Universal backlight resistor test system and test method

Abstract

The invention discloses a universal backlight resistor test system and test method, and relates to the technical field of electronic test systems. According to the invention, real-time MosBus communication is carried out through upper computer software, hardware control and an acquisition assembly, multiple test requirements are integrated, the corresponding test requirements are quickly met by switching contact states, multiple detections can be completed at one time, and the test efficiency is greatly improved; meanwhile, in the basic detection process, backlight character brightness and chromaticity distribution is analyzed and processed by utilizing a machine vision technology and is integrated with a stability analysis result of the resistor, and a single to-be-tested piece is comprehensively graded, so that the quality of the to-be-tested piece is distinguished according to the score; the detection results of the products are classified more finely, and on the other hand, the position where problems are generated in a centralized mode in production can be found, and a guiding value is generated for production.

Description

Technical Field

[0001] The invention relates to the technical field of electronic testing systems, and in particular to a universal backlight resistance testing system and a testing method. Background Art

[0002] The current test methods for the backlight and resistance of electronic test pieces have problems such as low test efficiency and difficulty in process monitoring. In addition, due to the complexity and diversity of the test pieces, there is a lack of universal test equipment and host computer software.

[0003] In addition, the existing backlight test generally uses human visual inspection, which can only distinguish obvious brightness and defects, and cannot test and analyze the more detailed backlight distribution. Long-term visual inspection will increase the labor intensity of the human eye and affect vision health. Moreover, the existing resistance test only stays at the simple detection and threshold judgment of the resistance value, and only tests and judges the quality of related components from a single perspective. This method is not refined enough and it is difficult to guide the classification and production of products. Therefore, an accurate and effective universal backlight resistance test system and test method are urgently needed. Summary of the invention

[0004] The purpose of the present invention is to provide a universal backlight resistance testing system and testing method to solve the problems raised in the background technology.

[0005] The present invention can be implemented by the following technical scheme: a universal backlight resistance test system, including host computer software and hardware control and acquisition components, the host computer software includes a ModBus communication module, a parameter configuration module, a self-test learning module, a detection judgment module and a data processing module, the hardware control and acquisition components include a hardware control and acquisition components including a function switching module, an on-off self-test module, a resistance value detection module, a backlight power supply module and an external pin module;

[0006] The host computer software communicates with the hardware control and acquisition components through the ModBus communication module. Each module in the hardware control and acquisition components is mainly implemented through an electrical connection combination including multiple C-type relays, AI interfaces and DI interfaces;

[0007] The self-test learning module in the upper computer software records and learns the on-off status of each pin when the on-off self-test module performs self-test on the standard sample. The resistance value monitoring module performs real-time testing on the resistance value under the corresponding external pin function item and the backlight power supply module supplies power to the test piece. The data processing module records the test results. At the same time, the data processing module analyzes and calculates the overall deviation rate of the resistance test and the backlight test, and scores according to the calculation results, and evaluates the quality of the test piece according to the score.

[0008] The further technical improvement of the present invention is that the normally open and normally closed contacts and the common end of the C-type relay together constitute a function switching module, and the C-type relay is marked as Y1-Y48, then the common end of Y33~Y48 is an external pin module; the AI ​​interface includes I N1+, I N1-~I N8+, I N8-, constituting a resistance value monitoring module; the backlight power supply module includes VOUT and GND, which are used to provide 12V positive electricity and grounding; the DI interface includes X1~X16, constituting a circuit breaker self-detection module.

[0009] A universal backlight resistance testing method comprises the following steps:

[0010] Step 1: Use the parameter configuration module to configure the test parameters, and the ModBus communication module establishes ModBus communication based on IP and port configuration;

[0011] Step 2: Connect the standard sample through the external pin module to perform self-test on the on / off status of each pin of the standard sample, and the self-test learning module records and learns the self-test results;

[0012] Step 3: Connect the device to be tested through the external pin module to perform a circuit break test. The detection and judgment module compares the test result with the learning record of the self-test learning module for consistency, decides whether to perform subsequent tests based on the comparison result, and records the current test result;

[0013] Step 4: The function switching module switches the contact connection state, and the pin assignment value resistance value detection module and the backlight power supply module are respectively subjected to resistance test and backlight test;

[0014] Step 5: The data processing module analyzes and processes the resistance data of the resistor test and the visual image data of the backlight test to obtain the overall deviation rate of the two, calculates and scores based on the overall deviation rate, and finally evaluates the quality of the test piece;

[0015] Step 6: The data processing module records the test results of the test items of the test piece. After replacing the test piece, repeat steps 3 to 5 to carry out subsequent tests.

[0016] A further technical improvement of the present invention is that the specific process of the resistance value test includes:

[0017] Switch the switch or gear switch of the test piece and read the feedback resistance data in real time;

[0018] The detection and judgment module compares the organizational data with the configured resistance range:

[0019] If it is within the resistance range, the resistance test passes; otherwise, it is recorded as a NG of the corresponding pin; if only one NG occurs within the set number of tests, the number of tests is increased to a certain value. If no NG occurs in the future, the test piece is put back into the upstream test queue for subsequent retesting, otherwise the test fails;

[0020] The data processing module analyzes and processes the resistance data obtained from the same batch of test pieces to obtain the resistance stability coefficient ε of the test pieces in different switch states. i and the overall deviation rate γ of the resistance data between different test pieces in the batch, where i represents the state type number of the switch or gear switch.

[0021] A further technical improvement of the present invention is that the backlight test mainly collects backlight image data through a visual camera, screens and filters the inferior backlight image data with no backlight characters or missing characters, and analyzes and processes the brightness and chromaticity distribution of the backlight characters of the test piece after filtering to obtain the overall deviation rate p of the backlight test.

[0022] A further technical improvement of the present invention is that the process of evaluating and distinguishing the quality of the test piece by the data processing module is as follows:

[0023] Based on the scoring formula, the resistance stability and backlight effect of the test piece are comprehensively scored Where α and β represent the resistance value and backlight influence weight coefficient respectively, α∈[0.45~0.72], β∈[0.42~0.55], i max Indicates the number of states of a switch or a shift switch;

[0024] When the comprehensive score exceeds the set score threshold, the tested piece is considered to be a good product, otherwise it is a good product.

[0025] A further technical improvement of the present invention is that the process of obtaining the resistance stability coefficient in the resistance test includes:

[0026] The test resistance values ​​of a single DUT in different switch states are recorded in a matrix form, where the number of rows represents the set number of tests, and the number of columns represents the number of states of the switch or gear switch;

[0027] Calculate the standard deviation S of a single column of data for a single matrix i , substitute into the formula The resistance stability coefficient ε of the test piece in switch state i is obtained from i .

[0028] A further technical improvement of the present invention is that the calculation process of the overall deviation rate of resistance data between different test pieces in the same batch in the resistance test includes:

[0029] Select the total standard deviation ΣS of each test piece i The smallest matrix is ​​used as the reference matrix D;

[0030] Calculate the difference matrix C of other matrices relative to the reference matrix;

[0031] Apply the Frobenius norm to the difference matrix and the benchmark matrix respectively and perform ratio operation to obtain the overall deviation rate, which is: where ||*|| F represents the Frobenius norm.

[0032] A further technical improvement of the present invention is that the brightness and chromaticity distribution analysis process in the backlight test includes:

[0033] S1: noise reduction and enhancement of backlight image data;

[0034] S2: using OpenCV technology to determine the backlight character trajectory, and continuously draw inscribed circles that are circumscribed to each other and inscribed to the trajectory channel in the trajectory channel, and determine the pixel coordinates and radius of the center of the corresponding inscribed circle;

[0035] S3: Count the complete pixel points in each inscribed circle, and calculate the average value of the three primary color components in each inscribed circle, which is defined as the characteristic value of the channel in the corresponding inscribed circle;

[0036] S4: convert the three-channel RGB color space into the YUV color space, and obtain the brightness Y and chromaticity value [U, V] of the corresponding inscribed circle, where U and V represent the blue chromaticity component and the red chromaticity component respectively;

[0037] S5: Calculate the average brightness of all inscribed circles and brightness standard deviation S Y , the relative standard deviation of brightness is As well as the overall brightness setting value and the average brightness value of the backlight character Deviation rate

[0038] S6: Similar to S5, first calculate the mean and standard deviation of the blue chromaticity component and the red chromaticity component in all inscribed circles, and obtain the relative standard deviation rate δ of the blue chromaticity component and the red chromaticity component U and δ V , then the relative standard deviation of chromaticity value is

[0039] S7: Combine the relevant deviation rates of chromaticity and brightness distribution to obtain the overall deviation rate p=aδ in the backlight test Y +bδ C +cλY , where a+b+c=1, and c>a≥b.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] 1. The present invention performs real-time MosBus communication through host computer software, hardware control and acquisition components, integrates multiple test requirements, and quickly proceeds to the corresponding test requirements by switching the contact state, so that the test piece does not need to be installed and disassembled multiple times, and multiple tests can be completed at one time, which greatly shortens the time required for testing and improves test efficiency.

[0042] 2. The present invention is not limited to basic resistance testing of resistors, but also further analyzes the stability of resistors, and combines machine vision technology to acquire backlight images, quickly analyze the brightness and chromaticity distribution of backlight characters, and comprehensively considers the stability of relevant parameters in resistance testing and backlight testing. A comprehensive score is given to a single test piece, and then the quality of the test piece is distinguished based on the score, and the test results of the product are classified more finely. On the other hand, it can also find the locations where problems in production are concentrated, which provides guidance value for production. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0044] Figure 1 It is a schematic diagram of the system structure of the present invention;

[0045] Figure 2 is a flow chart of the testing method of the present invention;

[0046] Figure 3 This is a wiring diagram of the hardware control and acquisition components of the present invention. DETAILED DESCRIPTION

[0047] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation methods, structures, features and effects of the present invention are described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0048] See also Figure 1-2 As shown, a universal backlight resistance test system includes a host computer software and a hardware control and acquisition component; the host computer software includes a ModBus communication module, a parameter configuration module, a self-test learning module, a detection judgment module and a data processing module; the hardware control and acquisition component includes a function switching module, an on-off self-test module, a resistance value detection module, a backlight power supply module and an external pin module;

[0049] In the hardware control and acquisition components, the wiring circuit composition of a certain embodiment is as follows: Figure 3 As shown: X1 to X16 are DI interfaces, forming a circuit-on / off self-test module, which is used to detect the circuit-on / off status between the pins of the electronic device under test;

[0050] I N1+, I N1-~I N8+, I N8- are AI interfaces, which constitute a resistance value detection module for real-time monitoring of line resistance changes; taking I N1+ and I N1- as an example, the internal circuit between I N1+ and I N1- has a power supply voltage and internal resistance, and can collect the current value after I N1+, I N1- and the external circuit form a loop in real time. When the pins of the device to be tested are connected to I N1+ and I N1- to form a loop, the resistance value between the pins of the device to be tested can be obtained. The host computer software can read the resistance value information fed back by the AI ​​interface in real time through Modbus.

[0051] VOUT and GND form the backlight power supply module, which are used to provide 12V positive power and ground respectively;

[0052] Y1-Y48 are C-type relays with normally open, normally closed contacts and a common terminal, which together constitute a function switching module; wherein the common terminal of Y33 to Y48 is an external pin module, which is used to connect the pins of the device under test to the hardware control and acquisition components; in this embodiment, the pins of the device under test are connected to PIN1 to PIN16 according to different function numbers;

[0053] Above Figure 3 The number of relays in the circuit composition can be expanded or simplified to cope with different numbers of test items.

[0054] It should be noted that when the on-off self-test is carried out, the common end of Y1 to Y16 is closed to the normally closed contact, the common end of Y17 to Y32 is closed to the normally closed contact, and the common end of Y33 to Y48 is closed to the normally open contact. At this time, the external pin module is connected to the on-off self-test module;

[0055] When the backlight test is carried out, the common end of Y1~Y16 is closed with the normally open contact, and Y17~Y48 is configured according to the corresponding pins selected as the backlight test in the parameter configuration module. For example, if the function 1 of the parameter configuration is selected as the backlight test, the common end of Y33 corresponding to the PIN1 pin is closed with the normally open contact, and the common end of Y17 is closed with the normally closed contact. At this time, the PIN1 pin is connected to the VOUT pin; the common end of Y34 corresponding to the PIN2 pin is closed with the normally open contact, and the common end of Y18 is closed with the normally open contact. At this time, the PIN2 pin is connected to the GND pin;

[0056] When carrying out resistance value test, Y33~Y48 are configured according to the corresponding pins selected as resistance value test in the parameter configuration module. For example, if function 2 of the parameter configuration is selected as resistance value test, the common end of Y35 corresponding to the PIN3 pin is closed with the normally closed contact, and the common end of Y36 corresponding to the PIN4 pin is closed with the normally closed contact. At this time, the PIN3 and PIN4 pins are connected to IN2+ and IN2- respectively.

[0057] A general backlight resistance testing method based on the above system includes:

[0058] Step 1: Use the parameter configuration module to configure the test parameters, including the device IP address and port number, the number of function tests, the function number and function item of the corresponding external pin, whether to perform association tests between different function items, and different resistance test gears and resistance ranges;

[0059] Step 2: The ModBus communication module establishes ModBus communication between the host computer software and the hardware control and acquisition components based on the device IP address and port number configured in the above step 1;

[0060] Step 3: Connect the standard sample through the external pin module. First, the on-off status of each pin of the standard sample is self-checked through the on-off self-check module, and the on-off status of each pin of the corresponding standard sample is obtained through the self-check learning module. Specifically:

[0061] S31: The host computer software controls the common end of Y33 to Y48 to close with the normally open contact, and the common end of Y17 to Y32 to close with the normally closed contact through the Modbus communication module. The standard sample pins are simultaneously connected to the common end of Y1 to Y16 and X1 to X16;

[0062] S32: The host computer software controls the common end of Y1 and the normally open contact to close through the Modbus communication module, and the common ends of the rest of Y2 to Y16 and the normally closed contacts to close. At this time, VOUT is connected to Y1, and since VOUT provides 12V positive electricity, it reaches the trigger range of the DI interface, so X1 connected to Y1 is triggered;

[0063] It should be noted that at this time, if there is a short circuit between PIN2~PIN16 and the standard sample pins connected to PIN1, the corresponding DI interface in X2~X16 will also be triggered. If it is not triggered, it means that the circuit is open.

[0064] S33, the self-check learning module Modbus communication module reads the status of X1~X16 and records the on / off status of the PIN1 pin;

[0065] S34. According to steps S32 to S33, Y2 to Y16 are traversed in sequence and corresponding control and on / off status records are performed.

[0066] Step 4: Connect the device to be tested through the external pin module, and perform an on-off test on the standard sample in step 3, so as to record the on-off status of the corresponding pins. The detection and judgment module compares the on-off status of the corresponding pins of the device to be tested with the on-off status of the corresponding pins of the standard sample. When the comparison results of each pin are consistent, it means that the on-off test of the device to be tested has passed, and the subsequent steps continue; otherwise, it fails, and the pin numbers and current states of the inconsistent states are recorded, and another device to be tested is reconnected to execute this step;

[0067] Step 5: The function switching module allocates the pins of the device to be tested to the resistance value detection module and the backlight power supply module according to the external pin function items configured in the parameter configuration module, and performs resistance test and backlight test respectively. Specifically:

[0068] S51: The host computer software selects the Y33~Y48 common terminal corresponding to the pin for resistance test through the Modbus communication module control function and closes the normally closed contact;

[0069] S52: The tester operates or uses a manipulator to operate the switch or gear switch of the test piece that needs to be tested for resistance. The upper computer software reads the resistance data fed back by the AI ​​interface in real time through Modbus. The detection and judgment module compares it according to the pre-configured resistance range. When the resistance data is within the resistance range, the test passes. When it exceeds the resistance range, it is recorded as an NG and corresponds to the corresponding pin. When only one NG occurs within the set number of detections, the set number of detections for the pin is increased to a certain value. When there is no resistance exceeding the value again, it flows back to the upstream of the test piece to be tested and waits in the queue for another round of detection; otherwise, the test is directly considered to have failed and is defined as a defective product;

[0070] S53: Traditional backlight detection basically uses manual visual inspection, but this method not only cannot guarantee accuracy and efficiency, but also puts a lot of pressure on the eyes of workers; the method using brightness meter and colorimeter requires adjusting the position of the instrument to measure point by point, which is inefficient;

[0071] During the backlight test, the common terminals of Y1 to Y16 are closed with the normally open contacts, and Y17 to Y48 are configured as the corresponding pins of the backlight test according to the function selection in the parameter configuration module;

[0072] A visual camera is used to obtain the backlight image data of the test piece in a stable darkroom environment and import it into the data processing module for chromaticity and brightness distribution evaluation, and finally combined.

[0073] Step 6: The data processing module records the test results of the test items of the test piece, and replaces the test piece to repeat steps 4 to 5 to carry out the next round of testing.

[0074] It should be noted that the data processing module acquires and analyzes multiple test resistance values ​​of corresponding pins of a single device to be tested, taking each production batch as a unit:

[0075] First, the data processing module records multiple test resistance values ​​of a single test piece under different switch states or switch gears in the form of a matrix; for a single matrix, the number of rows represents the set number of detections, and the number of columns represents the number of types of switch states of the test piece or the number of gears of the switch of the test piece;

[0076] In each matrix, find the standard deviation S of the data in a single column i , the discreteness and stability of the test resistance value under the corresponding state can be obtained. When the standard deviation under a certain state exceeds the set standard deviation threshold, it means that the stability under this state is poor, otherwise it means that the stability under this state is high;

[0077] Using the formula Define the resistance stability coefficient ε in the i-th column of the matrix i ,when When , it means that the stability of the resistance value is poor;

[0078] Secondly, compare the overall deviation rate γ between the corresponding matrices of different test pieces in the same batch:

[0079] Select the total standard deviation ΣS i The smallest matrix is ​​used as the reference matrix D;

[0080] Calculate the difference matrix C of other matrices relative to the reference matrix (i.e., subtract corresponding elements);

[0081] Apply the Frobenius norm to the difference matrix and the benchmark matrix respectively and perform ratio operation to obtain the overall deviation rate, which is: where ||*|| F represents the Frobenius norm.

[0082] Furthermore, the specific process of evaluating the chromaticity and brightness distribution in the data processing module includes:

[0083] (1) Compare the backlight image data with the standard image. If the backlight character does not exist in the backlight image data or the backlight character is missing, it is directly defined as a defective product; otherwise, proceed to the subsequent steps;

[0084] (2) Preprocessing the backlit image data collected by the visual camera, including image noise reduction and image enhancement. The noise reduction process filters individual spots in the image. The image enhancement process uses pseudo-color image processing technology, that is, to establish a mapping relationship between each grayscale level in the grayscale processed image and a point in the color gamut, that is, to convert the grayscale value g(x,y) of the pixel point (x,y) into the three primary color components in the RGB format;

[0085] (3) Perform edge detection and contour search based on OpenCV to determine the trajectory channel of the character, draw several maximum inscribed circles of the channels (assuming there are M) in the trajectory channel, and circumscribe two adjacent maximum inscribed circles to obtain the pixel coordinates (x m ,y m ) and the corresponding radius r m ;

[0086] (4) Count the number of complete pixels N in each maximum inscribed circle, and then calculate the average value of the three primary color components in the maximum inscribed circle, that is, in They represent the coordinates of the jth complete pixel point in the mth maximum inscribed circle, It represents the R channel component value of the jth complete pixel point in the mth largest inscribed circle, R m Represents the R channel eigenvalue of the mth largest inscribed circle; similarly, the G channel and B channel eigenvalues ​​G corresponding to the largest inscribed circle can be obtained. m and B m ;

[0087] (5) Convert the RGB color space to the YUV color space, where Y represents brightness, U and V represent the blue chromaticity component and the red chromaticity component, respectively. The specific conversion relationship is:

[0088]

[0089] Then, for the brightness, the brightness value Y of each maximum inscribed circle in the backlight character channel is obtained. m ;

[0090] For chromaticity, the chromaticity value of each maximum inscribed circle in the backlight character channel is obtained [U m ,V m ].

[0091] (6) Calculate the average brightness value of all maximum inscribed circles of the backlight character and standard deviation S Y , so its relative standard deviation is At the same time, calculate the overall brightness setting value and the average brightness value of the backlight character Deviation rate

[0092] Similarly, the mean and standard deviation of the chromaticity scores of each maximum inscribed circle of the backlight character are solved, and the corresponding relative standard deviation rate δ is obtained. U and δ V , then the relative standard deviation of the chromaticity value is

[0093] (7) Based on the relative deviation rates of chromaticity and brightness distribution, the overall deviation rate in the backlight test is obtained as p = aδ Y +bδ C +cλ Y , where a+b+c=1, and c>a≥b;

[0094] The data processing module evaluates and distinguishes the quality of the test pieces based on the overall deviation rate in the resistance test and backlight test:

[0095] The scoring formula used for evaluation is α and β represent the resistance influence weight coefficient and the backlight influence weight coefficient respectively, which are the expert experience values. Generally, α∈[0.45~0.72], β∈[0.42~0.55], i max Represents the total number of columns of the matrix used to record resistance data;

[0096] A scoring threshold is set. When the score exceeds the threshold, the quality of the test piece is considered to be excellent; when the score is lower than the threshold, the quality of the test piece is considered to be good; and the test piece that fails the test is considered to be inferior.

[0097] Furthermore, the rate of superior products, good quality products and inferior products in each production batch can be obtained. According to the records, the concentrated locations of product problems in the production batch can also be tracked, thus providing guidance for production.

[0098] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A universal backlight resistance test system, characterized in that: It includes host computer software and hardware control and acquisition components, wherein the host computer software includes a ModBus communication module, a parameter configuration module, a self-test learning module, a detection and judgment module, and a data processing module, and the hardware control and acquisition components include a hardware control and acquisition component including a function switching module, an on-off self-test module, a resistance value detection module, a backlight power supply module, and an external pin module; The host computer software communicates with the hardware control and acquisition components through the ModBus communication module. Each module in the hardware control and acquisition components is mainly implemented through an electrical connection combination including multiple C-type relays, AI interfaces and DI interfaces; The self-test learning module in the upper computer software records and learns the on-off status of each pin when the on-off self-test module performs self-test on the standard sample. The resistance value monitoring module performs real-time testing on the resistance value under the corresponding external pin function item and the backlight power supply module supplies power to the test piece. The data processing module records the test results. At the same time, the data processing module analyzes and calculates the overall deviation rate of the resistance test and the backlight test, and scores according to the calculation results, and evaluates the quality of the test piece according to the score.

2. A universal backlight resistance testing system according to claim 1, characterized in that: The normally open, normally closed contacts and common end of the C-type relay together constitute a function switching module. The C-type relay is marked as Y1-Y48, and the common end of Y33~Y48 is an external pin module; the AI ​​interface includes IN1+, IN1-~IN8+, IN8-, constituting a resistance value monitoring module; the backlight power supply module includes VOUT and GND, which are used to provide 12V positive electricity and grounding; the DI interface includes X1~X16, constituting a circuit breaker self-detection module.

3. A universal backlight resistance testing method of the testing system according to any one of claims 1 or 2, characterized in that: The steps include: Step 1: Use the parameter configuration module to configure the test parameters, and the ModBus communication module establishes ModBus communication based on IP and port configuration; Step 2: Connect the standard sample through the external pin module to perform self-test on the on / off status of each pin of the standard sample, and the self-test learning module records and learns the self-test results; Step 3: Connect the device to be tested through the external pin module to perform a circuit break test. The detection and judgment module compares the test result with the learning record of the self-test learning module for consistency, decides whether to perform subsequent tests based on the comparison result, and records the current test result; Step 4: The function switching module switches the contact connection state, and the pin assignment value resistance value detection module and the backlight power supply module are respectively subjected to resistance test and backlight test; Step 5: The data processing module analyzes and processes the resistance data of the resistor test and the visual image data of the backlight test to obtain the overall deviation rate of the two, calculates and scores based on the overall deviation rate, and finally evaluates the quality of the test piece; Step 6: The data processing module records the test results of the test items of the test piece. After replacing the test piece, repeat steps 3 to 5 to carry out subsequent tests.

4. A universal backlight resistance testing method according to claim 3, characterized in that: The specific process of the resistance test includes: Switch the switch or gear switch of the test piece and read the feedback resistance data in real time; The detection and judgment module compares the organizational data with the configured resistance range: If it is within the resistance range, the resistance test passes; otherwise, it is recorded as a NG of the corresponding pin; if only one NG occurs within the set number of tests, the number of tests is increased to a certain value. If no NG occurs in the future, the test piece is put back into the upstream test queue for subsequent retesting, otherwise the test fails; The data processing module analyzes and processes the resistance data obtained from the same batch of test pieces to obtain the resistance stability coefficient ε of the test pieces in different switch states. i and the overall deviation rate γ of the resistance data between different test pieces in the batch, where i represents the state type number of the switch or gear switch.

5. A universal backlight resistance testing method according to claim 4, characterized in that: The backlight test mainly collects backlight image data through a visual camera, screens and filters the inferior backlight image data with no backlight characters or missing characters, and analyzes and processes the brightness and chromaticity distribution of the backlight characters of the tested pieces after filtering to obtain the overall deviation rate p of the backlight test.

6. A universal backlight resistance testing method according to claim 5, characterized in that: The process of evaluating and distinguishing the quality of the test piece by the data processing module is as follows: Based on the scoring formula, the resistance stability and backlight effect of the test piece are comprehensively scored Where α and β represent the resistance value and backlight influence weight coefficient respectively, α∈[0.45~0.72], β∈[0.42~0.55], i max Indicates the number of states of a switch or a shift switch; When the comprehensive score exceeds the set score threshold, the tested piece is considered to be a good product, otherwise it is a good product.

7. A universal backlight resistance testing method according to claim 4, characterized in that: The process of obtaining the resistance stability coefficient in the resistance test includes: The test resistance values ​​of a single DUT in different switch states are recorded in a matrix form, where the number of rows represents the set number of tests, and the number of columns represents the number of states of the switch or gear switch; Calculate the standard deviation S of a single column of data for a single matrix i , substitute into the formula The resistance stability coefficient ε of the test piece in switch state i is obtained from i .

8. A universal backlight resistance testing method according to claim 7, characterized in that: The calculation process of the overall deviation rate of the resistance data between different test pieces in the same batch in the resistance test includes: Select the total standard deviation ΣS of each test piece i The smallest matrix is ​​used as the reference matrix D; Calculate the difference matrix C of other matrices relative to the reference matrix; Apply the Frobenius norm to the difference matrix and the benchmark matrix respectively and perform ratio operation to obtain the overall deviation rate, which is: where ||*|| F represents the Frobenius norm.

9. A universal backlight resistance testing method according to claim 5, characterized in that: The brightness and chromaticity distribution analysis process in the backlight test includes: S1: noise reduction and enhancement of backlight image data; S2: using OpenCV technology to determine the backlight character trajectory, and continuously draw inscribed circles that are circumscribed to each other and inscribed to the trajectory channel in the trajectory channel, and determine the pixel coordinates and radius of the center of the corresponding inscribed circle; S3: Count the complete pixel points in each inscribed circle, and calculate the average value of the three primary color components in each inscribed circle, which is defined as the characteristic value of the channel in the corresponding inscribed circle; S4: convert the three-channel RGB color space into the YUV color space, and obtain the brightness Y and chromaticity value [U, V] of the corresponding inscribed circle, where U and V represent the blue chromaticity component and the red chromaticity component respectively; S5: Calculate the average brightness of all inscribed circles and brightness standard deviation S Y , the relative standard deviation of brightness is As well as the overall brightness setting value and the average brightness value of the backlight character Deviation rate S6: Similar to S5, first calculate the mean and standard deviation of the blue chromaticity component and the red chromaticity component in all inscribed circles, and obtain the relative standard deviation rate δ of the blue chromaticity component and the red chromaticity component U and δ V , then the relative standard deviation of chromaticity value is S7: Combine the relevant deviation rates of chromaticity and brightness distribution to obtain the overall deviation rate in the backlight test p=aδ Y +bδ C +cλ Y , where a+b+c=1, and c>a≥b.

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