Mini LED backlight source test method based on FCT test equipment

Abstract

The invention discloses a Mini LED backlight source testing method based on FCT testing equipment, relates to the field of backlight source testing, and solves the problem that backlight source testing efficiency is low at the present stage. The method comprises the steps that optical performance testing is conducted on a Mini LED screen, and a brightness abnormal signal or a color abnormal signal of the Mini LED screen is generated; randomly sampling and selecting a plurality of lamp beads in the Mini LED screen, marking the lamp beads as light-emitting diodes to be tested, connecting the plurality of light-emitting diodes to be tested to obtain a light-emitting diode group to be tested, and fixing the light-emitting diode group to an FCT test machine; performing electrical parameter testing on the to-be-tested light-emitting diode group to generate a power supply abnormal signal or a short circuit abnormal signal of the to-be-tested light-emitting diode group; and displaying a brightness abnormal signal, a color abnormal signal, a power supply abnormal signal and a short circuit abnormal signal of the Mini LED screen. According to the invention, the Mini LED backlight source is efficiently and accurately tested.

Description

Technical Field

[0001] The present invention belongs to the technical field of backlight testing, and specifically relates to a Mini LED backlight testing method based on an FCT testing device. Background Art

[0002] Mini LED is an upgraded version of LED technology and a new type of LED display technology, full name Mini Light-Emitting Diode. Its core technology lies in reducing the size of LED chips to between 50 - 200 microns and achieving finer backlight control through high-density arrangement; by detecting optical performance and defects, combined with automated equipment and industry standards, the high picture quality, high reliability, and market compliance of Mini LED can be ensured. With technological progress, the detection efficiency and accuracy will be further improved, promoting the popularization and application of Mini LED technology.

[0003] However, at the current stage, when detecting a Mini LED screen, each Mini LED is usually detected in sequence, without selecting a Mini LED screen for optical performance verification and combining Mini LED lamp beads for electrical parameter testing, resulting in low detection efficiency and extremely high detection costs. Therefore, the present invention proposes a Mini LED backlight testing method based on an FCT testing device. Summary of the Invention

[0004] The purpose of the present invention is to propose a Mini LED backlight testing method based on an FCT testing device to solve the problems raised in the above background art.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions: A Mini LED backlight testing method based on an FCT testing device, the method includes: Step S1, fixing the Mini LED screen to the FCT testing machine platform Step S2, performing an optical performance test on the Mini LED screen to generate a brightness anomaly signal or a color anomaly signal of the Mini LED screen; Step S3, randomly sampling and selecting multiple lamp beads in the Mini LED screen and recording them as the to-be-tested light-emitting diodes, connecting the multiple to-be-tested light-emitting diodes to obtain a to-be-tested light-emitting diode group and fixing it to the FCT testing machine platform; Step S4, performing an electrical parameter test on the to-be-tested light-emitting diode group to generate a power supply anomaly signal or a short-circuit anomaly signal of the to-be-tested light-emitting diode group; Step S5, display the brightness anomaly signal, color anomaly signal, power supply anomaly signal, and short - circuit anomaly signal of the Mini LED screen.

[0006] Further, the optical performance test includes a brightness test and a chromaticity test; the electrical parameter test includes a power supply parameter test and a short - circuit test.

[0007] Further, the test process of the brightness test is specifically as follows: Step S201, send a white display signal to the Mini LED screen, and the Mini LED screen receives the white display signal and switches to the white display mode; Step S202, the Mini LED screen performs brightness tests in sequence from brightness test level 1 to brightness test level Z; where Z is a positive integer, and different brightness levels correspond to white window displays of different range sizes; Step S203, record the brightness values at the centers of the white window displays corresponding to different brightness test levels, which are denoted as the brightness values of the corresponding brightness test levels; select the largest brightness value among all brightness test levels and denote it as the peak brightness of the Mini LED screen; Step S204, after the brightness test level Z is continuously displayed for a fixed duration, divide the Mini LED display screen into K display partitions, and record the real - time brightness values of different pixel points in each display partition; where the fixed duration is greater than or equal to one minute, and K is a positive integer.

[0008] Further, the test process of the brightness test also includes: Step S205, add up the real - time brightness values of all pixel points in the same display partition and take the average as the partition brightness value of the corresponding display partition; obtain the brightness uniformity rate of the Mini LED screen by dividing the smallest partition brightness value among all display partitions by the largest partition brightness value and multiplying by 100%; Step S206, compare the peak brightness with the peak brightness threshold, and compare the brightness uniformity rate with the brightness uniformity threshold. If the peak brightness is greater than or equal to the peak brightness threshold and the brightness uniformity rate is greater than or equal to the brightness uniformity threshold, it is determined that the brightness display of the Mini LED screen is normal; if the peak brightness is less than the peak brightness threshold or the brightness uniformity rate is less than the brightness uniformity threshold, it is determined that the brightness display of the Mini LED screen is abnormal, and a brightness anomaly signal is generated.

[0009] Further, the test process of the chromaticity test is specifically as follows: Step S211, send a standard color display signal to the Mini LED screen, and the Mini LED screen switches to the standard color display mode; where the standard color display mode is used to display multiple colors; Step S212: Divide the Mini LED display screen into multiple display partitions, and randomly select a pixel point in each display partition as a color test point; Step S213: Input a full - red display signal, a full - green display signal, and a full - blue display signal into the Mini LED screen in sequence. Record the chromaticity coordinate value of the first color test point when the full - red display signal is input as RZ1 (RX, RY), record the chromaticity coordinate value of the first color test point when the full - green display signal is input as GZ1 (GX, GY), and record the chromaticity coordinate value of the first color test point when the full - blue display signal is input as BZ1 (BX, BY); Step S214: Calculate the area MJ1 of the color gamut triangle corresponding to the color test point through the formula. The specific calculation formula is as follows: 。

[0010] Furthermore, the test process of the chromaticity test also includes: Step S215: Measure the chromaticity coordinate values of the remaining color test points, and calculate the area of the color gamut triangle of the remaining color test points to obtain MJ2 to MJK; Step S216: Select the minimum value among MJ1 to MJK as the area of the color gamut triangle of the Mini LED screen; divide the area of the color gamut triangle of the Mini LED screen by the area of the standard color gamut to obtain the color gamut coverage rate of the Mini LED screen; Step S217: Compare the color gamut coverage rate with the color gamut coverage rate threshold. If the color gamut coverage rate is greater than or equal to the color gamut coverage rate threshold, it is determined that the Mini LED color test is normal; if the color gamut coverage rate is less than the color gamut coverage rate threshold, it is determined that the Mini LED color display is abnormal, and a color abnormality signal is generated.

[0011] Furthermore, the test process of the power supply parameter test is specifically as follows: Step S401: Connect the light - emitting diode group to be tested to a programmable power supply, apply a rated voltage to the light - emitting diode group to be tested through the programmable power supply of the FCT machine, and set the limit protection current of the light - emitting diode group to be tested; Step S402: If the real - time current value of the light - emitting diode group to be tested is greater than or equal to the limit protection current, the programmable power supply will disconnect the connection with the light - emitting diode group to be tested; if the real - time current value of the light - emitting diode group to be tested is less than the limit protection current, then perform the subsequent steps; Step S403: Send a control instruction to make the light - emitting diode group to be tested enter the maximum brightness mode, and collect the real - time current value and real - time voltage value of the light - emitting diode group to be tested through a data acquisition card.

[0012] Furthermore, the test process of the power supply parameter test also includes: Step S404: Obtain the rated electric power by multiplying the rated current by the rated voltage, and obtain the actual electric power by multiplying the real-time current value by the real-time voltage value; take the absolute value of the difference between the rated electric power and the actual electric power to obtain the electric power deviation value. Step S405: Compare the electric power deviation value with the electric power deviation threshold. If the electric power deviation value is less than the electric power deviation threshold, it is determined that the power supply parameters of the LED to be tested are normal; if the electric power deviation value is greater than or equal to the electric power deviation threshold, it is determined that the power supply test of the LED to be tested is abnormal, and a power supply abnormal signal is generated.

[0013] Furthermore, the specific process of the short-circuit test is as follows: Step S411: Disconnect the connection between the programmable power supply and the LED group to be tested; if there are parallel branches in the LED group to be tested, isolate other branches by physical disconnection means, and select any one branch as the target circuit; if there are no parallel branches in the LED group to be tested, record the circuit corresponding to the LED group to be tested as the target circuit. Step S412: Select the current application end and the voltage application end, and sequentially connect the probes of the current application end and the voltage application end to the positive and negative poles of the target circuit.

[0014] Furthermore, the test process of the short-circuit test further includes: Step S413: Measure the measured resistance value across the target circuit using a resistance measuring device; read the standard resistance value of each LED to be tested in the target circuit, and sum up the standard resistance values of all the LEDs to be tested to obtain the calculated resistance value of the target circuit. Step S414: Obtain the resistance deviation value by subtracting the calculated resistance value from the measured resistance value, and compare the resistance deviation value with the estimated line impedance. If the resistance deviation value is greater than or equal to the estimated line impedance, it is determined that there is an abnormality in the short-circuit test of the target circuit, and a short-circuit abnormal signal is generated; if the resistance deviation value is less than the estimated line impedance, no operation is performed.

[0015] In summary, due to the adoption of the above technical solutions, the beneficial effects of the present invention are as follows: 1. The present invention first fixes the Mini LED screen to the FCT test machine, and then performs an optical performance test on the Mini LED screen to generate a brightness abnormal signal or a color abnormal signal of the Mini LED screen; the present invention realizes the optical performance test of the Mini LED screen. 2. In the present invention, multiple lamp beads are randomly sampled from the Mini LED screen and denoted as the light-emitting diodes to be tested. The multiple light-emitting diodes to be tested are connected to obtain a group of light-emitting diodes to be tested and fixed to the FCT test machine. Then, electrical parameter tests are performed on the group of light-emitting diodes to be tested to generate a power supply abnormal signal or a short-circuit abnormal signal for the group of light-emitting diodes to be tested. Finally, the brightness abnormal signal, color abnormal signal, power supply abnormal signal, and short-circuit abnormal signal of the Mini LED screen are displayed, and the present invention realizes efficient detection of the Mini LED backlight source. Description of the Drawings

[0016] For the convenience of those skilled in the art to understand, the present invention will be further described below in conjunction with the drawings.

[0017] Figure 1 It is a flowchart of the method of the present invention; Figure 2 It is a schematic diagram of the color gamut triangle in the present invention; Figure 3 It is a schematic diagram of the structure of the computer device in the present invention. Detailed Embodiments

[0018] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0019] Embodiment 1, please refer to Figure 1 and Figure 2 As shown, the technical solution provided by the present invention is: a Mini LED backlight source test method based on an FCT test device. First, the optical performance of the entire Mini LED screen is tested to judge the optical abnormal conditions of the Mini LED. Then, the electrical parameters of the lamp beads in the Mini LED screen are detected, and then the electrical abnormal conditions of the Mini LED screen are judged. Finally, the electrical abnormal conditions and optical abnormal conditions of the Mini LED screen are combined and displayed; It should be noted that the Mini LED screen refers to a layer structure in a Mini LED display, specifically a light-emitting layer composed of Mini LEDs; Among them, the FCT test device is a functional circuit test device. Mini LED, also known as sub-millimeter light-emitting diode, refers to an LED chip with a grain size of about 100 microns, and its size is between small-pitch LEDs and Micro-LEDs; In this embodiment, the Mini LED backlight source test method is specifically as follows: Step S1, fix the Mini LED screen to the FCT test machine. Specifically, the FCT test machine integrates a programmable power supply, a data acquisition card, a probe matrix, a photometer, etc., and is used to test the electrical parameters and optical performance of the light-emitting diode group to be tested. Step S2, perform an optical performance test on the Mini LED screen to generate a brightness anomaly signal or a color anomaly signal of the Mini LED screen; among them, the optical performance test includes a brightness test and a chromaticity test. In this embodiment, the brightness test is specifically as follows. Step S201, send a white display signal to the Mini LED screen, and the Mini LED screen receives the white display signal and switches to the white display mode; the white display mode can only present white, and the RGB value of the white display is (255, 255, 255). Step S202, the Mini LED screen sequentially performs brightness tests according to brightness test levels 1 to brightness test level Z; where Z is a positive integer, and different brightness levels correspond to white window displays of different size ranges. Exemplarily, brightness test level 1 corresponds to a P1×P1 white window display, brightness test level 2 corresponds to a P2×P2 white window display, and so on, brightness test level Z corresponds to a Pt×Pt white window display, where P1 < P2 <... < Pt. Step S203, record the brightness values at the centers of the white window displays corresponding to different brightness test levels, and denote them as the brightness values corresponding to the brightness test levels; select the largest brightness value among all brightness test levels and denote it as the peak brightness of the Mini LED screen. Step S204, after the brightness test level Z continuously displays for a fixed duration, divide the Mini LED display screen into K display partitions, and record the real-time brightness values of different pixel points in each display partition; where the fixed duration is greater than or equal to one minute, and K is a positive integer; optionally, K is 9, 16 or 25. Step S205, add up the real-time brightness values of all pixel points in the same display partition and take the average value as the partition brightness value of the corresponding display partition; obtain the brightness uniformity rate of the Mini LED screen by dividing the smallest partition brightness value among all display partitions by the largest partition brightness value and multiplying by 100%. Step S206: Compare the peak brightness with the peak brightness threshold and compare the brightness uniformity rate with the brightness uniformity threshold. If the peak brightness is greater than or equal to the peak brightness threshold and the brightness uniformity rate is greater than or equal to the brightness uniformity threshold, it is determined that the brightness display of the Mini LED screen is normal; if the peak brightness is less than the peak brightness threshold or the brightness uniformity rate is less than the brightness uniformity threshold, it is determined that the brightness display of the Mini LED screen is abnormal, and a brightness abnormal signal is generated. In this embodiment, the chromaticity test is specifically as follows: Step S211: Send a standard color display signal to the Mini LED screen, and the Mini LED screen switches to the standard color display mode; among them, the standard color display mode is used to display multiple colors. Step S212: Divide the Mini LED display screen into multiple display partitions, and randomly select a pixel point in each display partition as the color test point. Step S213: Sequentially input a full red display signal, a full green display signal, and a full blue display signal to the Mini LED screen, and record the chromaticity coordinate value of the first color test point as RZ1 (RX, RY) when the full red display signal is input, record the chromaticity coordinate value of the first color test point as GZ1 (GX, GY) when the full green display signal is input, and record the chromaticity coordinate value of the first color test point as BZ1 (BX, BY) when the full blue display signal is input. Among them, the chromaticity coordinate value, that is, the color coordinate, is a commonly used color coordinate, divided into the horizontal axis X and the vertical axis Y, and is measured by a spectrophotometer. Step S214: Calculate the area MJ1 of the gamut triangle corresponding to the color test point through the formula, and the specific calculation formula is as follows: ; Step S215: Similarly, measure the chromaticity coordinate values of the remaining color test points, and calculate the area of the gamut triangle of the remaining color test points to obtain MJ2 to MJK. Step S216: Please refer to Figure 2, where there are three different specifications of standard gamut areas; select the minimum value among MJ1 to MJK as the area of the gamut triangle of the Mini LED screen; divide the area of the gamut triangle of the Mini LED screen by the standard gamut area to obtain the gamut coverage rate of the Mini LED screen. Step S217: Compare the gamut coverage rate with the gamut coverage rate threshold. If the gamut coverage rate is greater than or equal to the gamut coverage rate threshold, it is determined that the Mini LED color test is normal; if the gamut coverage rate is less than the gamut coverage rate threshold, it is determined that the Mini LED color display is abnormal, and a color abnormal signal is generated.

[0020] Step S3, randomly sample multiple lamp beads in the Mini LED screen and record them as the light-emitting diodes to be tested. Connect the multiple light-emitting diodes to be tested to obtain a group of light-emitting diodes to be tested and fix them to the FCT test bench; Among them, the connection methods are series and parallel.

[0021] Step S4, perform electrical parameter tests on the group of light-emitting diodes to be tested to generate a power supply abnormal signal or a short-circuit abnormal signal for the group of light-emitting diodes to be tested; the electrical parameter tests include power supply parameter tests and short-circuit tests; In this embodiment, the power supply parameter test is specifically as follows; Step S401, connect the group of light-emitting diodes to be tested to a programmable power supply, apply a rated voltage to the group of light-emitting diodes to be tested through the programmable power supply of the FCT bench, and set the limiting protection current of the group of light-emitting diodes to be tested; Specifically, if the group of light-emitting diodes to be tested includes a total of 20 light-emitting diodes to be tested, every four light-emitting diodes to be tested are connected in series as the same branch, and five branches are connected in parallel in the FCT bench; and the specifications of each light-emitting diode to be tested are the same, the rated voltage is 3 volts, and the rated current is 100 milliamperes; then the total rated voltage of the circuit is the rated voltage of each branch: 4×3 = 12 volts, and the total rated current of the circuit is the rated current of five branches connected in parallel: 5×100 = 500 milliamperes; it should be noted that the above data are only provided for convenience of explanation and calculation, and there will be deviations in magnitude during actual operation; Therefore, apply a rated voltage of 12 volts between the VCC pin and the GND pin of the group of light-emitting diodes to be tested; when setting the limiting protection current, optionally, set it to 1.5 times the rated current corresponding to the light-emitting diode to be tested, that is, 750 milliamperes; Step S402, if the real-time current value of the group of light-emitting diodes to be tested is greater than or equal to the limiting protection current, the programmable power supply will disconnect the connection with the group of light-emitting diodes to be tested; if the real-time current value of the group of light-emitting diodes to be tested is less than the limiting protection current, then perform the subsequent steps; Step S403, send a control instruction to make the group of light-emitting diodes to be tested enter the maximum brightness mode, and collect the real-time current value and real-time voltage value of the group of light-emitting diodes to be tested through a data acquisition card; Step S404, obtain the rated electric power by multiplying the rated current by the rated voltage, and obtain the actual electric power by multiplying the real-time current value by the real-time voltage value; take the absolute value of the difference between the rated electric power and the actual electric power to obtain the electric power deviation value; Step S405, compare the electric power deviation value with the electric power deviation threshold. If the electric power deviation value is less than the electric power deviation threshold, it is determined that the power supply parameters of the light-emitting diodes to be tested are normal; if the electric power deviation value is greater than or equal to the electric power deviation threshold, it is determined that the power supply test of the light-emitting diodes to be tested is abnormal, and a power supply abnormal signal is generated; In this embodiment, the short - circuit test is specifically as follows: Step S411: Disconnect the connection between the programmable power supply and the light - emitting diode group to be tested. If there are parallel branches in the light - emitting diode group to be tested, isolate other branches by physical disconnection means, and select any one branch as the target circuit. If there are no parallel branches in the light - emitting diode group to be tested, record the circuit corresponding to the light - emitting diode group to be tested as the target circuit; Step S412: Select the current application terminal and the voltage application terminal, and sequentially connect the probes of the current application terminal and the voltage application terminal to the positive and negative poles of the target circuit; It should be specifically noted that the probe needs to directly contact the metal pad, avoid touching the package of the target light - emitting diode, and the connection of the positive and negative poles needs to be correct. Since the light - emitting diode to be tested is unidirectional conduction, incorrect connection of the positive and negative poles will result in an infinite measured resistance. The current applied by the current application terminal should be less than the conduction current of the light - emitting diode to be tested to avoid lighting the light - emitting diode to be tested; Step S413: Measure the measured resistance value across the target circuit through a resistance measurement device; read the standard resistance value of each light - emitting diode to be tested in the target circuit, and sum up all the standard resistance values of the light - emitting diodes to be tested to obtain the calculated resistance value of the target circuit; Step S414: Obtain the resistance deviation value by subtracting the calculated resistance value from the measured resistance value, and compare the resistance deviation value with the estimated line impedance. If the resistance deviation value is greater than or equal to the estimated line impedance, it is determined that there is an abnormality in the short - circuit test of the target circuit, and a short - circuit abnormality signal is generated. If the resistance deviation value is less than the estimated line impedance, no operation is performed; Among them, the estimated line impedance is determined by the length, cross - sectional area, and material of the line in the target circuit. Specifically, in the calculation, it is obtained by multiplying the resistivity of the corresponding material by the line length and dividing by the cross - sectional area.

[0022] Step S5: Display the brightness abnormality signal, color abnormality signal, power supply abnormality signal, and short - circuit abnormality signal of the Mini LED screen.

[0023] In this application, if there are corresponding calculation formulas, the above - mentioned calculation formulas are all dimensionless and take their numerical values for calculation. Coefficients such as weight coefficients and proportionality coefficients in the formulas are set to obtain a result value by quantifying each parameter. Regarding the magnitudes of the weight coefficient and the proportionality coefficient, as long as they do not affect the proportional relationship between the parameters and the result value, it is acceptable.

[0024] Embodiment 2 Figure 3A structural schematic diagram of a computer device, the computer device may include: a processor, a communications interface, a memory, and a communication bus. Among them, the processor, the communication interface, and the memory complete mutual communication through the communication bus. The processor can call the logical instructions in the memory to execute the Mini LED backlight test method based on the FCT test device. The method includes: fixing the Mini LED screen to the FCT test machine; performing an optical performance test on the Mini LED screen to generate a brightness anomaly signal or a color anomaly signal of the Mini LED screen; randomly sampling multiple lamp beads in the Mini LED screen and recording them as the light-emitting diodes to be tested, connecting the multiple light-emitting diodes to be tested to obtain a group of light-emitting diodes to be tested and fixing them to the FCT test machine; performing an electrical parameter test on the group of light-emitting diodes to be tested to generate a power supply anomaly signal or a short-circuit anomaly signal of the group of light-emitting diodes to be tested; displaying the brightness anomaly signal, the color anomaly signal, the power supply anomaly signal, and the short-circuit anomaly signal of the MiniLED screen.

[0025] In addition, when the logical instructions in the above-mentioned memory can be implemented in the form of software function units and sold or used as an independent product, they can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of this application. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical discs that can store program codes.

[0026] On the other hand, the present application also provides a computer program product, which includes a computer program stored on a computer-readable storage medium. The computer program includes program instructions. When the program instructions are executed by a computer, the computer can execute the Mini LED backlight test method based on the FCT test equipment provided by the above-mentioned various methods. The method includes: fixing the Mini LED screen to the FCT test machine; performing an optical performance test on the Mini LED screen to generate a brightness anomaly signal or a color anomaly signal of the Mini LED screen; randomly sampling and selecting multiple lamp beads in the Mini LED screen and recording them as the light-emitting diodes to be tested, connecting the multiple light-emitting diodes to be tested to obtain a group of light-emitting diodes to be tested and fixing them to the FCT test machine; performing an electrical parameter test on the group of light-emitting diodes to be tested to generate a power supply anomaly signal or a short-circuit anomaly signal of the group of light-emitting diodes to be tested; and displaying the brightness anomaly signal, the color anomaly signal, the power supply anomaly signal, and the short-circuit anomaly signal of the Mini LED screen.

[0027] In another aspect, the present application also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it is configured to execute the Mini LED backlight test method based on the FCT test equipment provided by the above-mentioned various methods. The method includes: fixing the Mini LED screen to the FCT test machine; performing an optical performance test on the Mini LED screen to generate a brightness anomaly signal or a color anomaly signal of the Mini LED screen; randomly sampling and selecting multiple lamp beads in the Mini LED screen and recording them as the light-emitting diodes to be tested, connecting the multiple light-emitting diodes to be tested to obtain a group of light-emitting diodes to be tested and fixing them to the FCT test machine; performing an electrical parameter test on the group of light-emitting diodes to be tested to generate a power supply anomaly signal or a short-circuit anomaly signal of the group of light-emitting diodes to be tested; and displaying the brightness anomaly signal, the color anomaly signal, the power supply anomaly signal, and the short-circuit anomaly signal of the Mini LED screen.

[0028] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place, or may be distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art can understand and implement it without creative efforts.

[0029] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on such an understanding, the above technical solution, in essence, or the part that contributes to the prior art can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0030] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of each embodiment of the present application.

Claims

1. A Mini LED backlight source testing method based on FCT testing equipment, characterized in that: Methods include: Step S1, fixing the Mini LED screen to the FCT test machine; Step S2, performing an optical performance test on the Mini LED screen to generate a brightness abnormality signal or a color abnormality signal of the Mini LED screen; Step S3, randomly sampling and selecting a plurality of lamp beads in the Mini LED screen as light-emitting diodes to be tested, connecting the plurality of light-emitting diodes to be tested to obtain a light-emitting diode group to be tested and fixing the group to the FCT test machine; Step S4, performing an electrical parameter test on the light emitting diode group to be tested, and generating a power supply abnormality signal or a short circuit abnormality signal of the light emitting diode group to be tested; Step S5, displaying the brightness abnormality signal, color abnormality signal, power supply abnormality signal and short circuit abnormality signal of the Mini LED screen.

2. The Mini LED backlight source testing method based on the FCT testing device according to claim 1, characterized in that: The optical performance test includes a brightness test and a chromaticity test; the electrical parameter test includes a power supply parameter test and a short circuit test.

3. The Mini LED backlight source testing method based on the FCT testing device according to claim 2, characterized in that: The test process of the brightness test is as follows: Step S201, sending a white display signal to the Mini LED screen, and the Mini LED screen receives the white display signal and switches to a white display mode; Step S202, the Mini LED screen performs brightness tests in sequence from brightness test level 1 to brightness test level Z; wherein Z is a positive integer, and different brightness levels correspond to white window displays of different sizes; Step S203, recording the brightness values ​​of the white window display center corresponding to different brightness test levels, and recording them as the brightness values ​​of the corresponding brightness test levels; selecting the maximum brightness value among all brightness test levels and recording them as the peak brightness of the Mini LED screen; Step S204, after the brightness test level Z is continuously displayed for a fixed time, the Mini LED display screen is divided into K display partitions, and the real-time brightness values ​​of different pixels in each display partition are recorded; wherein the fixed time is greater than or equal to one minute, and K is a positive integer.

4. The Mini LED backlight source testing method based on the FCT testing device according to claim 3 is characterized in that: The test process of the brightness test also includes: Step S205, adding the real-time brightness values ​​of all pixels in the same display partition and taking the average value as the partition brightness value of the corresponding display partition; the brightness uniformity of the Mini LED screen is obtained by dividing the minimum partition brightness value of all display partitions by the maximum partition brightness value and multiplying by 100; Step S206, compare the peak brightness with the peak brightness threshold, and compare the brightness uniformity with the brightness uniformity threshold. If the peak brightness is greater than or equal to the peak brightness threshold and the brightness uniformity is greater than or equal to the brightness uniformity threshold, the brightness display of the Mini LED screen is deemed to be normal; if the peak brightness is less than the peak brightness threshold or the brightness uniformity is less than the brightness uniformity threshold, the brightness display of the Mini LED screen is deemed to be abnormal, and a brightness abnormality signal is generated.

5. The Mini LED backlight source testing method based on the FCT testing device according to claim 2, characterized in that: The testing process of the chromaticity test is as follows: Step S211, sending a standard color display signal to the Mini LED screen, and the Mini LED screen switches to a standard color display mode; wherein the standard color display mode is used to display multiple colors; Step S212, dividing the Mini LED display screen into a plurality of display partitions, and randomly selecting a pixel point in each display partition as a color test point; Step S213, sequentially inputting a full red display signal, a full green display signal, and a full blue display signal to the Mini LED screen, recording the chromaticity coordinate value of the first color test point when the full red display signal is input as RZ1 (RX, RY), recording the chromaticity coordinate value of the first color test point when the full green display signal is input as GZ1 (GX, GY), and recording the chromaticity coordinate value of the first color test point when the full blue display signal is input as BZ1 (BX, BY); Step S214, the color gamut triangle area MJ1 corresponding to the color test point is calculated by a formula, and the calculation formula is as follows: 。 6. The Mini LED backlight source testing method based on the FCT testing device according to claim 4, characterized in that: The testing process of the chromaticity test also includes: Step S215, measuring the chromaticity coordinate values ​​of the remaining color test points, and calculating the color gamut triangle areas of the remaining color test points to obtain MJ2 to MJK; Step S216, selecting the minimum value among MJ1 to MJK as the color gamut triangle area of ​​the Mini LED screen; and obtaining the color gamut coverage of the Mini LED screen by dividing the color gamut triangle area of ​​the Mini LED screen by the standard color gamut area; Step S217, the color gamut coverage is compared with the color gamut coverage threshold. If the color gamut coverage is greater than or equal to the color gamut coverage threshold, the Mini LED color test is considered normal; if the color gamut coverage is less than the color gamut coverage threshold, the Mini LED color display is considered abnormal and a color abnormality signal is generated.

7. The Mini LED backlight source testing method based on the FCT testing device according to claim 2, characterized in that: The test process of the power supply parameter test is as follows: Step S401, connecting the light emitting diode group to be tested to a programmable power supply, applying a rated voltage to the light emitting diode group to be tested through the programmable power supply of the FCT machine, and setting a limiting protection current of the light emitting diode group to be tested; Step S402, if the real-time current value of the light emitting diode group to be tested is greater than or equal to the limiting protection current, the programmable power supply will be disconnected from the light emitting diode group to be tested; If the real-time current value of the light-emitting diode group to be tested is less than the limiting protection current, the subsequent steps are executed; Step S403, sending a control instruction to make the light emitting diode group to be tested enter the maximum brightness mode, and collecting the real-time current value and real-time voltage value of the light emitting diode group to be tested through the data acquisition card.

8. The Mini LED backlight source testing method based on the FCT testing device according to claim 7, characterized in that: The test process of the power supply parameter test also includes: Step S404, the rated electric power is obtained by multiplying the rated current by the rated voltage, and the actual electric power is obtained by multiplying the real-time current value by the real-time voltage value; the rated electric power is subtracted from the actual electric power and the absolute value is taken to obtain the electric power deviation value; Step S405, compare the electric power deviation value with the electric power deviation threshold. If the electric power deviation value is less than the electric power deviation threshold, it is determined that the power supply parameters of the light-emitting diode to be tested are normal; if the electric power deviation value is greater than or equal to the electric power deviation threshold, it is determined that the power supply test of the light-emitting diode to be tested is abnormal, and a power supply abnormality signal is generated.

9. The Mini LED backlight source testing method based on the FCT testing device according to claim 2, characterized in that: The test process of the short circuit test is as follows: Step S411, disconnecting the connection between the programmable power supply and the light emitting diode group to be tested; if the light emitting diode group to be tested has parallel branches, isolating other branches by means of physical disconnection, and selecting any branch as the target circuit; If the light emitting diode group to be tested does not have a parallel branch, the circuit corresponding to the light emitting diode group to be tested is recorded as the target circuit; Step S412, selecting a current applying end and a voltage applying end, and connecting the probes of the current applying end and the voltage applying end to the positive and negative electrodes of the target circuit in sequence.

10. The Mini LED backlight source testing method based on the FCT testing device according to claim 9, characterized in that: The testing process of the short circuit test also includes: Step S413, measuring the measured resistance values ​​at both ends of the target circuit by a resistance measuring device; reading the standard resistance value of each light emitting diode to be measured in the target circuit, and adding the standard resistance values ​​of all the light emitting diodes to be measured to obtain the calculated resistance value of the target circuit; Step S414, obtain the resistance deviation value by subtracting the calculated resistance value from the measured resistance value, and compare the resistance deviation value with the estimated line impedance. If the resistance deviation value is greater than or equal to the estimated line impedance, it is determined that there is a short circuit test abnormality in the target circuit, and a short circuit abnormality signal is generated; if the resistance deviation value is greater than or equal to the estimated line impedance, no operation is performed.

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