A method and apparatus for testing the impulse response of a photodetector

Abstract

The application discloses a kind of pulse response degree testing devices of photoelectric detector, including pulsed light source, optical attenuator, fiber optic power meter, auxiliary photoelectric detector, measured photoelectric detector, oscilloscope and control and data processing module, also provide a kind of pulse response degree testing method of photoelectric detector, utilize the above device setting the center frequency and pulse width of pulsed light source, after optical pulse signal is input fiber optic power meter, auxiliary photoelectric detector and measured photoelectric detector after optical attenuator, the peak optical power of optical pulse excitation source and the pulse response degree of measured photoelectric detector are recorded in turn calculation, and the pulse response degree of measured photoelectric detector under other pulse width can be repeatedly obtained. By the above-mentioned mode, it is solved that the testing method of traditional photoelectric detector pulse response degree all needs a known pulse response degree high-speed photoelectric detector, the problem that the configuration requirement of system is higher, and system is relatively complex.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of photoelectric detector, in particular to a kind of photoelectric detector's impulse response degree test method and device. BACKGROUND

[0002] Photoelectric detector is a kind of basic device for converting optical signal into electrical signal, and its key parameter is response degree, which characterizes the ability of photoelectric conversion, and can be divided into spectral response, frequency response and impulse response.In laser communication, laser monitoring and guidance, laser ranging, laser radar and laser warning system, photoelectric detector is used to respond to weak optical pulse signal, which is equivalent to the eye of the whole system, and impulse response degree is a crucial parameter index, which determines the sensitivity, dynamic range and accuracy of the whole system, and also affects the development and production of photoelectric detector, system design and optimization.Therefore, the impulse response degree of photoelectric detector must be accurately tested.

[0003] Most of the traditional photoelectric detector response degree test methods are for continuous light excitation source, and few are for optical pulse excitation source.Some scholars have proposed an optical system based on double light path replacement method, which uses a standard photoelectric detector, an auxiliary photoelectric detector and a measured photoelectric detector to form a pulse response degree test equation set, and finally calculates the pulse response degree relationship between the measured photoelectric detector and the standard photoelectric detector to obtain the pulse response degree of the measured photoelectric detector.This method can effectively avoid the influence of the fluctuation of light source output optical power and the measurement error of optical splitter, but in order to obtain the pulse response degree of the measured photoelectric detector, an auxiliary photoelectric detector and a standard photoelectric detector with known pulse response degree are needed, which greatly improves the configuration requirements of the system and the operation is more complex.Some scholars have also proposed a portable quadrant detector pulse response rate parameter calibration device, which can use the same pulse light source of the corresponding measuring device as the excitation light source to solve the nonlinear difference in value between the measuring device and the calibration device caused by the inconsistency of the excitation signal pulse width, but in order to obtain the peak power of the optical pulse excitation source, a high-speed photoelectric detector with known pulse response degree is still needed, and the test result of the measured photoelectric detector will also be affected by the response degree of the photoelectric detector.Therefore, there is a great need for a method that is simple in system and does not need known standard or auxiliary photoelectric detector pulse response degree to obtain the pulse response degree of the measured photoelectric detector. SUMMARY

[0004] In view of the above deficiencies in the prior art, the present application provides a photoelectric detector impulse response degree test method and device.

[0005] In order to achieve the above-mentioned application purposes, the technical scheme adopted by the present application is:

[0006] A kind of pulse response degree testing device of photoelectric detector, including pulse light source, optical attenuator, fiber optical power meter, auxiliary photoelectric detector, measured photoelectric detector, oscilloscope and control and data processing module;

[0007] The pulse light source is connected with optical attenuator, for generating the optical pulse excitation source of measured photoelectric detector;The optical attenuator is sequentially connected with fiber optical power meter, auxiliary photoelectric detector, measured photoelectric detector with light, for obtaining the parameter of optical pulse excitation source and the electrical signal generated by measured photoelectric detector;The auxiliary photoelectric detector, measured photoelectric detector are simultaneously connected with oscilloscope with electricity, for analyzing the electrical signal after photoelectric conversion;The control and data processing module is sequentially connected with pulse light source, fiber optical power meter, oscilloscope with data, for setting the parameter of pulse light source, recording and processing the data obtained by measurement.

[0008] Further, the pulse light source is passive mode-locked laser or supercontinuum light source or comb spectrum coherent light source.

[0009] Further, the pulse width of the pulse light source is (10-200) ns adjustable.

[0010] A kind of pulse response degree testing method of photoelectric detector, comprising the following steps:

[0011] S1: the center frequency and pulse width of pulse light source are set using control and data processing module;

[0012] S2: pulse light source emits optical pulse signal, and input into optical attenuator through fiber active connector to carry out certain attenuation, to avoid that the auxiliary photoelectric detector or measured photoelectric detector is saturated by too large optical power;

[0013] S3: the attenuated optical pulse signal is first input into fiber optical power meter, to obtain the average optical power of optical pulse excitation source, and record P a As control and data processing module;

[0014] S4: optical pulse excitation source is input into auxiliary photoelectric detector, and the electrical signal obtained after photoelectric conversion is input into oscilloscope, to obtain the period and pulse width of optical pulse excitation source, and record T and τ as control and data processing module;

[0015] S5: the peak optical power of optical pulse excitation source is calculated using control and data processing module;

[0016] S6: finally, optical pulse excitation source is input into measured photoelectric detector, and the electrical signal obtained after photoelectric conversion is collected by oscilloscope, to obtain the peak voltage of measured electrical signal, and record V m As control and data processing module.

[0017] S7: calculating the pulse response of the measured photoelectric detector by the control and data processing module;

[0018] S8: changing the pulse width of the pulse light source by the control and data processing module, repeating steps S2-S7, so as to obtain the pulse response of the measured photoelectric detector under other pulse widths.

[0019] Further, the calculation method of the peak optical power of the optical pulse excitation source in S5 is:

[0020]

[0021] Wherein, P p is the peak optical power of the optical pulse excitation source, P a is the average optical power of the optical pulse excitation source, T is the period of the optical pulse excitation source, and τ is the pulse width.

[0022] Further, the specific calculation method of the pulse response in S7 is:

[0023]

[0024] Wherein, P p is the peak optical power of the optical pulse excitation source, P a is the average optical power of the optical pulse excitation source, T is the period of the optical pulse excitation source, τ is the pulse width, and V m is the peak voltage of the measured electrical signal.

[0025] The present application has the following beneficial effects:

[0026] The method has a relatively simple structure, and only one auxiliary photoelectric detector is needed to measure the pulse width and period of the optical pulse excitation source. Compared with the first kind of double optical path replacement method, one photoelectric detector is saved, and compared with the second kind of portable quadrant detector pulse response rate parameter calibration device, the test can be realized without the pulse response of the known auxiliary photoelectric detector, which reduces the configuration requirements of the system and eliminates the influence of the pulse response of the auxiliary photoelectric detector on the test results. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 is a photoelectric detector pulse response test device diagram of the present application.

[0028] Figure 2 is a photoelectric detector pulse response test method flow chart of the present application. DETAILED DESCRIPTION

[0029] The specific embodiments of the present application are described below to facilitate the understanding of the present application for those skilled in the art, but it should be clear that the present application is not limited to the scope of the specific embodiments, and for those skilled in the art, it is obvious that various changes are within the spirit and scope of the present application defined and determined by the appended claims, and all the inventions utilizing the concept of the present application are within the scope of protection.

[0030] A pulse response test device for a photoelectric detector, as shown in Figure 1 , comprising a pulsed light source 1, an optical attenuator 2, a fiber optical power meter 3, an auxiliary photoelectric detector 4, a measured photoelectric detector 5, an oscilloscope 6, and a control and data processing module 7.

[0031] The pulsed light source 1 is optically connected with the optical attenuator 2 for generating a light pulse excitation source for the measured photoelectric detector 5; the optical attenuator 2 is sequentially optically connected with the fiber optical power meter 3, the auxiliary photoelectric detector 4, and the measured photoelectric detector 5 for obtaining parameters of the light pulse excitation source and electrical signals generated by the measured photoelectric detector; the auxiliary photoelectric detector 4 and the measured photoelectric detector 5 are simultaneously electrically connected with the oscilloscope 6 for analyzing the electrical signals after photoelectric conversion; the control and data processing module 7 is sequentially data-connected with the pulsed light source 1, the fiber optical power meter 3, and the oscilloscope 6 for setting parameters of the pulsed light source 1, recording and processing the measured data.

[0032] In the present embodiment, the pulsed light source 1 can be a passively mode-locked laser or an ultra-continuum spectrum light source or a comb spectrum coherent light source, and the pulse width of the pulsed light source 1 is adjustable in the range of (10-200) ns.

[0033] A pulse response test method for a photoelectric detector, characterized by comprising the following steps:

[0034] S1: using the control and data processing module 7 to set the center frequency and pulse width of the pulsed light source 1;

[0035] S2: the pulsed light source 1 emits a light pulse signal, which is input into the optical attenuator 2 through a fiber active connector for a certain attenuation to avoid the saturation of the auxiliary photoelectric detector 4 or the measured photoelectric detector 5 due to the excessive optical power;

[0036] S3: the attenuated light pulse signal is first input into the fiber optical power meter 3 to obtain the average optical power of the light pulse excitation source, and the control and data processing module 7 records it as P a ;

[0037] S4: the light pulse excitation source is input into the auxiliary photodetector 4, and the electrical signal obtained after photoelectric conversion is input into the oscilloscope 6, the period and pulse width of the light pulse excitation source are obtained, and T and τ are recorded by the control and data processing module 7 respectively;

[0038] S5: the peak optical power P of the light pulse excitation source is calculated by the control and data processing module 7 p For

[0039]

[0040] S6: finally, the light pulse excitation source is input into the measured photodetector 5, and the electrical signal obtained after photoelectric conversion is collected by the oscilloscope 6, the peak voltage of the measured electrical signal is obtained, and V is recorded by the control and data processing module 7 m ;

[0041] S7: the pulse response degree R of the measured photodetector 5 is calculated by the control and data processing module 7 as

[0042]

[0043] Wherein, the unit of pulse response degree R is V / W;

[0044] S8: the pulse width of the pulse light source 1 is changed by the control and data processing module 7, and steps S2-S7 are repeated, so that the pulse response degree of the measured photodetector 5 under other pulse widths can be obtained.

[0045] Example one

[0046] In this embodiment, the control and data processing module is used to set the center frequency of the pulse light source to 1 kHz, the pulse width to 10 ns, and the center wavelength to 1064 nm. Then, the light pulse signal emitted by the pulse light source is input into the optical attenuator through the optical fiber active connector for attenuation, and the obtained light pulse excitation source is first input into the optical fiber optical power meter. The average optical power obtained by the control and data processing module is 39.85 nW (P a ). Then, the light pulse excitation source is input into the auxiliary photodetector for photoelectric conversion, the period and pulse width of the light pulse excitation source are obtained by the oscilloscope, and T and τ are recorded by the control and data processing module respectively. Then, the peak optical power of the light pulse excitation source can be calculated by the control and data processing module as 3.87 mW (P p ). Then, the light pulse excitation source is input into the measured photodetector, and the peak voltage of the measured electrical signal is obtained by the oscilloscope after photoelectric conversion, and V is recorded by the control and data processing module m). Finally, the pulse responsivity of the measured photodetector is calculated to be 11.93 V / W (R) by the control and data processing module.

[0047] Example Two

[0048] In this example, the control and data processing module is used to set the center frequency of the pulsed light source to be 1 kHz and the pulse width to be 150 ns, with the center wavelength being 1064 nm. The light pulse signal from the pulsed light source is then input into the optical attenuator through the fiber optic active connector for attenuation. The resulting optical pulse excitation source is first input into the fiber optic power meter, and the average optical power is recorded to be 634.97 nW (P a ) by the control and data processing module. Next, the optical pulse excitation source is input into the auxiliary photodetector for photoelectric conversion. The period and pulse width of the optical pulse excitation source are obtained by the oscilloscope and recorded to be 1.002 ms (T) and 150.60 ns (τ) by the control and data processing module, respectively. Then, the peak optical power of the optical pulse excitation source is calculated to be 4.22 mW (P p ) by the control and data processing module. Next, the optical pulse excitation source is input into the auxiliary photodetector for photoelectric conversion. The period and pulse width of the optical pulse excitation source are obtained by the oscilloscope and recorded to be 1.002 ms (T) and 150.60 ns (τ) by the control and data processing module, respectively. Then, the peak optical power of the optical pulse excitation source is calculated to be 4.22 mW (P m ) by the control and data processing module. Next, the optical pulse excitation source is input into the auxiliary photodetector for photoelectric conversion. The period and pulse width of the optical pulse excitation source are obtained by the oscilloscope and recorded to be 1.002 ms (T) and 150.60 ns (τ) by the control and data processing module, respectively. Then, the peak optical power of the optical pulse excitation source is calculated to be 4.22 mW (P

[0049] The present application is described in reference to the flowchart and / or block diagram of the method, apparatus (system) and computer program product according to an embodiment of the present application. It should be understood that each flow and / or block in the flowchart and / or block diagram, as well as a combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing apparatus to produce a machine, so that the instructions, which are executed via the processor of the computer or other programmable data processing apparatus, generate a means for implementing the functions specified in the flowchart and / or block diagram. Figure 1 The functions specified in a flow or multiple flows and / or blocks Figure 1 The means for implementing the functions specified in a flow or multiple flows and / or blocks.

[0050] These computer program instructions can also be stored in a computer-readable memory that can direct the computer or other programmable data processing apparatus to work in a specific manner, so that the instructions stored in the computer-readable memory produce a product including instruction means, which implement the functions specified in the flowchart and / or block diagram. Figure 1 The functions specified in a flow or multiple flows and / or blocks Figure 1 The means for implementing the functions specified in a flow or multiple flows and / or blocks.

[0051] These computer program instructions can also be loaded into a computer or other programmable data processing devices, so that a series of operational steps are performed on the computer or other programmable data processing devices to generate computer-implemented processes, thus the instructions executed on the computer or other programmable data processing devices provide the function of realizing the processes specified in the flowchart Figure 1 one flow or multiple flows and / or the functions specified in one block or multiple blocks. Figure 1 one flow or multiple flows and / or the functions specified in one block or multiple blocks.

[0052] The principles and implementation manners of the present application are described in the embodiments, and the above embodiment descriptions are only used to help understand the method of the present application and its core idea; meanwhile, for the ordinary skilled person in the art, according to the idea of the present application, the specific implementation manners and application scopes can be changed, and the above descriptions should not be understood as the limitation of the present application.

[0053] The person skilled in the art will understand that the embodiments described herein are used to help the reader understand the principles of the present application, and should be understood as the protection scope of the present application not being limited to such specific descriptions and embodiments. The person skilled in the art can make various other specific modifications and combinations according to the technical inspirations disclosed in the present application without departing from the essence of the present application, and these modifications and combinations are still within the protection scope of the present application.

Claims

1. A method for testing the impulse responsivity of a photodetector, characterized in that, Includes the following steps: S1: Use the control and data processing module (7) to set the center frequency and pulse width of the pulse light source (1); S2: The pulse light source (1) emits a light pulse signal, which is input to the optical attenuator (2) through the optical fiber active connector for a certain attenuation, so as to avoid the optical power being too large and causing the auxiliary photodetector (4) or the photodetector under test (5) to saturate. S3: The attenuated optical pulse signal is first input into the fiber optic power meter (3) to obtain the average optical power of the optical pulse excitation source, and then recorded by the control and data processing module (7). P a ; S4: The optical pulse excitation source is input into the auxiliary photodetector (4), and the electrical signal obtained after photoelectric conversion is input into the oscilloscope (6) to obtain the period and pulse width of the optical pulse excitation source, and the control and data processing module (7) records them respectively. T and τ ; S5: The peak optical power of the optical pulse excitation source is calculated using the control and data processing module (7). The specific calculation method is as follows: in, The peak optical power of the optical pulse excitation source is . The average optical power of the optical pulse excitation source, The period of the optical pulse excitation source is . The pulse width; S6: The optical pulse excitation source is input into the photodetector under test (5). The electrical signal obtained after photoelectric conversion is acquired by the oscilloscope (6), the peak voltage of the electrical signal under test is obtained, and the control and data processing module (7) records it as follows. V m ; S7: The impulse responsivity of the photodetector (5) under test is calculated using the control and data processing module (7). The specific calculation method is as follows: in, The average optical power of the optical pulse excitation source, The peak voltage of the measured electrical signal; S8: By using the control and data processing module (7) to change the pulse width of the pulse light source (1), and repeating steps S2 to S7, the pulse responsivity of the photodetector (5) under other pulse widths can be obtained.

2. The method according to claim 1, characterized in that, The pulsed light source is a passively mode-locked laser, a supercontinuum light source, or a comb-spectrum coherent light source, with a pulse width adjustable from 10 to 200 ns.

3. A testing apparatus for implementing the method of claim 1, characterized in that, include: It includes a pulsed light source (1), an optical attenuator (2), a fiber optic power meter (3), an auxiliary photodetector (4), a photodetector under test (5), an oscilloscope (6), and a control and data processing module (7). The pulse light source (1) is optically connected to the optical attenuator (2) to generate the optical pulse excitation source for the photodetector under test (5); the optical attenuator (2) is optically connected to the fiber optic power meter (3), the auxiliary photodetector (4), and the photodetector under test (5) in sequence to obtain the parameters of the optical pulse excitation source and the electrical signal generated by the photodetector under test; the auxiliary photodetector (4) and the photodetector under test (5) are simultaneously electrically connected to the oscilloscope (6) to analyze the electrical signal after photoelectric conversion; the control and data processing module (7) is data connected to the pulse light source (1), the fiber optic power meter (3), and the oscilloscope (6) in sequence to set the parameters of the pulse light source (1), record and process the measured data.

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