CP test light source partition of image sensor and control method of CP test light source partition

Abstract

The invention relates to a CP test light source partition of an image sensor and a control method of the CP test light source partition, and aims to solve the problem of test errors caused by non-uniformity of an existing CP test light source. According to the light source, the light source is divided into a plurality of independent subareas, the illumination intensity of each subarea is regulated and controlled through the independent driving unit, and it is ensured that the light source is evenly distributed in each subarea. The light source comprises a light emitting unit, a partition control unit and a driving unit. The partition control unit divides the light source into a plurality of partitions according to distribution of Sites on the image sensor chip, and adjusts the illumination intensity in real time through a feedback mechanism. By establishing an illumination data acquisition and calibration model, it is ensured that the illumination intensity of each partition reaches the test consistency requirement that the illumination intensity is larger than or equal to 99%. According to the light source control method, the light source deviation is corrected through real-time feedback, the error of uneven light sources in a traditional method is avoided, and the consistency and stability of testing are improved. Extra hardware or manual operation is not needed, the method is suitable for CIS chip mass production testing, and the efficiency and accuracy of multi-Site simultaneous testing are effectively improved.

Description

Technical Field

[0001] This invention relates to the field of image sensor CP testing, and more particularly to an image sensor CP testing light source partitioning and its control method. Background Technology

[0002] With the continuous advancement of image sensor technology, CMOS image sensors (CIS) are increasingly widely used in consumer electronics, industrial automation, medical devices, and other fields. When CIS captures images, it requires illuminating the sensor with a test light source to evaluate its performance, and the uniformity of the light source plays a crucial role in the accuracy of the test results. However, in existing CIS testing processes, the non-uniformity of the light source often leads to differences in illumination intensity between different test areas. This difference not only affects the stability of the test results but may also cause measurement errors, thus impacting the quality assessment of the image sensor.

[0003] Currently, traditional image sensor light source testing methods typically employ fixed light source illumination or simple light source distribution adjustment devices. However, these methods have significant shortcomings. First, fixed light source illumination is difficult to adapt to the lighting requirements of different sites on a CIS chip, especially when the CIS chip is large or contains multiple test areas, where significant regional differences in light intensity may exist. Second, in existing technologies, many systems compensate for light source non-uniformity through manual adjustment or external optical devices (such as optical films), but this method is complex to operate, cannot achieve precise control, and is prone to introducing human error. Furthermore, with the continuous miniaturization of image sensor chips, the challenges faced by traditional light source testing methods are becoming increasingly severe. Traditional light source uniformity adjustment methods are insufficient to meet the requirements of high-precision, multi-site simultaneous testing, especially under the high efficiency requirements of mass production testing, where the uniformity and stability of the light source are particularly important.

[0004] Therefore, a novel light source control method is urgently needed that can adapt to the requirements of multi-site testing while ensuring light source uniformity. By independently controlling the light intensity of each test area (Site), testing errors caused by uneven light source distribution between different areas can be effectively avoided. Furthermore, automating precise light source adjustment without additional complex operations is crucial for improving testing efficiency and stability. Summary of the Invention

[0005] To address the problems existing in the prior art, the present invention provides a light source for image sensor CP testing, the light source comprising: a light-emitting unit for emitting light; a partition control unit for dividing the light source into multiple independent light source partitions according to the distribution coordinates of each Site on the image sensor chip; each light source partition is equipped with an independent driving unit for independently controlling the light intensity of that partition.

[0006] Furthermore, the light-emitting unit is an LED light source or a laser light source.

[0007] Furthermore, the partition control unit precisely divides the light source into partitions according to the layout of the image sensor chip, and adjusts the light intensity of each partition to a predetermined value.

[0008] Furthermore, the drive unit includes a feedback control system for adjusting the light intensity in real time.

[0009] Furthermore, the light-emitting unit and the driving unit work together to ensure that the light intensity of the light source is evenly distributed in each partition.

[0010] The present invention also provides a control method for the light source as described above, comprising the following steps: Step 1: Based on the distribution coordinates of each Site on the image sensor chip, divide the light source into multiple independent light source zones; Step 2: Acquire initial illumination data for each zone using the image sensor chip; Step 3: Based on the collected illumination data, establish a calibration model for the luminous parameters of each zone, and calibrate the luminous intensity of the light source in each zone according to the model; Step 4: Adjust the light intensity of each zone using an independent drive unit to ensure that the light source is evenly distributed in each zone.

[0011] Furthermore, in step 3, the calibration model, in conjunction with the requirement of ≥99% site-to-site consistency, calculates and adjusts the required light source intensity for each zone.

[0012] Furthermore, the method further includes introducing a real-time feedback mechanism during the light source intensity adjustment process to dynamically correct light source intensity deviations.

[0013] Furthermore, the real-time feedback mechanism monitors the deviation between the actual luminous intensity of the light source and the set value, and adjusts the light source intensity in real time to ensure the uniformity of illumination in each zone.

[0014] Furthermore, the method is applicable to mass production testing of CIS chips, improving testing efficiency and reducing testing errors.

[0015] Compared with the prior art, the present invention has significant technical advantages and beneficial effects, mainly reflected in the control of light source uniformity, improvement of testing accuracy and efficiency.

[0016] First, this invention effectively solves the problem of light source non-uniformity in existing technologies by dividing the light source into multiple independent zones and using independent driving units to precisely control the light intensity of each zone. Traditional light source control methods struggle to ensure consistency of the light source across different sites, leading to testing errors. The zone control method of this invention ensures uniform light intensity in each zone, thereby effectively eliminating errors caused by light source non-uniformity and improving the consistency and reliability of test results.

[0017] Secondly, this invention introduces a real-time feedback mechanism that can dynamically correct deviations in light intensity. This means that during the testing process, the actual luminous intensity of the light source is adjusted in a timely manner based on feedback data, eliminating instability caused by factors such as light source aging and environmental changes. This adaptive adjustment ensures the long-term stability of the light source throughout the testing process, whereas traditional methods often lack this real-time adjustment function, which can easily lead to light source deviations and inconsistencies in testing.

[0018] Furthermore, the light source control method of this invention does not rely on complex hardware or manual intervention, simplifying the testing process and improving the level of automation. Through precise zoning control and real-time feedback, this invention can significantly improve testing efficiency and shorten testing time in multi-site testing, while avoiding errors caused by human operation, thus effectively improving the speed and accuracy of mass production testing. This invention, through its light source zoning control, real-time feedback adjustment, and automated adjustment methods, has significant advantages over existing technologies in improving light source uniformity, testing accuracy, and production efficiency, and is particularly suitable for mass production testing of image sensor chips. Attached Figure Description

[0019] Figure 1-2 A schematic diagram of the light source used for testing the CP (Content Process) of an image sensor in existing technology; Figure 3-4 This is a schematic diagram of the partitioned light source used for testing the CP image sensor employed in this invention. Detailed Implementation

[0020] like Figure 1 As shown, a light source 100 is commonly used in the prior art for testing image sensors CP, wherein the light source 100 has an integrated controllable light-emitting unit 100A.

[0021] To address the technical problems existing in the prior art, this invention proposes a light source and its control method for CP testing of image sensors. Example 1

[0022] This invention provides a light source for CP testing of image sensors, specifically as follows: Figure 2 As shown, the light source mainly includes components such as a light-emitting unit, a zone control unit, a driving unit, and a real-time feedback module. Through the coordinated work of these components, the light intensity of the light source in each zone can be precisely controlled, ensuring that the image sensor 101 can obtain uniform illumination during the test, thereby improving the accuracy and consistency of the test results.

[0023] The design of the light source 100 can utilize either an LED or laser light source depending on actual needs. Considering cost and power consumption, LED light sources offer better cost-effectiveness in practical applications; therefore, a high-brightness LED light source is selected in this embodiment. The light source 100 consists of multiple LED light sources, and power is distributed through a unified power management module. This light-emitting unit 100 provides the necessary illumination to the image sensor through a uniform illumination beam.

[0024] The function of the partition control unit is to divide the light-emitting unit into multiple independent partition light-emitting units 100B and ensure that the illumination intensity of each partition light-emitting unit 100B can be adjusted independently. Specifically, the partition control unit uses a high-precision positioning system to divide the light source area into several partitions according to the size and structure of the image sensor chip. Each partition can cover one or more sites on the sensor chip, ensuring that the illumination intensity of each test area meets the predetermined requirements. The illumination intensity of each partition is adjusted by its corresponding drive unit. The partition control unit calculates and optimizes the light source intensity of each partition using a built-in algorithm to ensure that the light source is uniformly distributed within each partition.

[0025] The driver unit is the core component for controlling the light source's luminous intensity. Each driver unit controls the LED light source in its corresponding zone, adjusting the brightness of each LED using PWM (Pulse Width Modulation) technology. PWM modulation allows for precise control of the LED's luminous intensity, ensuring it meets the light source's adjustment requirements. The driver unit's output signal is dynamically adjusted according to the instructions of the zone control unit and can self-correct with the assistance of a real-time feedback mechanism. To improve system reliability and accuracy, each driver unit has fault detection and self-recovery functions. If a driver unit malfunctions, the system automatically switches to a backup driver unit to ensure the normal operation of the light source.

[0026] The real-time feedback module uses the photoelectric sensor of the image sensor chip to collect illumination data for each zone in real time and transmits the data to the zone control unit. The zone control unit compares this data with predetermined target values ​​to determine whether the light source intensity meets the requirements. If a deviation is detected, the system immediately adjusts the control signal of the drive unit to correct the illumination intensity, ensuring the stability of the light source during the test. This real-time feedback mechanism has a dynamic adjustment function, which can continuously correct the light source intensity during long-term testing, preventing illumination changes caused by light source aging or environmental factors.

[0027] Through the design of this embodiment, the CP test light source can provide uniform illumination intensity in each test area of ​​the image sensor, solving the error problem caused by uneven light source in traditional methods. The illumination intensity of each zone can remain stable throughout the test, and due to the introduction of the real-time feedback mechanism, the system can automatically adjust and correct any possible deviations, ensuring the consistency and reliability of the test results. Example 2

[0028] This invention also provides a light source control method for image sensor CP testing. This embodiment describes how the light source control method of this invention can achieve precise adjustment of the light source, thereby ensuring uniform illumination of the image sensor during CP testing. The method includes steps such as zoned control of the light source, real-time data acquisition and feedback, illumination intensity adjustment, and dynamic correction. Specifically, it includes the following steps: Step 1: First, based on the layout of the image sensor chip and testing requirements, the light source needs to be divided into multiple independent light source zones. The division is based on the site distribution of the image sensor chip. During this process, the zone control unit precisely determines the boundaries of each zone according to the sensor's size and shape, and allocates the light source output to each zone. The zone division considers not only the physical size of the chip but also the illumination requirements of each site. For example, some areas may require stronger illumination due to their location, while other areas may only require lower intensity. By comprehensively considering these requirements, the zone control unit can accurately allocate the light source intensity to each zone.

[0029] Step Two: After the light source division is completed, the image sensor 101 collects initial illumination data for each zone using its built-in photoelectric sensor. This data includes the illumination intensity value for each site, reflecting the uniformity of the current light source distribution. By comparing the collected data with a predetermined illumination standard, the system can calculate the light source deviation for each zone and adjust the illumination intensity of each zone by establishing a calibration model. This calibration model is based on statistical analysis methods, processing a large amount of test data to predict and calibrate the optimal illumination intensity for each zone. The model's establishment not only considers the initial data but also the effects of environmental factors and light source aging to ensure the accuracy of the calibration results.

[0030] Step 3: Based on the illumination data and calibration model obtained in Step 2, the system precisely adjusts the light source intensity of each zone's 100B emitting unit through the drive unit. Each drive unit performs PWM adjustment according to the instructions issued by the zone control unit to achieve the expected illumination intensity. During this process, a real-time feedback mechanism continuously monitors the light source intensity and compares the actual value with the preset value. If the system detects any deviation, the real-time feedback mechanism immediately adjusts the output signal of the drive unit to correct the illumination intensity. This real-time correction function can maintain the stability of illumination under the influence of factors such as light source aging and changes in ambient light.

[0031] Step Four: During the testing process, the light intensity may be affected by environmental factors and light source aging as the light source is used. At this point, the real-time feedback mechanism plays a crucial role, automatically detecting and correcting deviations in light intensity. Through continuous adjustments, the light intensity of each zone can always be maintained within a stable range.

[0032] In this embodiment, the complexity of manual operation is avoided by using automated adjustment, the testing process is simplified, and the accuracy and consistency of the test are improved.

[0033] This invention significantly improves the uniformity and stability of the light source by dividing the light source 100 into multiple independent zoned light-emitting units 100B and using independent driving units to precisely control the illumination intensity of each zoned light-emitting unit 100B. Combined with a real-time feedback mechanism, this invention can dynamically correct deviations in light source intensity, ensuring long-term consistency and stability of the light source during testing. This method not only solves the testing error problem caused by light source non-uniformity in existing technologies but also simplifies the operation process and reduces human error through automated adjustment. Through zoned control and precise adjustment of the light source, this invention can meet the high-efficiency requirements of multi-site simultaneous testing and large-scale mass production testing, significantly improving the accuracy and reliability of testing. In summary, this invention provides an efficient, accurate, and reliable solution for mass production testing of image sensors and has broad application prospects.

[0034] It should be understood that the term "and / or" in this document is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this document indicates that the preceding and following related objects are in an "or" relationship. "Multiple" in the embodiments of this application refers to two or more. The descriptions such as "first," "second," etc., appearing in the embodiments of this application are only for illustration and to distinguish the described objects; they have no order and do not represent a special limitation on the number of devices in the embodiments of this application, nor do they constitute any limitation on the embodiments of this application.

[0035] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A partitioned light source for CP testing of image sensors, characterized in that, The light source includes: a light-emitting unit for emitting light; a partition control unit for dividing the light source into multiple independent light source partitions according to the distribution coordinates of each Site on the image sensor chip; each light source partition is equipped with an independent driving unit for independently controlling the light intensity of that partition.

2. The light source as described in claim 1, wherein, The light-emitting unit is an LED light source or a laser light source.

3. The light source as described in claim 1, wherein, The partition control unit precisely divides the light source into partitions according to the layout of the image sensor chip, and adjusts the light intensity of each partition to a predetermined value.

4. The light source as described in claim 1, wherein, The drive unit includes a feedback control system for adjusting the light intensity in real time.

5. The light source as described in claim 1, wherein, The light-emitting unit and the driving unit work together to ensure that the light intensity of the light source is evenly distributed in each zone.

6. A method for controlling a light source as described in any one of claims 1-5, characterized in that, Includes the following steps: Step 1: Based on the distribution coordinates of each Site on the image sensor chip, divide the light source into multiple independent light source zones; Step 2: Acquire initial illumination data for each zone using the image sensor chip; Step 3: Based on the collected illumination data, establish a calibration model for the luminous parameters of each zone, and calibrate the luminous intensity of the light source in each zone according to the model; Step 4: Adjust the light intensity of each zone using an independent drive unit to ensure that the light source is evenly distributed in each zone.

7. The light source control method as described in claim 6, wherein, In step 3, the calibration model, taking into account the requirement of ≥99% site-to-site consistency, calculates and adjusts the required light source intensity for each zone.

8. The light source control method as described in claim 6, wherein, The method further includes introducing a real-time feedback mechanism during the adjustment of the light source intensity to dynamically correct the light source intensity deviation.

9. The light source control method as described in claim 6, wherein, The real-time feedback mechanism monitors the deviation between the actual luminous intensity of the light source and the set value, and adjusts the light source intensity in real time to ensure the uniformity of illumination in each zone.

10. The light source control method as described in claim 6, wherein, The method described is applicable to mass production testing of CIS chips, improving testing efficiency and reducing testing errors.

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