow phosphor glue, encapsulating glue mixed with high color gamut R and G color KSF powder, or red and green quantum dot protective films, so as to obtain white light.

[0081] The packaging colloid 7 on the surface of the packaged LED chip 8 is rectangular, hemispherical or ellipsoidal.

[0082] In another preferred embodiment of the present invention, referring to Figures 1 to 3As shown, the side of the substrate 1 away from the LED chip 8 is the second side, and the second side is provided with a heat dissipation layer 11. By providing the heat dissipation layer 11 on the back side of the substrate 1, the heat dissipation on the substrate 1 can be accelerated. Since the number of LED chips 8 in the LED backlight module is large, the heat generated is also very large, and the LED chips 8 are highly sensitive to heat, so providing the heat dissipation layer 11 can accelerate the heat dissipation of the LED backlight module and extend the service life of the LED chips 8 of the LED backlight module.

[0083] Preferably, the heat dissipation layer 11 is a dot-shaped heat dissipation copper layer. The dot-shaped heat dissipation copper layer can accelerate the heat dissipation of the substrate 1 and reduce stress, while having low manufacturing cost, and can reserve installation positions for the second detection group or the first detection group while performing all-round uniform heat dissipation on the substrate 1.

[0084] An embodiment of the present invention further provides a display screen, comprising an LED backlight module as described in any of the above embodiments. The structure and function of the LED backlight module are clearly explained in the above embodiments and will not be repeated here.

[0085] In the description of this specification, the description with reference to the terms "an embodiment", "example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0086] The technical principle of the present invention is described above in conjunction with specific embodiments. These descriptions are only for explaining the principle of the present invention and cannot be interpreted as limiting the scope of protection of the present invention in any way. Based on the explanations herein, those skilled in the art can associate other specific implementations of the present invention without paying creative labor, and these methods will fall within the scope of protection of the present invention.

Claims

1. A method for detecting an LED backlight module, wherein the LED backlight module comprises a substrate and a plurality of LED chips arranged on the substrate, wherein a first detection group is provided for every N LED chips connected in series on the substrate, wherein: N≥0, the first detection group includes a first positive detection point and a first negative detection point, the first positive detection point and the first negative detection point are respectively connected to the positive and negative electrodes of the LED chip, and by setting detection points on each LED chip or a plurality of LED chips at intervals, each LED chip or each group of LED chips connected in series can be lit before the LED chip is packaged; The invention is characterized in that: the substrate is provided with a plurality of partitions, each of the partitions is provided with a plurality of the LED chips connected in series or in parallel, the LED backlight module further comprises a second detection group capable of independently detecting each of the partitions, and the LED backlight module detection method comprises the following steps: The detection tool is connected to at least one second detection group on the LED backlight module to light up all the LED chips in a specified partition of the LED backlight module, and the partition has a corresponding brightness value after being lit up. The brightness value is used to determine that all the LED chips in the partition are qualified when it exceeds a preset brightness value, and to determine that there are unqualified LED chips in the partition when it does not exceed the preset brightness value; If there are unqualified LED chips in the partition, the detection tool is connected to the first detection group in the partition, and lights up the LED chips in the partition one by one or lights up multiple continuous and series-connected LED chips to determine the location of the unqualified LED chip.

2. The LED backlight module detection method according to claim 1, characterized in that: The substrate is provided with several partitions, each of which is provided with several LED chips connected in series or in parallel, and the LED backlight module also includes a second detection group capable of independently detecting each of the partitions, the second detection group includes a second positive detection point and a second negative detection point, and the second positive detection point and the second negative detection point are respectively connected to the positive and negative poles of the partitions.

3. The LED backlight module detection method according to claim 2, characterized in that: The number of the partitions is M, and the total number of the second positive pole detection points and the second negative pole detection points is at least M+1.

4. The LED backlight module detection method according to claim 1, characterized in that: A side surface of the substrate on which the LED chip is disposed is a first side surface, and the first detection group is disposed on the first side surface.

5. The LED backlight module detection method according to claim 1, characterized in that: The substrate has a first side surface and a second side surface that are arranged opposite to each other, the LED chip is arranged on the first side surface, the first detection group is arranged on the second side surface, a through hole is opened through the substrate, a conductive member is arranged in the through hole, and the conductive member is respectively connected to the first detection group and the LED chip.

6. The LED backlight module detection method according to any one of claims 1 to 5, characterized in that: A positive electrode pad, a negative electrode pad and a conductive circuit connecting adjacent positive electrode pads and negative electrode pads are arranged on the substrate corresponding to each LED chip, the first positive electrode detection point is arranged on the conductive circuit connected to the positive electrode pad, and the first negative electrode detection point is connected to the conductive circuit connected to the negative electrode pad.

7. The LED backlight module detection method according to any one of claims 1 to 5, characterized in that: The side of the substrate where the LED chip is provided is the first side, the first side is coated with an insulating reflective layer, and the reflective layer is provided with a hollow area for exposing the first positive electrode detection point, the first negative electrode detection point and the solder pad of the LED chip.

8. The LED backlight module detection method according to claim 7, characterized in that: The reflective layer is a high temperature resistant white ink layer, and the light reflectivity of the white ink layer is greater than 80%.

9. The LED backlight module detection method according to claim 7, characterized in that: A first protective layer is provided on the first positive electrode detection point and the first negative electrode detection point; and / or, A second protection layer is provided on the pad.

10. The LED backlight module detection method according to claim 9, characterized in that: The first protection layer and the second protection layer are made of the same material.

11. The LED backlight module detection method according to claim 9 or 10, characterized in that: The first protective layer and the second protective layer are both OSP films or metal plating layers.

12. The LED backlight module detection method according to any one of claims 1 to 5, characterized in that: The light emission angle of the chip is greater than 120°.

13. The LED backlight module detection method according to any one of claims 1 to 5, characterized in that: The wavelength span of several of the chips is within 2.5 nm; and / or, The voltage drop span of several of the chips is within 0.1V; and / or, The optical power span of several of the chips is within 0.2 mW.

14. The LED backlight module detection method according to any one of claims 1 to 5, characterized in that: The LED chip is packaged on the substrate through a packaging colloid.

15. The LED backlight module detection method according to claim 14, characterized in that: A groove is provided on the surface of the packaging colloid, and the groove is not connected with the cavity of the packaging colloid that encapsulates the LED chip.

16. The LED backlight module detection method according to claim 14, characterized in that: The packaging colloid is any one of transparent packaging glue, YAG phosphor glue, KSF fluoride phosphor or quantum dot protective film.

17. The LED backlight module detection method according to any one of claims 1 to 5, characterized in that: A side surface of the substrate facing away from the LED chip is a second side surface, and a heat dissipation layer is disposed on the second side surface.

18. The LED backlight module detection method according to claim 17, characterized in that: The heat dissipation layer is a mesh-shaped heat dissipation copper layer.

19. The LED backlight module detection method according to claim 1, characterized in that: The detection tool lights up the partitions on the LED backlight module one by one or the detection tool lights up all the partitions on the LED backlight module at the same time.

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