Responsivity measuring device and method for intermediate infrared detector

Abstract

The invention discloses a device and a method for measuring the response rate of an intermediate infrared detector, and solves the problem that the power density of an actual incident detector is not accurately measured when the response rate changes along with the temperature and / or the photosensitive surface of the detector is small in the calibration of the response rate of the intermediate infrared detector. The total laser power of the measurement laser can be measured by using the laser power meter, and the ratio of the power of the light spot emitted to the central area of the photosensitive surface of the detector to the total light spot power can be measured by using the light spot analyzer, so that the power density value emitted to the photosensitive surface of the detector can be accurately measured and calculated. And the measurement precision of the response rate of the intermediate infrared detector is improved.

Description

Technical Field

[0001] The invention relates to a mid-infrared detector, and in particular to a response rate measurement device and method for a mid-infrared detector. Background Art

[0002] With the rapid development of infrared laser detection technology, mid-infrared detectors are widely used in the field of mid-infrared photoelectric detection, especially in the measurement of laser parameters. Mid-infrared detectors realize the test of parameters such as the output power, spot distribution, and beam quality of the measured laser through photoelectric signal conversion. The response rate is an important performance parameter of the mid-infrared detector. It refers to the ratio of the signal generated by the detector to the incident light power of the wavelength at a specific wavelength, reflecting the sensitivity and detection accuracy of the device. However, the mid-infrared detector itself is sensitive to temperature, and the response rate will change with temperature, which directly affects the accuracy of the laser parameter measurement results.

[0003] At present, there are two internationally used testing methods for the response rate of mid-infrared detectors:

[0004] ① Using a black body as the radiation source, the power density incident on the detector is directly calculated using the black body radiation formula. The advantage of this method is that the black body is a stable radiation source, and the response rate test has a high accuracy rate. However, when the black body is a wide-spectrum radiation source, the response rate at a certain wavelength cannot be accurately measured.

[0005] ② Using laser as the radiation light source, the power density of the incident detector needs to be traced back to the cryogenic radiometer through a trap detector for measurement. This method is costly and complicated to operate.

[0006] In addition, both methods are limited by temperature drift. When the incident light radiates the mid-infrared detector, the detector temperature changes instantaneously, and the response rate changes with the temperature, so the accuracy cannot be improved.

[0007] The patent with publication number CN 102305663A, "A Calibration Device for the Change of Mid-Infrared Detector Response Rate with Temperature", controls the detector temperature through a high and low temperature control box and uses a black body + filter method to test the detector response rate. This method lacks real-time monitoring of the temperature of the detector's photosensitive surface and requires long-term temperature control to ensure that the temperature in the high and low temperature control box reaches thermal equilibrium, resulting in low measurement efficiency.

[0008] The patent "A method and system for testing room temperature response parameters of infrared detectors" with publication number CN 116295870A uses two light sources to irradiate simultaneously to calculate the response rate, linear dynamic range and saturation threshold of the detector under test. This method can only measure the response parameters of the detector at room temperature, and cannot measure the response parameters in a wide temperature range, which has certain limitations. Summary of the invention

[0009] In order to solve the technical problem of inaccurate measurement of the power density actually incident on the detector when the response rate varies with temperature and / or the detector photosensitivity surface is small during the response rate calibration of the mid-infrared detector, the present invention provides a response rate measurement device and method for the mid-infrared detector.

[0010] In order to achieve the above object, the present invention adopts the following technical solution:

[0011] A response rate measuring device for a mid-infrared detector, the mid-infrared detector comprising a Pt thin film resistor, a detector photosensitive surface, a detector electrode, a Pt resistor electrode and a common electrode; one end of the Pt thin film resistor is connected to the Pt resistor electrode, and the other end is connected to the common electrode; the common electrode and the detector electrode are both in contact with the detector photosensitive surface; the common electrode and the detector electrode constitute the output end of the mid-infrared detector;

[0012] Its special features are:

[0013] It includes a laser, a vacuum chamber, a current amplifier, an acquisition card, a laser power meter, a spot analyzer and a processing unit;

[0014] The laser is used to emit a measuring laser to the mid-infrared detector to be tested;

[0015] A light window corresponding to the measuring laser is provided on the side wall of the vacuum chamber, and a mid-infrared detector to be measured is arranged inside the vacuum chamber, and the photosensitive surface of the detector is made to correspond to the light window;

[0016] The input end of the current amplifier is used to be connected to the output end of the mid-infrared detector to be tested, so as to convert the current signal output by the mid-infrared detector to be tested into a voltage signal and amplify it;

[0017] The input end of the acquisition card is connected to the output end of the current amplifier, and is used to acquire the voltage signal output by the current amplifier;

[0018] The laser power meter is used to measure the laser power of the measuring laser;

[0019] The light spot analyzer is used to measure the light spot shape of the measuring laser;

[0020] The processing unit is connected to the output end of the acquisition card and is used to calculate the response rate of the mid-infrared detector to be tested according to the current signal, laser power and light spot shape.

[0021] Further, it also includes a temperature control unit;

[0022] The active end of the temperature control unit is connected to the vacuum chamber and is used to control the temperature in the vacuum chamber.

[0023] Further, the temperature control unit includes a temperature controller, a heating / cooling machine and a temperature measuring instrument;

[0024] The control end of the temperature controller is connected to the input end of the heating / refrigerating machine, and is used to control the heating / refrigerating machine to heat or cool;

[0025] The heating / cooling end of the heating / cooling machine is connected to the vacuum chamber and is used to heat or cool the vacuum chamber;

[0026] The temperature measuring instrument is arranged in the vacuum chamber, and its output end is connected to the input end of the temperature controller, so as to provide the temperature controller with real-time feedback of the temperature in the vacuum chamber.

[0027] Further, it also includes a resistance measuring unit;

[0028] The measuring end of the resistance measuring unit is connected to the Pt resistance electrode and the common electrode, and the output end is connected to the processing unit for real-time monitoring of the resistance value of the Pt thin film resistor and sending the result to the processing unit.

[0029] Furthermore, it also includes a damping sheet;

[0030] The attenuation sheet is arranged on the optical path of the measuring laser between the laser and the vacuum cavity, and is used to attenuate the energy of the measuring laser to prevent the measuring laser from damaging the mid-infrared detector to be measured.

[0031] Furthermore, the body of the vacuum chamber is made of stainless steel, and the light window on the side wall is made of white sapphire.

[0032] Furthermore, the laser adopts a 3.8 μm quantum cascade laser, and the output is a Gaussian spot with a spot diameter of 2.5 to 3.5 mm.

[0033] Furthermore, the attenuation film adopts a mid-infrared neutral density attenuation film with a transmittance of 10%;

[0034] The acquisition card is a NI data acquisition card;

[0035] The laser power meter is an Ophir laser power meter with a sensitive pyroelectric probe and a measuring range of 3W;

[0036] The light spot analyzer adopts DataRay light spot analyzer, which can measure the wavelength range of 2μm to 16μm;

[0037] The current amplifier adopts Stanford SR570 current amplifier;

[0038] The resistance measuring unit adopts a multimeter.

[0039] Furthermore, the temperature measuring instrument adopts a thermistor.

[0040] A method for measuring the response rate of a mid-infrared detector, using the above-mentioned device for measuring the response rate of a mid-infrared detector, is characterized in that it comprises the following steps:

[0041] Step 1, place the mid-infrared detector to be tested into a vacuum chamber, and make the photosensitive surface of the detector correspond to the light window on the vacuum chamber, lead the output end signal line of the mid-infrared detector to be tested out of the vacuum chamber, and connect the current amplifier, acquisition card and processing unit in sequence, and set the temperature of the vacuum chamber to a preset temperature through the temperature control unit;

[0042] Step 2, turn on the laser, the laser emits a measuring laser, and the measuring laser passes through the optical window on the vacuum chamber to reach the detector photosensitive surface of the mid-infrared detector to be tested; the mid-infrared detector to be tested converts the received measuring laser into a current signal and sends it to the current amplifier, and the current amplifier converts the received current signal into a voltage signal U;

[0043] Step 3: Collect the voltage signal U through the acquisition card and send it to the processing unit;

[0044] Step 4, measuring the spot shape of the measuring laser emitted by the laser by using a spot analyzer;

[0045] Step 5: The processing unit obtains the light spot shape and calculates the ratio k of the light spot power in the central area to the total light spot power; the size of the central area is consistent with the size of the detector photosensitive surface of the mid-infrared detector to be tested;

[0046] Step 6: Use a laser power meter to measure the total laser power P of the measurement laser emitted by the laser, and send it to the processing unit;

[0047] Step 7: The processing unit calculates the response rate R' incident on the mid-infrared detector to be tested:

[0048]

[0049] Where G is the amplification factor of the current amplifier, and T is the transmittance of the optical window on the vacuum cavity to the measurement laser;

[0050] Step 8: gradually increase the power of the measuring laser emitted by the laser until the voltage signal U collected by the acquisition card does not increase linearly with the measuring laser power; each time the power increases, repeat steps 3 to 7 to obtain multiple response rates R', and obtain the average of the multiple response rates R', which is the response rate R of the mid-infrared detector to be tested.

[0051] Beneficial effects of the present invention:

[0052] 1. The present invention provides a response rate measurement device and method for a mid-infrared detector, which solves the problem of inaccurate measurement of the actual laser power density received by the mid-infrared detector when the detector photosensitive surface of the mid-infrared detector is smaller than the spot size of the measuring laser. The total laser power of the measuring laser can be measured by a laser power meter, and the ratio of the spot power in the central area incident on the detector photosensitive surface to the total spot power can be measured by a spot analyzer, thereby accurately measuring and calculating the power density value incident on the detector photosensitive surface, thereby improving the measurement accuracy of the response rate of the mid-infrared detector.

[0053] 2. The present invention sets the mid-infrared detector in a vacuum chamber and provides a temperature control unit for the vacuum chamber. The temperature control unit can ensure that the temperature of the vacuum chamber is in a stable state, thereby eliminating the influence of temperature on the response rate of the mid-infrared detector and improving the measurement accuracy of the response rate of the mid-infrared detector. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 is a schematic diagram of the structure of the mid-infrared detector to be tested;

[0055] Figure Number:

[0056] 11-Pt thin film resistor, 12-detector photosensitive surface, 13-detector electrode, 14-Pt resistor electrode, 15-common electrode;

[0057] Figure 2 It is a structural schematic diagram of an embodiment of a response rate measuring device for a mid-infrared detector of the present invention (excluding a laser power meter and a spot analyzer);

[0058] Figure 3 is a structural schematic diagram of measuring the spot shape by a spot analyzer in step 4 of an embodiment of the present invention;

[0059] Figure 4 is a schematic diagram of the structure of using a laser power meter to measure the total laser power in step 6 of an embodiment of the present invention;

[0060] Figure 5 is a curve diagram showing the relationship between the response rate R' and the voltage signal U measured in an embodiment of the present invention;

[0061] Figure Number:

[0062] 1-laser, 2-attenuation plate, 3-vacuum chamber, 4-mid-infrared detector to be tested, 5-heating / refrigerating machine, 6-temperature controller, 7-current amplifier, 8-acquisition card, 9-processing unit, 10-multimeter, 16-laser power meter, 17-spot analyzer. DETAILED DESCRIPTION

[0063] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than 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.

[0064] First, if Figure 1 As shown, the mid-infrared detector includes a Pt thin film resistor 11, a detector photosensitive surface 12, a detector electrode 13, a Pt resistor electrode 14 and a common electrode 15; one end of the Pt thin film resistor 11 is connected to the Pt resistor electrode 14, and the other end is connected to the common electrode 15. The Pt thin film resistor 11 adopts a thin film platinum filament structure with a line width of 15μm; the common electrode 15 and the detector electrode 13 are both in contact with the detector photosensitive surface 12; the common electrode 15 and the detector electrode 13 constitute the output end of the mid-infrared detector. In this embodiment, the mid-infrared detector 4 to be tested adopts a photovoltaic type mercury cadmium telluride detector with a size of 0.1×0.1mm for the detector photosensitive surface 12, and the converted current signal is led out through the detector electrode 13 and the common electrode 14. The Pt thin film resistor 11 is etched on the detector at the same time, and the detector temperature is monitored in real time, and the resistance value signal is led out through the Pt resistor electrode 14 and the common electrode 15.

[0065] An embodiment of the present invention provides a responsivity measurement device for a mid-infrared detector, such as Figure 2 As shown, it includes a laser 1, an attenuation plate 2, a vacuum chamber 3, a temperature control unit, a current amplifier 7, an acquisition card 8, a multimeter 10, a laser power meter 16, a spot analyzer 17 and a processing unit 9;

[0066] The laser 1 is used to emit a measuring laser to the mid-infrared detector 4 to be measured; the laser 1 adopts a 3.8 μm quantum cascade laser, and the output is a Gaussian spot with a spot diameter of about 3 mm.

[0067] The side wall of the vacuum chamber 3 is provided with an optical window corresponding to the measuring laser. The interior of the vacuum chamber 3 is used to set the mid-infrared detector 4 to be measured, and the detector photosensitive surface 12 is made to correspond to the optical window. The cavity of the vacuum chamber 3 is made of stainless steel material, with an inner diameter of 200 mm, and the vacuum degree can be maintained at 10 -4 Pa; the light window on the side wall of the vacuum chamber 3 is made of white sapphire material with high transmittance in the mid-infrared band.

[0068] The attenuation sheet 2 is arranged on the optical path of the measuring laser between the laser 1 and the vacuum chamber 3, and is used to attenuate the energy of the measuring laser to prevent the measuring laser from damaging the mid-infrared detector 4 to be measured. In this embodiment, the attenuation sheet 2 is a mid-infrared neutral density attenuation sheet with a transmittance of 10%;

[0069] The active end of the temperature control unit is connected to the vacuum chamber 3 and is used to control the temperature in the vacuum chamber 3;

[0070] The input end of the current amplifier 7 is used to connect with the output end of the mid-infrared detector 4 to be tested, so as to convert the current signal output by the mid-infrared detector 4 to a voltage signal and amplify it; the current amplifier 7 adopts the Stanford SR570 current amplifier, and the amplification gear is 100μA|V (that is, every 100μA current is converted into 1V voltage, G=10 4 ), the amplified voltage is collected by the NI data acquisition card and then displayed by the computer.

[0071] The input end of the acquisition card 8 is connected to the output end of the current amplifier 7, and is used to acquire the voltage signal output by the current amplifier 7; the acquisition card 8 is a NI data acquisition card;

[0072] The laser power meter 16 is used to measure the laser power of the measuring laser; the laser power meter 16 is an Ophir laser power meter with a sensitive pyroelectric probe and a measuring range of 3W.

[0073] The spot analyzer 17 is used to measure the spot shape of the measuring laser; the spot analyzer 17 adopts DataRay spot analyzer, and the measurable wavelength range is 2μm to 16μm;

[0074] The measuring end of the multimeter 10 is connected to the Pt resistor electrode 14 and the common electrode 15 , and the output end of the multimeter 10 is connected to the processing unit 9 for real-time monitoring of the resistance value of the Pt thin film resistor 11 and sending the resistance value to the processing unit 9 .

[0075] The temperature control unit includes a temperature controller 6, a heating / refrigerating machine 7 and a thermometer 18; the control end of the temperature controller 6 is connected to the input end of the heating / refrigerating machine 7, and is used to control the heating or cooling of the heating / refrigerating machine 7; the heating / refrigerating end of the heating / refrigerating machine 7 is connected to the vacuum chamber 3, and is used to heat or cool the vacuum chamber 3; the thermometer 18 is arranged in the vacuum chamber 3, and its output end is connected to the input end of the temperature controller 6, and is used to feed back the temperature in the vacuum chamber 3 to the temperature controller 6 in real time. In this embodiment, the thermometer 18 adopts a thermistor.

[0076] The processing unit 9 is connected to the output end of the acquisition card 8 and the output end of the multimeter 10, and is used to calculate the response rate of the mid-infrared detector 4 to be tested according to the current signal, laser power and spot shape. In this embodiment, the processing unit 9 is a computer.

[0077] The measuring laser emitted by the laser 1 is attenuated by the attenuation plate 2, and is incident on the mid-infrared detector 4 to be tested through the white sapphire light window of the vacuum chamber 3. The mid-infrared detector 4 to be tested converts the optical signal into a current signal and inputs it into the current amplifier 7. The current amplifier 7 converts the current signal into a voltage signal. The output voltage signal is collected by the NI data acquisition card. The real-time resistance of the Pt thin film resistor 11 is measured by the multimeter 10, and the response voltage value and the Pt resistance value are displayed by the computer. The laser power density of the laser 1 incident on the detector photosensitive surface 12 is measured by the laser power meter 16 and the spot analyzer 17.

[0078] The above measuring device is used to measure the response rate of the mid-infrared detector 4 to be measured:

[0079] Step 1, place the mid-infrared detector 4 to be tested into the vacuum chamber 3, and make the detector photosensitive surface 12 correspond to the light window on the vacuum chamber 3, lead the output end signal line of the mid-infrared detector 4 to be tested out of the vacuum chamber 3, and connect the current amplifier 7, the acquisition card 8 and the processing unit in sequence, close the vacuum chamber 3 and evacuate the vacuum chamber, and set the temperature of the vacuum chamber 3 to 10°C through the temperature control unit; use a multimeter 10 to measure the resistance value of the Pt thin film resistor 11. When the resistance remains unchanged at 207.58Ω, it indicates that the mid-infrared detector to be tested has reached a thermal equilibrium state and the temperature is stable at 10°C.

[0080] Step 2, turn on the laser 1, the laser 1 emits a measuring laser, the measuring laser passes through the light window on the vacuum chamber 3 to reach the detector photosensitive surface 12 of the mid-infrared detector 4 to be tested; the mid-infrared detector 4 to be tested converts the received measuring laser into a current signal and sends it to the current amplifier 7, and the current amplifier 7 converts the received current signal into a voltage signal U=53.5mW.

[0081] Step 3: Collect the voltage signal U through the acquisition card 8 and send it to the processing unit.

[0082] Step 4: Figure 2 As shown, the spot shape of the measuring laser light emitted by the laser 1 is measured by the spot analyzer 17 .

[0083] Step 5, the processing unit obtains the spot shape, and calculates the ratio k=0.0121 of the spot power of the central area S=0.1mm×0.1mm to the total spot power; the size of the central area is consistent with the size of the detector photosensitive surface 12 of the mid-infrared detector 4 to be tested.

[0084] Step 6: Figure 4 As shown, a laser power meter 16 is used to measure the total laser power P = 6.24 mW emitted by the laser 1 after the measured laser passes through the attenuation plate 2 with a transmittance of 10%, and sends it to the processing unit.

[0085] At this time, the power incident on the detector photosensitive surface 12 is calculated by the following formula:

[0086] P′=0.9kP=0.068mW

[0087] Among them, 0.9 is the transmittance of the white sapphire material window at a wavelength of 3.8μm;

[0088] Step 7: The processing unit calculates the response rate R′ incident on the mid-infrared detector 4 to be tested:

[0089]

[0090] Wherein, G is the gain of the current amplifier 7, and T=0.9.

[0091] Step 8: gradually increase the power of the measuring laser emitted by the laser 1 until the voltage signal U collected by the acquisition card 8 does not increase linearly with the measuring laser power; each time the power increases, repeat steps 3 to 7. Figure 5 As shown, the response voltages corresponding to different powers of 0.068 mW, 0.070 mW, 0.073 mW… are 535.0 mV, 554.7 mV, 574.3 mV… and the corresponding response rates are 0.79 A / W, 0.79 A / W, 0.79 A / W…, and the average of the response rates 0.79 A / W, 0.79 A / W, 0.79 A / W… is obtained, which is the response rate R = 0.79 A / W of the mercury cadmium telluride mid-infrared detector.

[0092] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A response rate measuring device for a mid-infrared detector, the mid-infrared detector comprising a Pt thin film resistor (11), a detector photosensitive surface (12), a detector electrode (13), a Pt resistor electrode (14) and a common electrode (15); one end of the Pt thin film resistor (11) is connected to the Pt resistor electrode (14), and the other end is connected to the common electrode (15); the common electrode (15) and the detector electrode (13) are both in contact with the detector photosensitive surface (12); the common electrode (15) and the detector electrode (13) constitute the output end of the mid-infrared detector; Features: It comprises a laser (1), a vacuum chamber (3), a current amplifier (7), an acquisition card (8), a laser power meter (16), a light spot analyzer (17) and a processing unit (9); The laser (1) is used to emit a measuring laser to a mid-infrared detector (4) to be measured; A light window corresponding to the measuring laser is provided on the side wall of the vacuum chamber (3); a mid-infrared detector (4) to be measured is arranged inside the vacuum chamber (3), and the detector photosensitive surface (12) is made to correspond to the light window; The input end of the current amplifier (7) is used to be connected to the output end of the mid-infrared detector (4) to be tested, so as to convert the current signal output by the mid-infrared detector (4) to be tested into a voltage signal and amplify the voltage signal; The input end of the acquisition card (8) is connected to the output end of the current amplifier (7) and is used to acquire the voltage signal output by the current amplifier (7); The laser power meter (16) is used to measure the laser power of the measuring laser; The light spot analyzer (17) is used to measure the light spot shape of the measuring laser; The processing unit (9) is connected to the output end of the acquisition card (8) and is used to calculate the response rate of the mid-infrared detector (4) to be tested according to the current signal, laser power and light spot shape.

2. The responsivity measuring device for a mid-infrared detector according to claim 1, characterized in that: It also includes a temperature control unit; The active end of the temperature control unit is connected to the vacuum chamber (3) and is used to control the temperature in the vacuum chamber (3).

3. The responsivity measuring device for a mid-infrared detector according to claim 2, characterized in that: The temperature control unit comprises a temperature controller (6), a heating / refrigerating machine (7) and a temperature measuring instrument (18); The control end of the temperature controller (6) is connected to the input end of the heating / refrigerating machine (7) and is used to control the heating / refrigerating machine (7) to heat or cool; The heating / cooling end of the heating / cooling machine (7) is connected to the vacuum chamber (3) and is used to heat or cool the vacuum chamber (3); The temperature measuring instrument (18) is arranged in the vacuum chamber (3), and its output end is connected to the input end of the temperature controller (6) for providing real-time feedback of the temperature in the vacuum chamber (3) to the temperature controller (6).

4. The responsivity measuring device for a mid-infrared detector according to claim 1, 2 or 3, characterized in that: Also included is a resistance measuring unit; The measuring end of the resistance measuring unit is connected to the Pt resistance electrode (14) and the common electrode (15), and the output end is connected to the processing unit (9) for real-time monitoring of the resistance value of the Pt thin film resistor (11) and sending the resistance value to the processing unit (9).

5. The responsivity measuring device for a mid-infrared detector according to claim 4, characterized in that: Also includes a damping sheet (2); The attenuation plate (2) is arranged on the optical path of the measuring laser between the laser (1) and the vacuum chamber (3) and is used to attenuate the energy of the measuring laser to prevent the measuring laser from damaging the mid-infrared detector (4) to be measured.

6. The responsivity measuring device for a mid-infrared detector according to claim 5, characterized in that: The body of the vacuum chamber (3) is made of stainless steel, and the light window on the side wall is made of white sapphire.

7. The responsivity measuring device for a mid-infrared detector according to claim 6, characterized in that: The laser (1) adopts a 3.8 μm quantum cascade laser, and the output is a Gaussian spot with a spot diameter of 2.5 to 3.5 mm.

8. The responsivity measuring device for a mid-infrared detector according to claim 7, characterized in that: The attenuation film (2) is a mid-infrared neutral density attenuation film with a transmittance of 10%; The acquisition card (8) is a NI data acquisition card; The laser power meter (16) is an Ophir laser power meter with a sensitive pyroelectric probe and a measuring range of 3W; The light spot analyzer (17) adopts a DataRay light spot analyzer, and the measurable wavelength range is 2 μm to 16 μm; The current amplifier (7) adopts Stanford SR570 current amplifier; The resistance measuring unit adopts a multimeter (10).

9. The responsivity measuring device for a mid-infrared detector according to claim 3, characterized in that: The temperature measuring instrument (18) adopts a thermistor.

10. A method for measuring the response rate of a mid-infrared detector, using the device for measuring the response rate of a mid-infrared detector according to any one of claims 1 to 9, characterized in that: The following steps are involved: Step 1, placing a mid-infrared detector (4) to be tested into a vacuum chamber (3), and making the detector photosensitive surface (12) correspond to the light window on the vacuum chamber (3), leading the output end signal line of the mid-infrared detector (4) to be tested out of the vacuum chamber (3), and connecting the current amplifier (7), the acquisition card (8) and the processing unit in sequence, and setting the temperature of the vacuum chamber (3) to a preset temperature through the temperature control unit; Step 2, turning on the laser (1), the laser (1) emits a measuring laser, and the measuring laser passes through the optical window on the vacuum chamber (3) to reach the detector photosensitive surface (12) of the mid-infrared detector (4) to be tested; the mid-infrared detector (4) to be tested converts the received measuring laser into a current signal and sends it to the current amplifier (7), and the current amplifier (7) converts the received current signal into a voltage signal U; Step 3: collecting the voltage signal U through the acquisition card (8) and sending it to the processing unit; Step 4, measuring the spot shape of the measuring laser emitted by the laser (1) by means of a spot analyzer (17); Step 5: The processing unit obtains the light spot shape and calculates the ratio k of the light spot power in the central area to the total light spot power; the size of the central area is consistent with the size of the detector photosensitive surface (12) of the mid-infrared detector (4) to be tested; Step 6: Using a laser power meter (16) to measure the total laser power P of the measuring laser emitted by the laser (1), and sending the result to a processing unit; Step 7: The processing unit calculates the response rate R' of the incident light to the mid-infrared detector (4) to be tested: Wherein, G is the amplification factor of the current amplifier (7), and T is the transmittance of the optical window on the vacuum chamber (3) to the measuring laser; Step 8, gradually increase the power of the measuring laser emitted by the laser (1) until the voltage signal U collected by the acquisition card (8) does not increase linearly with the measuring laser power; each time the power increases, repeat steps 3 to 7, thereby obtaining a plurality of response rates R', and obtaining an average value of the plurality of response rates R', which is the response rate R of the mid-infrared detector (4) to be measured.

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