Consistency detection and verification method for LED array light source of high-throughput living cell imager

Abstract

The invention discloses a consistency detection and verification method for LED array light sources of a high-throughput living cell imager, which is applied to the field of automatic light calibration of a light supplement following control component of a microscopic imaging system of a living cell dynamic detector. Calculating the preset light intensity numerical value brightness of each step, adjusting the duty ratio of the PWM signal to enable the brightness value of the output image to be 1-n times of the preset light intensity numerical value brightness of each step in sequence, recording the corresponding duty ratio value, and completing the consistency inspection of one LED lamp bead; on the basis of the method, consistency inspection of other lamp beads is completed in sequence, and input light intensity and the PWM signal duty ratio of the LED lamp beads at the corresponding position are obtained on the basis of the recorded duty ratio during normal operation of the imager and used for consistency imaging. According to the invention, the problem of consistency error of each LED lamp bead in the LED array light source is improved and solved.

Description

Technical Field

[0001] The invention relates to the field of automatic light calibration of a fill light follower control component of a microscopic imaging system of a living cell dynamic detector, and in particular to a consistency detection and calibration method for an LED array light source of a high-throughput living cell imager. Background Art

[0002] Live cell imaging detection technology is a commonly used technology in the field of biology and biomedicine, which is used to observe and record the structure, function and interaction of cells at the level of living cells. This technology can obtain images and data in real time in the state of living cells, providing a powerful tool for studying cell biology, cell signal transduction, drug development and other fields. As the object of research, it is necessary to maintain a stable physiological state, reduce vibration, phototoxicity and light pollution during the detection process. The stage and the living cell specimen on it do not move, the objective lens and the imaging module are integrated on a mobile platform, and the mobile platform moves the objective lens and the imaging module to the specimen area to be observed before imaging. High-throughput live cell imagers have emerged. Some manufacturers' high-throughput live cell imagers use LED array light sources as their light sources, and synchronize the control system and the objective lens movement and imaging: the objective lens moves to the area to be imaged, and when imaging begins, the control system controls the LED in the area in the LED array to light up, and after imaging is completed, the LED goes out. This light following system solves the problem of phototoxicity of the constant light source to the cells, and solves the problem of vibration and displacement errors caused by the need for a single light source to move synchronously with the objective lens, and also greatly reduces the cost. However, since multiple LEDs are used to form an array, the brightness of each LED has consistency errors. In actual use, even if the light intensity value is the same, the brightness of the pictures presented at different lamp positions will be inconsistent, making the presented pictures unevenly bright and dark. These inconsistent brightness and darkness of living cell images are not only not conducive to the observation of living cells, but also produce great errors when these images are processed by algorithms, resulting in errors in various automatic algorithms based on images, such as automatic calculation of cell fusion, scratch width analysis, and statistics of synaptic length of nerve cells. The reasons for this problem are, on the one hand, the difference in factory consistency of LED lamp beads themselves, on the other hand, the problem of control circuit design, and thirdly, the aging degree of each lamp bead is inconsistent due to the difference in the number of times it is lit and the lighting time after a period of use.

[0003] The traditional solution is to add a constant current drive circuit to the LED lamp, which can only reduce the uneven phenomenon but cannot effectively improve and solve the problem.

[0004] Therefore, how to provide a consistency detection and calibration method for a high-throughput live cell imaging instrument LED array light source that can effectively improve and solve the consistency error problem of each LED lamp bead in the LED array light source is an issue that technical personnel in this field urgently need to solve. Summary of the invention

[0005] In view of this, the present invention proposes a consistency detection and calibration method for an LED array light source of a high-throughput living cell imager.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] A method for consistency detection and verification of LED array light sources for a high-throughput living cell imaging instrument, comprising:

[0008] Step 1: Based on the maximum input light intensity of the host computer and the preset output image brightness value of the maximum input light intensity, calculate the preset light intensity value brightness of each step, and adjust the duty cycle of the PWM signal so that the output image brightness value under the maximum input light intensity reaches 1 to n times of the preset light intensity value brightness of each step in turn, record the corresponding PWM signal duty cycle value, and complete the consistency test of an LED lamp bead; wherein n is the maximum input light intensity;

[0009] Step 2: Based on the LED lamp bead consistency inspection method in step 1, complete the consistency inspection of other LED lamp beads in the LED array light source in turn, and in the normal operation of the high-throughput living cell imager, based on the recorded PWM signal duty cycle value, obtain the input light intensity of the host computer and the PWM signal duty cycle of the LED lamp bead at the corresponding position for consistent imaging of the LED array light source.

[0010] Optionally, in step 2, the camera is moved by an XYZ stepper motor motion control platform to complete the output image acquisition of LED lamp beads at different positions.

[0011] Optionally, in step 2, the input light intensity of the host computer and the PWM signal duty cycle of the LED lamp bead at the corresponding position are obtained based on the recorded duty cycle value of the PWM signal by table lookup method.

[0012] It can be seen from the above technical solutions that, compared with the prior art, the present invention proposes a consistency detection and verification method for the LED array light source of a high-throughput live cell imager. By proposing a software-based LED array light source consistency detection and verification method, that is, by adjusting the PWM signal so that the LED light intensity satisfies the linear relationship between input and output, each lamp bead in the LED array is automatically calibrated in a piecewise linear manner, which effectively improves and solves the consistency error problem of each LED lamp bead in the LED array light source. Experiments show that the present invention can achieve a very high degree of consistency of the LED, and the captured images have almost no brightness difference in the human eye. After verification and optimization, the consistency of the lamp beads can also reach a uniformity of more than ±1%. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0014] Figure 1 It is a schematic diagram of the method flow of the present invention.

[0015] Figure 2 It is a schematic diagram of the brightness condition before the inspection of the present invention.

[0016] Figure 3 This is a schematic diagram of the brightness after verification of the present invention. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] Embodiment 1:

[0019] Embodiment 1 of the present invention discloses a method for detecting and verifying the consistency of an LED array light source of a high-throughput living cell imaging instrument, such as Figure 1 As shown, including:

[0020] Step 1: Based on the maximum input light intensity of the host computer and the preset output image brightness value of the maximum input light intensity, calculate the preset light intensity value brightness of each step, and adjust the duty cycle of the PWM signal so that the output image brightness value under the maximum input light intensity reaches 1 to n times the preset light intensity value brightness of each step in turn, so that the LED light intensity satisfies the linear relationship between input and output, record the corresponding PWM signal duty cycle value, and complete the consistency test of an LED lamp bead; wherein n is the maximum input light intensity.

[0021] Step 2: Based on the LED lamp bead consistency inspection method in step 1, complete the consistency inspection of other LED lamp beads in the LED array light source in turn, and in the normal operation of the high-throughput living cell imager, based on the recorded PWM signal duty cycle value, obtain the input light intensity of the host computer and the PWM signal duty cycle of the LED lamp bead at the corresponding position for consistent imaging of the LED array light source.

[0022] The camera is moved through the XYZ stepper motor motion control platform to complete the output image acquisition of LED lamp beads in different positions.

[0023] The input light intensity of the host computer and the PWM signal duty cycle of the LED lamp bead at the corresponding position are obtained based on the recorded PWM signal duty cycle value through the table lookup method.

[0024] Embodiment 2:

[0025] Embodiment 2 of the present invention discloses a specific application of a method for consistency detection and verification of a high-throughput living cell imaging device LED array light source, as follows:

[0026] Taking the 384LED array configured in the commonly used living cell imager as an example, the maximum input light intensity of the host computer is 100 (the above steps are all 1), and the preset output image brightness value under the maximum input light intensity is 180, then the preset light intensity value brightness of each step is calculated to be 1.8. In order to facilitate the adjustment of the PWM signal under the above-mentioned maximum input light intensity of 100, the duty cycle adjustment range of the PWM signal is set to 0-1000. By adjusting the duty cycle of the PWM signal, the output image brightness value under the input light intensity (the output image brightness value is calculated by using the function provided by opencv after collecting the image) reaches 1 to 100 times the preset light intensity value brightness of each step, that is, the first time the output image brightness value reaches 1.8, the second time the output image brightness value reaches 1.8×2, the kth time the output image brightness value reaches 1.8×k, until the hundredth time the output image brightness value reaches 1.8×100, record the corresponding PWM signal duty cycle values ​​100 times, and complete the consistency test of an LED lamp bead.

[0027] The camera is moved by the XYZ stepper motor motion control platform to complete the output image acquisition of LED lamp beads at different positions, so as to conduct consistency inspection of other LED lamp beads. A total of 384 LED lamp beads need to be inspected. The verification results are stored in the file. When the instrument is operating normally, the input light intensity of the host computer and the PWM signal duty cycle of the LED lamp beads at the corresponding position are obtained by the table lookup method, and then the data is sent to the LED array through the communication interface for consistent imaging of the LED array light source.

[0028] The brightness before the test and the brightness after the test are as follows: Figure 2 and Figure 3 It can be seen that the present invention can achieve a high degree of consistency of LEDs, and the captured images have almost no brightness difference in the human eye. After verification and optimization, the consistency of the lamp beads can also reach a uniformity of more than ±1%.

[0029] The embodiment of the present invention discloses a consistency detection and verification method for a high-throughput live cell imaging instrument LED array light source. By proposing a software-based LED array light source consistency detection and verification method, that is, by adjusting the PWM signal so that the LED light intensity satisfies the linear relationship between input and output, each lamp bead in the LED array is automatically calibrated in a piecewise linear manner, thereby effectively improving and solving the consistency error problem of each LED lamp bead in the LED array light source. Experiments show that the present invention can achieve a very high degree of consistency of LEDs, and the captured images have almost no brightness difference in the human eye. After verification and optimization, the consistency of the lamp beads can also reach a uniformity of more than ±1%.

[0030] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0031] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for consistency detection and verification of LED array light sources for high-throughput living cell imaging, characterized in that: include: Step 1: Based on the maximum input light intensity of the host computer and the preset output image brightness value of the maximum input light intensity, calculate the preset light intensity value brightness of each step, and adjust the duty cycle of the PWM signal so that the output image brightness value under the maximum input light intensity reaches 1 to n times of the preset light intensity value brightness of each step in turn, record the corresponding duty cycle value of the PWM signal, and complete the consistency test of an LED lamp bead; wherein n is the maximum input light intensity; Step 2: Based on the LED lamp bead consistency inspection method in step 1, complete the consistency inspection of other LED lamp beads in the LED array light source in turn, and in the normal operation of the high-throughput living cell imager, based on the recorded PWM signal duty cycle value, obtain the input light intensity of the host computer and the PWM signal duty cycle of the LED lamp bead at the corresponding position for consistent imaging of the LED array light source.

2. The method for consistency detection and verification of a high-throughput living cell imaging LED array light source according to claim 1, characterized in that: In step 2, the camera is moved by the XYZ stepper motor motion control platform to complete the output image acquisition of LED lamp beads at different positions.

3. The method for consistency detection and verification of a high-throughput living cell imaging LED array light source according to claim 1, characterized in that: In step 2, the input light intensity of the host computer and the PWM signal duty cycle of the LED lamp bead at the corresponding position are obtained based on the recorded duty cycle value of the PWM signal by using a table lookup method.

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