Method and system for testing frequency response curve of photoelectric detector

Abstract

The invention provides a photoelectric detector frequency response curve test method and system, and the method comprises the steps: controlling a laser beam emitted by a laser light source to change in a preset frequency range through a second lock-in amplifier; controlling the laser beam to pass through a spectrometer to obtain a first beam and a second beam; the first light beam sequentially passes through an optical power meter and a first lock-in amplifier, the second light beam sequentially passes through a photoelectric detector and a second lock-in amplifier, the optical power meter is used for outputting optical power of the first light beam, and the photoelectric detector is used for outputting light current of the second light beam; obtaining a relation curve of the frequency output by the first lock-in amplifier and the optical power, and obtaining a relation curve of the frequency output by the second lock-in amplifier and the light current; the relation curve of the frequency and the optical power and the relation curve of the frequency and the light current are input into the computer for normalization processing, the frequency response curve of the photoelectric detector is obtained, the influence of the optical power on the result is eliminated, and the accuracy of the frequency response curve can be improved.

Description

Technical Field

[0001] The present application relates to the field of photoelectric detectors, and in particular to a method and system for testing a frequency response curve of a photoelectric detector. Background Art

[0002] When testing the frequency response curve of a semiconductor photodetector, the light source is usually used to generate light signals of different frequencies, and then the response of the light signal is received and measured by the photodetector. By measuring the output signal intensity of the photodetector at different frequencies, its frequency response curve can be obtained, thereby understanding the response characteristics of the photodetector at different frequencies. However, the existing methods are not universal due to their complex systems, low detection efficiency, high detection costs, and inaccurate detection. Providing a suitable test method for the frequency response curve of a photodetector has become a technical problem that urgently needs to be solved. Summary of the invention

[0003] In view of this, the purpose of this application is to provide a method and system for testing the frequency response curve of a photodetector. The frequency response curve obtained after normalization eliminates the influence of optical power on the result, which can improve the accuracy of the frequency response curve. The measurement method is relatively simple and easy to operate. The specific scheme is as follows:

[0004] On the one hand, the present application provides a method for testing a frequency response curve of a photodetector, which is applied to a test system, wherein the test system includes a laser light source, a spectrometer, an optical power meter, a photodetector, a first lock-in amplifier, a second lock-in amplifier, and a computer, and the method includes:

[0005] Controlling the laser beam emitted by the laser light source to change within a preset frequency range through the second lock-in amplifier;

[0006] Control the laser beam to pass through the spectrometer to obtain a first beam and a second beam; the first beam passes through the optical power meter and the first phase-locked amplifier in sequence, and the second beam passes through the photodetector and the second phase-locked amplifier in sequence, the optical power meter is used to output the optical power of the first beam, and the photodetector is used to output the photocurrent of the second beam;

[0007] Obtaining a relationship curve between the frequency and optical power output by the first lock-in amplifier, and obtaining a relationship curve between the frequency and photocurrent output by the second lock-in amplifier;

[0008] The relationship curve between the frequency and the optical power, and the relationship curve between the frequency and the photocurrent are input into the computer for normalization processing to obtain the frequency response curve of the photodetector.

[0009] Optionally, the frequency response curve is a relationship curve between frequency and photocurrent per unit optical power, and the relationship curve between frequency and optical power and the relationship curve between frequency and photocurrent are input into the computer for normalization processing to obtain the frequency response curve of the photodetector, including:

[0010] The photocurrent in the relationship curve between frequency and photocurrent is divided by the light power in the relationship curve between frequency and light power to obtain the relationship curve between frequency and photocurrent per unit light power.

[0011] Optionally, in the test system, the first lock-in amplifier is connected to the second lock-in amplifier, and obtaining a relationship curve between a frequency and an optical power output by the first lock-in amplifier includes:

[0012] Get the first reference frequency of the input;

[0013] The second lock-in amplifier sends a second reference frequency determined based on the first reference frequency to the first lock-in amplifier;

[0014] A relationship curve between the frequency and the optical power determined by the first lock-in amplifier based on the second reference frequency is obtained.

[0015] Optionally, the preset frequency range is 0-100KHZ.

[0016] In another aspect, an embodiment of the present application further provides a system for testing a frequency response curve of a photodetector, the system comprising:

[0017] A laser light source, used for emitting a laser beam;

[0018] A spectrometer, used for splitting the laser beam into a first beam and a second beam;

[0019] An optical power meter, used to measure the optical power of the first light beam;

[0020] a photodetector, configured to measure a photocurrent of the second light beam;

[0021] A first lock-in amplifier connected to the optical power meter, used for outputting a relationship curve between frequency and optical power;

[0022] A second lock-in amplifier connected to the laser light source, used to control the laser light beam to change within a preset frequency range, and the second lock-in amplifier is also connected to the photodetector, used to output a relationship curve between frequency and photocurrent;

[0023] A computer connected to both the first lock-in amplifier and the second lock-in amplifier is used to normalize the relationship curve between the frequency and the optical power and the relationship curve between the frequency and the photocurrent to obtain the frequency response curve of the photodetector.

[0024] Optionally, the frequency response curve is a curve of relationship between frequency and photocurrent per unit optical power, and the computer is used for:

[0025] The photocurrent in the relationship curve between frequency and photocurrent is divided by the light power in the relationship curve between frequency and light power to obtain the relationship curve between frequency and photocurrent per unit light power.

[0026] Optionally, the first lock-in amplifier and the second lock-in amplifier are connected;

[0027] The second lock-in amplifier is used for sending a second reference frequency determined based on the input first reference frequency to the first lock-in amplifier;

[0028] The first lock-in amplifier is used to determine a relationship curve between the frequency and the optical power based on the second reference frequency.

[0029] Optionally, the preset frequency range is 0-100KHZ.

[0030] In another aspect, an embodiment of the present application provides a computer device, the computer device comprising a processor and a memory:

[0031] The memory is used to store program code and transmit the program code to the processor;

[0032] The processor is configured to execute the method described above according to the instructions in the program code.

[0033] On the other hand, an embodiment of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium is used to store a computer program, and the computer program is used to execute the method described in the above aspects.

[0034] The embodiment of the present application provides a method and system for testing the frequency response curve of a photodetector. The method is applied to a test system, and the test system includes a laser light source, a spectrometer, an optical power meter, a photodetector, a first phase-locked amplifier, a second phase-locked amplifier, and a computer. Through the second phase-locked amplifier, the laser light beam emitted by the laser light source is controlled to change within a preset frequency range; the laser light beam is controlled to pass through the spectrometer to obtain a first light beam and a second light beam; the first light beam passes through the optical power meter and the first phase-locked amplifier in sequence, and the second light beam passes through the photodetector and the second phase-locked amplifier in sequence, the optical power meter is used to output the optical power of the first light beam, and the photodetector is used to output the photocurrent of the second light beam; the relationship curve between the frequency and the optical power output by the first phase-locked amplifier is obtained, and the relationship curve between the frequency and the photocurrent output by the second phase-locked amplifier is obtained; the relationship curve between the frequency and the optical power, and the relationship curve between the frequency and the photocurrent are input into the computer for normalization processing to obtain the frequency response curve of the photodetector. It can be seen that in the frequency response curve obtained after the normalization processing, the influence of the optical power on the result is eliminated, the accuracy of the frequency response curve can be improved, and the measurement method is relatively simple and easy to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present application 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 some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0036] Figure 1 A schematic diagram showing a flow chart of a method for testing a frequency response curve of a photodetector provided in an embodiment of the present application;

[0037] Figure 2 A schematic diagram of a photodetector frequency response curve testing system provided in an embodiment of the present application is shown;

[0038] Figure 3 A schematic diagram of a process flow of a testing method provided in an embodiment of the present application is shown;

[0039] Figure 4 A structural diagram of a computer device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0040] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below with reference to the accompanying drawings.

[0041] In the following description, many specific details are set forth to facilitate a full understanding of the present application, but the present application may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0042] For ease of understanding, a method and system for testing a frequency response curve of a photodetector provided in an embodiment of the present application are described in detail below with reference to the accompanying drawings.

[0043] refer to Figure 1 As shown, it is a schematic flow chart of a method for testing a frequency response curve of a photodetector provided in an embodiment of the present application. The method may include the following steps S101-S104.

[0044] This test method can be applied to the test system, refer to Figure 2 As shown, it is a schematic diagram of a test system for a photodetector frequency response curve provided in an embodiment of the present application. The test system may include a laser light source 1, a spectrometer 2, an optical power meter 3, a photodetector 4, a first phase-locked amplifier 5, a second phase-locked amplifier 6 and a computer 7.

[0045] S101, controlling the laser beam emitted by the laser light source to change within a preset frequency range through a second phase-locked amplifier.

[0046] The second lock-in amplifier 6 can be connected to the laser light source 1, and the laser light source 1 can emit a laser beam. The second lock-in amplifier 6 can modulate the frequency of the laser beam to change it within a preset frequency range to obtain optical signals of different frequencies, so as to measure the frequency response curve of the photodetector 4 within the preset frequency range to meet the response range requirements of the photodetector 4 to different frequencies. As an example, the preset frequency range can be 0-100KHZ, that is, the second lock-in amplifier 6 can be modulated within the range of 0-100KHz.

[0047] That is to say, under the action of the second lock-in amplifier 6, the frequency of the laser beam can be obtained. In addition, the second lock-in amplifier 6 can also filter out interference from other signals to achieve precise control of the frequency of the optical signal.

[0048] S102, controlling the laser beam to pass through a spectrometer to obtain a first beam and a second beam.

[0049] In the embodiment of the present application, the laser beam can enter the spectrometer 2, and the spectrometer 2 is used for splitting to obtain a first beam and a second beam. The first beam can sequentially pass through the optical power meter 3 and the first phase-locked amplifier 5, and the second beam can sequentially pass through the photodetector 4 and the second phase-locked amplifier 6. The optical power meter 3 can be used to output the optical power of the first beam, and the photodetector 4 can be used to output the photocurrent of the second beam.

[0050] That is to say, the optical power meter 3 can measure the optical power of the laser beam, and the photodetector 4 can measure the photocurrent of the laser beam. That is to say, for a laser beam at a certain frequency, the optical power and the photocurrent can be measured simultaneously, so that the influence of the optical power on the photocurrent can be eliminated later.

[0051] S103, obtaining a relationship curve between the frequency and the optical power output by the first lock-in amplifier, and obtaining a relationship curve between the frequency and the photocurrent output by the second lock-in amplifier.

[0052] In the embodiment of the present application, after the first light beam passes through the optical power meter 3, it is converted into a signal and transmitted to the first phase-locked amplifier 5. The first phase-locked amplifier 5 can provide a reference frequency for the signal to filter out signals of other frequencies and only retain the signal at the current frequency, thereby improving the signal accuracy. The first phase-locked amplifier 5 can output a relationship curve between the frequency and the optical power of the first light beam, and the relationship curve is represented by the frequency as the horizontal coordinate and the optical power as the vertical coordinate.

[0053] After passing through the spectrometer 2, the second light beam is incident on the photodetector 4. The photodetector 4 can convert the optical signal into an electrical signal, and then transmit the electrical signal to the second phase-locked amplifier 6. The second phase-locked amplifier 6 can also provide a reference frequency for the electrical signal to filter out signals of other frequencies and only retain the signal at the current frequency to improve the signal accuracy. Thus, the second phase-locked amplifier 6 can output a relationship curve between frequency and photocurrent, which has frequency as the horizontal coordinate and photocurrent as the vertical coordinate.

[0054] S104, inputting the relationship curve between frequency and optical power, and the relationship curve between frequency and photocurrent into a computer for normalization processing to obtain a frequency response curve of the photodetector.

[0055] In the embodiment of the present application, the computer 7 can calculate and process these two relationship curves. For the same frequency, the relationship curve between frequency and light power has the light power corresponding to the frequency, and the relationship curve between frequency and photocurrent has the photocurrent corresponding to the frequency. The light power and photocurrent can be normalized to eliminate the influence of the light power on the photocurrent, thereby eliminating the power change caused by frequency modulation, so that at different frequencies, the photocurrent size corresponding to the same light power is obtained, thereby obtaining the frequency response curve of the photodetector 4.

[0056] That is to say, in the frequency response curve, the photocurrent as the vertical coordinate eliminates the influence of power on the photocurrent, and can more clearly reflect the influence of different frequencies on the photocurrent, thereby improving the accuracy of the photocurrent and the accuracy of the frequency response curve. In addition, the two phase-locked amplifiers lock the signal frequencies of the two optical paths respectively to filter out the interference of noise signals, which greatly improves the accuracy of signal detection. The measurement method is relatively simple and easy to operate.

[0057] In one possible implementation, the frequency response curve is a curve of the relationship between frequency and photocurrent per unit optical power. S104 may be specifically to divide the photocurrent in the curve of the relationship between frequency and photocurrent by the optical power in the curve of the relationship between frequency and optical power to obtain the curve of the relationship between frequency and photocurrent per unit optical power.

[0058] Specifically, the photocurrent per unit optical power can be understood as the size of the photocurrent under unit optical power. In this way, the frequency response curve of the photodetector 4 is the relationship curve between frequency and photocurrent per unit optical power. At each frequency, there is a corresponding photocurrent and optical power. The photocurrent is divided by the optical power to obtain the photocurrent under unit optical power. In this way, the photocurrents at all frequencies eliminate the influence of optical power on them. The photocurrents at different frequencies are compared in the same dimension, that is, the normalized photocurrents are compared to obtain the frequency response curve. In this way, the influence of optical power on the photocurrent can be more completely eliminated, thereby improving the accuracy of the frequency response curve.

[0059] In a possible implementation, in the test system, the first lock-in amplifier 5 and the second lock-in amplifier 6 can be connected. Figure 2 As shown by the dotted line in the middle, obtaining the relationship curve between the frequency and optical power output by the first phase-locked amplifier 5 can be specifically as follows: obtaining the input first reference frequency; the second phase-locked amplifier 6 sends the second reference frequency determined based on the first reference frequency to the first phase-locked amplifier 5; obtaining the relationship curve between the frequency and optical power determined by the first phase-locked amplifier 5 based on the second reference frequency.

[0060] Specifically, the tester can input the first reference frequency to the second phase-locked amplifier 6. The first reference frequency can be, for example, 50HZ. Since the internal structure of the second phase-locked amplifier 6 is relatively complex, the second phase-locked amplifier 6 may actually determine the second reference frequency, for example, 55HZ. The second reference frequency will be used as the reference frequency in the future to filter out signals of other frequencies and only retain the signal at the second reference frequency, thereby improving signal accuracy and outputting the relationship curve between frequency and photocurrent. Similarly, the tester can also input a reference frequency to the first phase-locked amplifier 5. According to the reference frequency, another reference frequency is determined inside the first phase-locked amplifier 5 to filter the signal and output the relationship curve between frequency and optical power.

[0061] In order to avoid the inconsistency of the frequencies used to filter signals inside the two phase-locked amplifiers, resulting in the two relationship curves being unable to correspond to the same frequency, the two phase-locked amplifiers can be connected. In this way, the second reference frequency determined inside the second phase-locked amplifier 6 can be sent to the first phase-locked amplifier 5. Both phase-locked amplifiers can use the second reference frequency as the reference frequency to filter signals. Both relationship curves are determined based on the second reference frequency, so that the photocurrent and optical power can correspond to the same frequency, ensuring that the frequency of the optical signal after splitting remains the same, thereby improving the accuracy and consistency of the two relationship curves.

[0062] refer to Figure 3 As shown, it is a schematic diagram of the process of a test method provided in an embodiment of the present application. The laser light source 1 is frequency modulated by the second phase-locked amplifier 6 to meet the requirements of the photodetector 4 for different frequency response ranges. The optical signal can be divided into two identical parts by using the spectrometer 2 and enter the two optical paths of the system respectively. The power change of the optical signal is detected by the optical power meter 3. At the same time, the optical power meter 3 is connected to the first phase-locked amplifier 5. The first phase-locked amplifier 5 provides a reference frequency, filters out the influence of other frequency signals, and obtains the relationship between frequency and optical power.

[0063] The photodetector 4 is used to receive light signals of different frequencies and convert the light signals into electrical signals for the next step of signal acquisition. The second phase-locked amplifier 6 is used to receive the electrical signal output by the photodetector 4, obtain the frequency-photocurrent relationship, and input it to the computer 7. The computer 7 detects and processes the signal, normalizes the frequency-photocurrent relationship by analyzing and processing the input signal and the output signal, and obtains the frequency response curve corresponding to the photodetector 4.

[0064] The embodiment of the present application provides a method for testing the frequency response curve of a photodetector, which is applied to a test system, wherein the test system includes a laser light source, a spectrometer, an optical power meter, a photodetector, a first phase-locked amplifier, a second phase-locked amplifier, and a computer. Through the second phase-locked amplifier, the laser light beam emitted by the laser light source is controlled to change within a preset frequency range; the laser light beam is controlled to pass through the spectrometer to obtain a first light beam and a second light beam; the first light beam passes through the optical power meter and the first phase-locked amplifier in sequence, and the second light beam passes through the photodetector and the second phase-locked amplifier in sequence, the optical power meter is used to output the optical power of the first light beam, and the photodetector is used to output the photocurrent of the second light beam; the relationship curve between the frequency and the optical power output by the first phase-locked amplifier is obtained, and the relationship curve between the frequency and the photocurrent output by the second phase-locked amplifier is obtained; the relationship curve between the frequency and the optical power, and the relationship curve between the frequency and the photocurrent are input into the computer for normalization processing to obtain the frequency response curve of the photodetector. It can be seen that in the frequency response curve obtained after the normalization processing, the influence of the optical power on the result is eliminated, the accuracy of the frequency response curve can be improved, and the measurement method is relatively simple and easy to operate.

[0065] Based on the above test method for the frequency response curve of the photoelectric detector, the embodiment of the present application also provides a test system for the frequency response curve of the photoelectric detector, referring to Figure 2 As shown, the test system includes:

[0066] A laser light source 1, used for emitting a laser beam;

[0067] A spectrometer 2, used for splitting the laser beam into a first beam and a second beam;

[0068] An optical power meter 3, used for measuring the optical power of the first light beam;

[0069] A photodetector 4, used for measuring the photocurrent of the second light beam;

[0070] A first lock-in amplifier 5 connected to the optical power meter, used for outputting a relationship curve between frequency and optical power;

[0071] A second lock-in amplifier 6 connected to the laser light source is used to control the laser light beam to change within a preset frequency range. The second lock-in amplifier is also connected to the photodetector to output a relationship curve between frequency and photocurrent;

[0072] The computer 7 connected to the first lock-in amplifier 5 and the second lock-in amplifier 6 is used to normalize the relationship curve between frequency and optical power and the relationship curve between frequency and photocurrent to obtain the frequency response curve of the photodetector.

[0073] Specifically, the frequency response curve is a curve of the relationship between frequency and photocurrent per unit optical power. The computer is used to:

[0074] The photocurrent in the relationship curve between frequency and photocurrent is divided by the optical power in the relationship curve between frequency and optical power to obtain the relationship curve between frequency and photocurrent per unit optical power.

[0075] Specifically, the first lock-in amplifier is connected to the second lock-in amplifier;

[0076] The second lock-in amplifier is used for sending the second reference frequency determined based on the input first reference frequency to the first lock-in amplifier;

[0077] The first phase-locked amplifier is used to determine a relationship curve between frequency and optical power based on the second reference frequency.

[0078] Specifically, the preset frequency range is 0-100KHZ.

[0079] The embodiment of the present application provides a test system for the frequency response curve of a photodetector, the test system includes a laser light source, a spectrometer, an optical power meter, a photodetector, a first phase-locked amplifier, a second phase-locked amplifier and a computer, through the second phase-locked amplifier, the laser light beam emitted by the laser light source is controlled to change within a preset frequency range; the laser light beam is controlled to pass through the spectrometer to obtain a first light beam and a second light beam; the first light beam passes through the optical power meter and the first phase-locked amplifier in sequence, and the second light beam passes through the photodetector and the second phase-locked amplifier in sequence, the optical power meter is used to output the optical power of the first light beam, and the photodetector is used to output the photocurrent of the second light beam; the relationship curve between the frequency and the optical power output by the first phase-locked amplifier is obtained, and the relationship curve between the frequency and the optical power output by the second phase-locked amplifier is obtained; the relationship curve between the frequency and the optical power, and the relationship curve between the frequency and the photocurrent are input into the computer for normalization processing to obtain the frequency response curve of the photodetector. It can be seen that in the frequency response curve obtained after the normalization processing, the influence of the optical power on the result is eliminated, the accuracy of the frequency response curve can be improved, and the measurement method is relatively simple and easy to operate.

[0080] In another aspect, the present application provides a computer device, referring to Figure 4 , which is a structural diagram of a computer device provided in an embodiment of the present application, wherein the computer device includes a processor 310 and a memory 320:

[0081] The memory 320 is used to store program codes and transmit the program codes to the processor 310;

[0082] The processor 310 is used to execute the method provided in the above embodiment according to the instructions in the program code.

[0083] The computer device may include a terminal device or a server, and the aforementioned apparatus may be configured in the computer device.

[0084] On the other hand, an embodiment of the present application further provides a storage medium, wherein the storage medium is used to store a computer program, and the computer program is used to execute the method provided by the above embodiment.

[0085] A person skilled in the art can understand that all or part of the steps of implementing the above method embodiment can be completed by program instruction hardware, and the above program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above method embodiment; and the above storage medium can be at least one of the following media: read-only memory (English: Read-only Memory, abbreviated: ROM), RAM, magnetic disk or optical disk, etc. Various media that can store program codes.

[0086] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0087] The above is only a preferred implementation of the present application. Although the present application has been disclosed as a preferred embodiment, it is not intended to limit the present application. Any technician familiar with the art can use the above disclosed methods and technical contents to make many possible changes and modifications to the technical solution of the present application without departing from the scope of the technical solution of the present application, or modify it into an equivalent embodiment of equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application still falls within the scope of protection of the technical solution of the present application.

Claims

1. A method for testing a frequency response curve of a photodetector, characterized in that: Applied to a test system, the test system includes a laser light source, a spectrometer, an optical power meter, a photodetector, a first lock-in amplifier, a second lock-in amplifier and a computer, and the method includes: Controlling the laser beam emitted by the laser light source to change within a preset frequency range through the second lock-in amplifier; Control the laser beam to pass through the spectrometer to obtain a first beam and a second beam; the first beam passes through the optical power meter and the first phase-locked amplifier in sequence, and the second beam passes through the photodetector and the second phase-locked amplifier in sequence, the optical power meter is used to output the optical power of the first beam, and the photodetector is used to output the photocurrent of the second beam; Obtaining a relationship curve between the frequency and optical power output by the first lock-in amplifier, and obtaining a relationship curve between the frequency and photocurrent output by the second lock-in amplifier; The relationship curve between the frequency and the optical power, and the relationship curve between the frequency and the photocurrent are input into the computer for normalization processing to obtain the frequency response curve of the photodetector.

2. The method according to claim 1, characterized in that The frequency response curve is a relationship curve between frequency and photocurrent per unit optical power. The relationship curve between frequency and optical power and the relationship curve between frequency and photocurrent are input into the computer for normalization processing to obtain the frequency response curve of the photodetector, including: The photocurrent in the relationship curve between frequency and photocurrent is divided by the light power in the relationship curve between frequency and light power to obtain the relationship curve between frequency and photocurrent per unit light power.

3. The method according to claim 1, characterized in that In the test system, the first lock-in amplifier is connected to the second lock-in amplifier, and obtaining a relationship curve between a frequency and an optical power output by the first lock-in amplifier includes: Get the first reference frequency of the input; The second lock-in amplifier sends a second reference frequency determined based on the first reference frequency to the first lock-in amplifier; A relationship curve between the frequency and the optical power determined by the first lock-in amplifier based on the second reference frequency is obtained.

4. The method according to any one of claims 1 to 3, characterized in that: The preset frequency range is 0-100KHZ.

5. A photoelectric detector frequency response curve testing system, characterized in that: The test system comprises: A laser light source, used for emitting a laser beam; A spectrometer, used for splitting the laser beam into a first beam and a second beam; An optical power meter, used to measure the optical power of the first light beam; a photodetector, configured to measure a photocurrent of the second light beam; A first lock-in amplifier connected to the optical power meter, used for outputting a relationship curve between frequency and optical power; A second lock-in amplifier connected to the laser light source, used to control the laser light beam to change within a preset frequency range, and the second lock-in amplifier is also connected to the photodetector, used to output a relationship curve between frequency and photocurrent; A computer connected to both the first lock-in amplifier and the second lock-in amplifier is used to normalize the relationship curve between the frequency and the optical power and the relationship curve between the frequency and the photocurrent to obtain the frequency response curve of the photodetector.

6. The test system according to claim 5, characterized in that: The frequency response curve is a curve of the relationship between frequency and photocurrent per unit optical power, and the computer is used for: The photocurrent in the relationship curve between frequency and photocurrent is divided by the light power in the relationship curve between frequency and light power to obtain the relationship curve between frequency and photocurrent per unit light power.

7. The test system according to claim 5, characterized in that: The first lock-in amplifier is connected to the second lock-in amplifier; The second lock-in amplifier is used for sending a second reference frequency determined based on the input first reference frequency to the first lock-in amplifier; The first lock-in amplifier is used to determine a relationship curve between the frequency and the optical power based on the second reference frequency.

8. The test system according to any one of claims 5 to 7, characterized in that: The preset frequency range is 0-100KHZ.

9. A computer device, characterized in that: The computer device comprises a processor and a memory: The memory is used to store program code and transmit the program code to the processor; The processor is configured to execute the method according to any one of claims 1 to 4 according to the instructions in the program code.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium is used to store a computer program, and the computer program is used to execute the method according to any one of claims 1 to 4.

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