CN-121994461-A - LED test circuit and test method thereof

CN121994461ACN 121994461 ACN121994461 ACN 121994461ACN-121994461-A

Abstract

The application relates to the technical field of online testing of light-emitting diode production and manufacturing, and provides an LED testing circuit and a testing method thereof. The method comprises the steps of providing a test power supply for a plate to be tested, which is provided with multicolor light emitting diodes to be tested, lighting the light emitting diode lamps with different colors on the plate to be tested one by one according to preset colors, collecting three paths of currently-lighting photosensitive parameters through a photosensitive sensor after each light emitting diode with one color to be tested is lighted, comparing the three paths of photosensitive parameters, determining the color actually emitted by the current light emitting diode according to the size relation of the three paths of photosensitive parameters according to preset color judging logic, comparing the color actually obtained by actual judgment with the preset color which is lighted currently, judging that the light emitting diode works normally if the color is consistent, judging that the light emitting diode works abnormally if the color is inconsistent, and successively completing the test of the light emitting diodes with all the colors to be tested to obtain the final LED test result.

Inventors

SUN HONGFENG
WANG KAI
HUANG QINGYUN

Assignees

深圳市振云精密测试设备有限公司

Dates

Publication Date: 20260508
Application Date: 20260409

Claims (10)

1. A method of testing an LED test circuit, comprising: providing a test power supply for a plate to be tested provided with the multicolor light-emitting diode to be tested, and lighting the light-emitting diode lamps with different colors on the plate to be tested one by one according to a preset color; After each light-emitting diode with a color to be detected is lightened, three paths of photosensitive parameters of current light emission are collected through a photosensitive sensor, the three paths of photosensitive parameters are compared in size, and the color actually emitted by the current light-emitting diode is determined according to the size relation of the three paths of photosensitive parameters according to preset color judgment logic; comparing the color obtained by actual judgment with the preset color which is lighted at present, judging that the light emitting diode works normally if the color is consistent, judging that the light emitting diode works abnormally if the color is inconsistent, and sequentially completing the test of the light emitting diodes with all colors to be detected to obtain the final LED test result.
2. The method of claim 1, wherein the step of supplying the test power to the board to be tested on which the multicolor light emitting diode to be tested is mounted, and lighting the light emitting diode lamps of different colors on the board to be tested one by one according to the preset color comprises: according to the color lighting sequence corresponding to the preset color, only a light emitting diode corresponding to one color channel is lighted each time, after the lighting operation is completed, the lighting stable time with the preset duration is reserved, and then the subsequent photosensitive parameter acquisition step is executed.
3. The method according to claim 1, wherein each time a led of a color to be detected is lighted, three photosensitive parameters of the current light emission are collected by the photosensitive sensor, including: and acquiring three paths of original photosensitive values of current luminescence through a photosensitive sensor, converting the three paths of original photosensitive values into decimal values, and acquiring the three paths of photosensitive parameters.
4. The method of claim 1, wherein the three-way exposure parameters include a first-way parameter value, a second-way parameter value, and a third-way parameter value, wherein the comparing the magnitudes of the three-way exposure parameters according to a predetermined color decision logic, and determining the color actually emitted by the current light emitting diode according to the magnitude relation of the three-way exposure parameters comprises: If the first path of parameter value is larger than the second path of parameter value and the third path of parameter value, the difference value is larger than the preset difference value, and the first path of parameter value is larger than the second path of parameter value, and the second path of parameter value is larger than the third path of parameter value, the actual color is judged to be red light; if the second path parameter value is larger than the first path parameter value and the third path parameter value, the difference value is larger than the preset difference value, and the second path parameter value is larger than the third path parameter value, and the third path parameter value is larger than the first path parameter value, the actual color is judged to be green light; if the third path of parameter values are far greater than the first path of parameter values and the second path of parameter values, the difference values are greater than the preset difference values, the third path of parameter values are greater than the second path of parameter values, the second path of parameter values are greater than the first path of parameter values, and the actual color is judged to be blue light; And if the corresponding difference value among the first path parameter value, the second path parameter value and the third path parameter value is smaller than or equal to the preset difference value, judging that the actual color is white light.
5. The method according to claim 1, wherein comparing the color obtained by the actual determination with the preset color that is currently lit, if the colors are consistent, determining that the light emitting diode is working normally, and if the colors are inconsistent, determining that the light emitting diode is working abnormally, comprises: After each comparison is completed, the position, the preset color, the actual judgment color and the judgment result of the current light emitting diode are stored in a test buffer, all the judgment results of all the light emitting diodes are arranged to generate test records after all the tests are completed, and information of all the light emitting diodes with abnormal work is marked.
6. The method according to claim 1, wherein the method further comprises: before all the LEDs are lighted, three paths of photosensitive reference parameters under the ambient light are collected in advance, after the photosensitive parameters of the LEDs which are currently lighted are collected each time, the influence of the corresponding ambient light reference parameters is removed from the collected three paths of parameters respectively, corrected photosensitive parameters after ambient light interference is eliminated are obtained, and then the corrected photosensitive parameters are used for executing the subsequent size comparison step, so that the ambient light interference test result of the production site is avoided.
7. The method according to claim 1, wherein the method further comprises: After the plate test of the preset number is completed, the calibration flow of the photosensitive sensor is automatically triggered, the light source of the preset standard color is controlled to sequentially emit light rays of the preset standard color, photosensitive parameters corresponding to the standard colors are sequentially collected, the collected parameters are compared with the standard parameter range, the gain gear of the photosensitive sensor is adjusted, the collected parameters fall into the standard parameter range, automatic calibration is completed, and the accuracy of long-term batch test is guaranteed.
8. The method according to claim 1, wherein the method further comprises: Collecting test data of all unqualified LED plates marked with actual abnormal reasons in a batch production process in advance, training the marked test data to obtain an abnormal reason intelligent classification model, extracting the deviation degree of photosensitive parameters of all channels of the plate and the position distribution characteristics of abnormal channels after all the test is completed to obtain all abnormal results and corresponding test parameters of the current plate to be tested, inputting the extracted characteristics into the trained abnormal reason intelligent classification model, obtaining specific abnormal reasons corresponding to the current unqualified plate through model reasoning, particularly distinguishing four different abnormal types including LED body color cast abnormality, pin cold joint contact abnormality, power supply channel abnormality and control logic abnormality, transmitting the abnormal types and corresponding position information to a repair management system, and automatically pushing a standardized repair guidance scheme corresponding to the abnormal types, thereby facilitating maintenance personnel to quickly locate fault points.
9. The method according to claim 1, wherein the method further comprises: After the plates to be tested of the same model and the same batch are tested by the preset quantity, extracting photosensitive parameter data of all the qualified plates corresponding to each color, carrying out cluster analysis on parameter distribution of each color, identifying parameter integral deviation of the current batch caused by LED production consistency deviation, automatically adjusting a color judgment threshold value of a subsequent test of the current batch according to the deviation, replacing a general threshold value stored in a parameter library, executing color judgment by the subsequent plate test of the same batch by using the adjusted new threshold value, avoiding test misjudgment caused by inherent brightness deviation of LEDs of different batches, and improving the accuracy of batch test.
10. The LED test circuit is characterized by comprising a power supply module, a light sensing sensor and a control unit; the power supply module is used for providing a test power supply for the plate to be tested provided with the multicolor light emitting diode to be tested; The light sensing sensor is arranged at a corresponding light sensing position of the light emitting diode to be detected and is used for collecting three light sensing parameters of light output by the light emitting diode after being lightened; The control unit is respectively and electrically connected with the power supply module, the light sensing sensor and the light emitting control end of the plate to be tested, and the control unit is used for realizing the method as set forth in any one of claims 1-9.

Description

LED test circuit and test method thereof Technical Field The application relates to the technical field of online testing of light-emitting diode production and manufacturing, in particular to an LED test circuit and a test method thereof. Background The multicolor integrated LED is widely applied to the fields of display modules, intelligent marks, consumer electronics backlight and the like, and the working states of all color channels of the LED plate must be tested in the mass production process, so that bad outflow such as wrong installation, color cast, channel failure and the like can be avoided. The conventional multi-color LED test scheme in the mass production stage is mainly divided into three types, namely, manual visual detection, human eyes are relied on to judge whether colors are qualified or not, the method is low in efficiency, high in subjectivity and high in error leakage rate, cannot adapt to high-speed production line production, professional spectrometers are used for detection, the accuracy is high, the equipment cost is high, a single test takes a long time and cannot be used for large-scale online test by collecting complete emission spectrums and standard color comparison, the conventional automatic conduction test is used for detecting whether an LED channel is conducted or not, whether brightness reaches the standard or not, judging on actual luminous colors is avoided, error assembly and color cast defects cannot be detected, fewer automatic schemes capable of realizing color detection are also required to be used for calibrating absolute thresholds of colors in different models and batches in advance, multiple threshold matching calculation is required to be completed after parameters are collected, the process is complex, the requirement on hardware is high, and misjudgment is easy to occur due to LED batchwise brightness deviation. Disclosure of Invention The application provides an LED test circuit and a test method thereof, and aims to solve the problems that the existing multicolor LED test scheme in the mass production stage is low in efficiency, strong in subjectivity and high in error leakage rate, and cannot be suitable for high-speed pipeline production. In a first aspect, an embodiment of the present application provides a method for testing an LED test circuit, where the method includes: providing a test power supply for a plate to be tested provided with the multicolor light-emitting diode to be tested, and lighting the light-emitting diode lamps with different colors on the plate to be tested one by one according to a preset color; After each light-emitting diode with a color to be detected is lightened, three paths of photosensitive parameters of current light emission are collected through a photosensitive sensor, the three paths of photosensitive parameters are compared in size, and the color actually emitted by the current light-emitting diode is determined according to the size relation of the three paths of photosensitive parameters according to preset color judgment logic; comparing the color obtained by actual judgment with the preset color which is lighted at present, judging that the light emitting diode works normally if the color is consistent, judging that the light emitting diode works abnormally if the color is inconsistent, and sequentially completing the test of the light emitting diodes with all colors to be detected to obtain the final LED test result. In some embodiments, the step of providing a test power supply to the board to be tested provided with the multicolor light emitting diode to be tested, and lighting the light emitting diode lamps with different colors on the board to be tested one by one according to a preset color comprises lighting only the light emitting diode corresponding to one color channel at a time according to a color lighting sequence corresponding to the preset color, reserving a lighting stabilization time with a preset duration after lighting operation is completed, and executing a subsequent photosensitive parameter acquisition step. In some embodiments, collecting three paths of currently-emitted light sensing parameters through a light sensing sensor after each light emitting diode with a color to be detected is lightened comprises collecting three paths of currently-emitted original light sensing values through the light sensing sensor, converting the three paths of original light sensing values into decimal values, and obtaining the three paths of light sensing parameters. In some embodiments, the three-way photosensitive parameters comprise a first-way parameter value, a second-way parameter value and a third-way parameter value, the three-way photosensitive parameters are subjected to size comparison, the actual color emitted by the current light emitting diode is determined according to the size relation of the three-way photosensitive parameters according to preset color determination logic, the three-way