Device and method for detecting performance of laser range finder

Abstract

The invention discloses a device and a method for detecting the performance of a laser range finder, relates to the technical field of optical detection, and aims to solve the problems that the detection process of the minimum detectable power of the laser range finder is not convenient enough and the detection result is not visual enough due to insufficient utilization of a laser source in the prior art. The device is composed of a 99: 1 beam splitter, a total reflection mirror I, a fixed optical attenuator I, an adjustable optical attenuator, an optical fiber coupler, a diverging lens, an optical energy meter probe, a single-mode optical fiber, an optical fiber collimator, a 50: 50 beam splitter, a converging lens, a photoelectric detector, a fixed optical attenuator II, a total reflection mirror II, a pentagonal prism, an optical energy meter head, an oscilloscope, a temperature and humidity sensor and a heating wire. According to the invention, the full utilization of a single laser source is realized, the measurement process of the receiving sensitivity of the laser range finder is simplified, the detection result is more convenient and visual, and the laser range finder has the capability of simultaneously measuring the receiving sensitivity and laser energy of the laser range finder.

Description

Technical Field

[0001] This invention relates to the field of optical testing technology, specifically to a laser rangefinder performance testing device and method. Background Technology

[0002] Laser rangefinders, as a type of laser measuring instrument, play a crucial role in military, surveying, construction engineering, and autonomous driving. The laser intensity and detector sensitivity of a laser rangefinder are important indicators for verifying its performance and are an indispensable part of its acceptance testing. Similarly, testing the detector's sensitivity under different environments is also essential for device acceptance testing. Current technologies for measuring laser intensity and sensitivity focus on single measurements, which are either complex with complicated testing equipment and cumbersome processes, or limited by weather and location, causing numerous inconveniences in actual measurements. For measuring receiver sensitivity, existing technologies mainly include optical power meter detection and pulse... Methods such as time-of-flight detection and phase detection, as well as optical power meter detection, require adjustment of the optical path each time a laser rangefinder receiver can accurately receive the signal. Furthermore, the optical power meter measures average power, which is insufficient for dynamic measurements. It also requires multiple measurements of the receiver's optical power using the optical power meter probe, resulting in frequent operations and extremely low efficiency. Additionally, the receiver sensitivity is affected by atmospheric conditions such as temperature and humidity, which influence laser propagation and alter the intensity and characteristics of the reflected light signal, increasing the difficulty of accurate signal reception by the detector. This makes environmental simulation a crucial part of laser rangefinder acceptance testing. Outdoor environments present many uncontrollable factors, and current technologies are neither comprehensive nor precise enough for indoor environmental simulation.

[0003] The Chinese patent authorization announcement number is "CN102243301B", and the patent name is "Laser Rangefinder Detection Device". This device consists of a sampler, an absorber, a multi-target simulator, a standard target plate, and a variable aperture. The laser rangefinder emits a laser at the detection device, and the sampler and the multi-target simulator simulate the laser target echo. The laser rangefinder's receiving optical axis and minimum detectable power are obtained through the maximum distance measurement result. However, the underutilization of the laser source makes the detection process of minimum detectable power inconvenient and the detection results not intuitive. Summary of the Invention

[0004] In order to solve the problems of inefficient use of laser sources in existing technologies, which leads to inconvenient detection process and unintuitive detection results for minimum detectable power, this invention proposes a laser rangefinder performance testing device and method.

[0005] A laser rangefinder performance testing device includes: a 99:1 beam splitter, a total reflection mirror, a fixed optical attenuator, an adjustable optical attenuator, an optical fiber coupler, a diverging lens, a light energy meter probe, a single-mode optical fiber, an optical fiber collimator, a 50:50 beam splitter, a converging lens, a photodetector, a fixed optical attenuator, a total reflection mirror, a pentagonal prism, a light energy meter head, an oscilloscope, a temperature and humidity sensor, a heating wire, a cooling element, and a housing.

[0006] The 99:1 beam splitter is placed at a 45° angle to the laser incident direction. The 99:1 beam splitter, diverging lens, and optical energy meter probe are coaxially positioned. The total reflection mirror is also placed at a 45° angle to the laser incident direction. The total reflection mirror, fixed optical attenuator, adjustable optical attenuator, and fiber coupler are coaxially positioned. The fiber coupler is connected to a single-mode fiber, which in turn is connected to a fiber collimator. The fiber coupler and the fiber collimator are placed parallel to their optical axes. The 50:50 beam splitter is positioned at the laser incident direction. The optical fiber collimator, 50:50 beam splitter, fixed optical attenuator II, and total reflection mirror II are placed at a 45° angle to the laser incident direction. The 50:50 beam splitter, converging lens, and photodetector are placed coaxially. The photodetector is connected to the oscilloscope, and the optical energy meter probe is connected to the optical energy meter head. The optical energy meter head and oscilloscope are fixed to the outer wall of the housing. The temperature and humidity sensor, heating wire, and cooling chip are all fixed to the inner wall of the housing.

[0007] A laser emitted from the laser rangefinder's emission window is incident on a 99:1 beam splitter. The 99:1 beam splitter divides the laser energy into two parts. The 1% portion of the light passes through a diverging lens and is received by a photoelectric energy meter probe to measure the laser energy. The 99% portion of the light is reflected by a total reflection mirror. The reflected light then passes through a fixed optical attenuator and an adjustable optical attenuator for energy attenuation. The attenuated light is coupled into a single-mode fiber via a fiber coupler. The outgoing light from the single-mode fiber enters a fiber collimator for collimation. The collimated light is then split into two parts by a 50:50 beam splitter. One part of the light... The light is focused onto the photodetector by a converging lens to measure the receiving sensitivity. Another portion of the light is attenuated by a fixed optical attenuator and then reflected by a total reflection mirror. The reflected light passes through a pentagonal prism and is then incident on the receiving window of the laser rangefinder for distance measurement. The energy detected by the optical energy meter probe is displayed on the optical energy meter meter. The data detected by the photodetector is displayed on an oscilloscope for data analysis. The temperature and humidity sensor is used to detect and acquire the internal temperature and humidity information of the device. The heating wire is used to raise the internal temperature of the device, and the cooling chip is used to lower the internal temperature of the device.

[0008] A method for testing the performance of a laser rangefinder, the method comprising the following steps:

[0009] Step 1: Adjust the position of each optical component to align the optical path;

[0010] Place the laser rangefinder inside the device, adjust the relative position of the laser rangefinder and the optical system, start the laser rangefinder to emit laser light, and make the laser light incident at 45° onto the 99:1 beam splitter. Then adjust the position of the pentagonal prism so that the light emitted from it is aligned with the receiving window of the laser rangefinder.

[0011] Step 2: Detection of laser energy parameters;

[0012] Based on the specifications of the laser rangefinder, adjust the parameters of the optical energy meter and oscilloscope, observe the parameters of the optical energy meter, and fine-tune the position of the laser rangefinder according to the displayed parameters to maximize the displayed parameters. After reaching the maximum value, fix the position of the laser rangefinder. The laser energy parameters are:

[0013]

[0014] η tx η represents the transmittance of the laser rangefinder transmitter. split The beam splitting ratio is 99:1 for the beam splitter, and E1 is the parameter displayed on the light energy meter.

[0015] Step 3: Testing the receiver sensitivity of the laser rangefinder;

[0016] Seal the device and use a heating wire and a cooling plate to adjust the internal temperature to the required simulated ambient temperature. Set the adjustable optical attenuator to its maximum attenuation value, turn on the laser rangefinder to emit laser light, and slowly adjust the adjustable optical attenuator while observing the laser rangefinder until it reaches the critical value that allows it to measure distance. Record the critical voltage value V2 using an oscilloscope. Combined with the photodetector responsivity R, calculate the received power of the photodetector.

[0017]

[0018] The receiver sensitivity of the laser rangefinder is:

[0019]

[0020] Where η rx η represents the transmittance of the laser rangefinder receiver. fixed2 To fix the attenuation rate of optical attenuator two.

[0021] The beneficial effects of this invention are:

[0022] (1) The device and housing integrate optical and temperature and humidity control modules, which realizes the miniaturization and convenience of the device, solves the impact of weather factors on equipment acceptance test, provides a stable test environment for the range measurement capability test of laser range measuring equipment, and makes indoor environment simulation simpler.

[0023] (2) The 99:1 beam splitter is used to split the laser energy into two paths. One part is used to measure the emitted energy in real time, and the other part is used to simulate long-distance transmission through fiber delay. The 50:50 beam splitter splits the laser energy into two paths. One part is used to measure the receiving sensitivity in real time, and the other part is used to trigger the laser rangefinder receiver for distance measurement. This realizes the multi-functional use of a single light source, simplifies the optical path design, makes full use of the laser rangefinder's own light source, and simplifies the measurement process of receiving sensitivity, making the detection more convenient.

[0024] (3) The combination of photodetector and oscilloscope is used to replace the traditional optical power meter. The dynamic waveform of high frequency pulse signal can be captured in real time, which significantly improves the dynamic range measurement accuracy of receiving sensitivity. Combined with adjustable optical attenuator and converging lens, the critical receiving power under different attenuation conditions can be accurately simulated. It is suitable for the performance evaluation of high frequency pulse laser rangefinder. The pentagonal prism used solves the problem of inflexible alignment between the laser rangefinder's receiving light source and receiving window, and improves the alignment efficiency and accuracy.

[0025] (4) By simulating different temperature and humidity environments through heating wires and cooling plates, combined with the air chamber sealing design, the shortcomings of existing technologies that cannot truly reflect the influence of weather factors on laser propagation are solved. At the same time, the environmental conditions are stable and controllable during the test, avoiding the uncontrollability of outdoor testing. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of a laser rangefinder performance testing device based on the present invention. Detailed Implementation

[0027] The following describes in detail, with reference to the accompanying drawings, examples of implementation of the method of the present invention.

[0028] like Figure 1 As shown, a laser rangefinder performance testing device includes: a 99:1 beam splitter 1, a total reflection mirror 2, a fixed optical attenuator 3, an adjustable optical attenuator 4, an optical fiber coupler 5, a diverging lens 6, a light energy meter probe 7, a single-mode optical fiber 8, an optical fiber collimator 9, a 50:50 beam splitter 10, a converging lens 11, a photodetector 12, a fixed optical attenuator 2 13, a total reflection mirror 2 14, a pentagonal prism 15, a light energy meter head 16, an oscilloscope 17, a temperature and humidity sensor 18, a heating wire 19, a cooling element 20, and a housing 21.

[0029] The 99:1 beam splitter 1, total reflection mirror 2, fixed optical attenuator 3, adjustable optical attenuator 4, fiber optic coupler 5, diverging lens 6, optical energy meter probe 7, single-mode fiber 8, fiber optic collimator 9, 50:50 beam splitter 10, converging lens 11, photodetector 12, fixed optical attenuator 2 13, total reflection mirror 2 14, and pentagonal prism 15 are disposed inside the housing 21.

[0030] The 99:1 beam splitter 1 is placed at a 45° angle to the laser incident direction. The 99:1 beam splitter 1, the diverging lens 6, and the optical energy meter probe 7 are placed coaxially. The total reflection mirror 2 is placed at a 45° angle to the laser incident direction. The total reflection mirror 2, the fixed optical attenuator 3, the adjustable optical attenuator 4, and the fiber coupler 5 are placed coaxially. The fiber coupler 5 is connected to the single-mode fiber 8, and the single-mode fiber 8 is connected to the fiber collimator 9. The optical axes of the fiber coupler 5 and the fiber collimator 9 are parallel. The 50:50 beam splitter 10 is placed at a 45° angle to the laser incident direction. The fiber collimator 9, the 50:50 beam splitter 10, the fixed optical attenuator 13, and the total reflection mirror 14 are placed coaxially. The total reflection mirror 14 is placed at a 45° angle to the laser incident direction. The 50:50 beam splitter 10, the converging lens 11, and the photodetector 12 are placed coaxially. The photodetector 12 is connected to the oscilloscope 17. The optical energy meter probe 7 is connected to the optical energy meter head 16. The optical energy meter head 16 and the oscilloscope 17 are fixed on the outer wall of the housing. The temperature and humidity sensor 18, the heating wire 19, and the cooling chip 20 are all fixed on the inner wall of the housing 21.

[0031] A laser emitted from the laser rangefinder's emission window is incident on a 99:1 beam splitter 1. The 99:1 beam splitter 1 splits the laser energy into two parts. The 1% portion of the light passes through a diverging lens 6 and is received by a light energy meter probe 7 to measure the laser energy. The 99% portion of the light is reflected by a total reflection mirror 2. The reflected light then passes through a fixed optical attenuator 3 and an adjustable optical attenuator 4 to attenuate the laser energy. The attenuated light is coupled into a single-mode fiber 8 through a fiber coupler 5. The outgoing light from the single-mode fiber enters a fiber collimator 9 for collimation. The collimated light is then split into two parts by a 50:50 beam splitter 10. One part of the light passes through a converging lens... The light 11 is focused onto the photodetector 12 to measure the receiving sensitivity. Another part of the light is attenuated by the fixed optical attenuator 13 and then reflected by the total reflection mirror 14. The reflected light passes through the pentaprism 15 and is then incident on the receiving window of the laser rangefinder for distance measurement. The energy detected by the optical energy meter probe 7 is displayed by the optical energy meter meter 16. The data detected by the photodetector 12 is displayed by the oscilloscope 17 for data analysis. The temperature and humidity sensor 18 is used to detect and acquire the temperature and humidity information inside the device. The heating wire 19 is used to raise the temperature inside the device, and the cooling chip 20 is used to lower the temperature inside the device.

[0032] The 99:1 beam splitter 1 uses ordinary uncoated BK7 glass.

[0033] The fixed optical attenuator 3 is composed of multiple sets of neutral density filters to reduce laser pulse energy and prevent damage to downstream components.

[0034] The adjustable optical attenuator 4 employs two polarizers. Beam energy attenuation is achieved by adjusting the polarization angle of the rear polarizer relative to the front polarizer, satisfying Malus's law I=I0cos 2 θ, where I0 is the initial light intensity, θ is the angle between the two polarizers, and I is the light intensity after passing through the attenuator. The angles are marked on the two polarizers of the adjustable light attenuator 4.

[0035] The function of the diverging lens 6 is to make the light distribution on the light energy meter probe more uniform, so as to avoid inaccurate probe measurement due to excessive local concentration of light intensity.

[0036] The function of the fixed optical attenuator 13 is to reduce the laser pulse energy, further reducing the pulse energy entering the laser rangefinder receiver, with attenuation ratios of 100 times and 10,000 times.

[0037] The function of the fiber collimator 9 is to collimate the laser in the fiber into parallel light. The Thorlabs RC08FC-P01 reflective collimator is selected, which has a protective silver film and an FC / PC interface.

[0038] The 50:50 beam splitter 10 is a Thorlabs BSW29R ultraviolet fused silica flat beam splitter.

[0039] The function of the converging lens 11 is to reduce the diameter of the laser beam, increase the optical power per unit area, and make it easier for the photodetector to detect weak optical signals.

[0040] The function of the pentagonal prism 15 is to adjust the position of the emitted laser to match the receiving window of the laser rangefinder. Its advantage is that the emission angle is only related to the incident angle and will not change with the rotation of the prism. It adopts Thorlabs CC M1-PS932 / M, material N-BK7, and the reflective film is an aluminum film with chromium-nickel-iron alloy and black paint protective layer.

[0041] A method for testing the performance of a laser rangefinder includes the following steps:

[0042] Step 1: Adjust the position of each optical component to align the optical path;

[0043] Place the laser rangefinder inside the device, adjust the relative position of the laser rangefinder and the optical system, start the laser rangefinder to emit a laser, and make the laser incident at 45° onto the 99:1 beam splitter 1. Then adjust the position of the pentagonal prism 15 so that its emitted light is aligned with the receiving window of the laser rangefinder.

[0044] Step 2: Detection of laser energy parameters;

[0045] Based on the specifications of the laser rangefinder, adjust the parameters of the optical energy meter 16 and oscilloscope 17, observe the parameters of the optical energy meter 16, and fine-tune the position of the laser rangefinder according to the displayed parameters to maximize the displayed parameters. After reaching the maximum value, fix the position of the laser rangefinder. The laser energy parameters are:

[0046]

[0047] η tx η represents the transmittance of the laser rangefinder transmitter. split The beam splitter ratio is 99:1, and E1 is the parameter displayed on the light energy meter.

[0048] Step 3: Testing the receiver sensitivity of the laser rangefinder;

[0049] Seal the device, and use heating wire 19 and cooling plate 20 to adjust the internal temperature of the device to the required simulated ambient temperature. Adjust the adjustable light attenuator 4 to the maximum attenuation value, turn on the laser rangefinder to emit laser light, and slowly adjust the adjustable light attenuator 4 while observing the laser rangefinder until it reaches the critical value that can measure distance. Record the critical voltage value V2 using oscilloscope 17, and calculate the received power of photodetector 12 by combining it with the responsivity R of photodetector 12.

[0050]

[0051] The receiver sensitivity of the laser rangefinder is:

[0052]

[0053] Where η rx η represents the transmittance of the laser rangefinder receiver. fixed2 To fix the attenuation rate of optical attenuator 213.

[0054] Example: Simulates the detection of laser energy parameters and receiver sensitivity of a laser rangefinder under weather conditions of 35°C.

[0055] A method for testing the performance of a laser rangefinder, comprising the following steps:

[0056] Step 1: Adjust the position of each optical component to align the optical path;

[0057] Place the laser rangefinder inside the device, adjust the relative position of the laser rangefinder and the optical system, start the laser rangefinder to emit a laser, and make the laser incident at 45° onto the 99:1 beam splitter 1. Then adjust the position of the pentagonal prism 15 so that its emitted light is aligned with the receiving window of the laser rangefinder.

[0058] Step 2: Detection of laser energy parameters;

[0059] Based on the specifications of the laser rangefinder, adjust the parameters of the optical energy meter 16 and oscilloscope 17, observe the parameters of the optical energy meter 16, and fine-tune the position of the laser rangefinder according to the displayed parameters to maximize the displayed parameters. After reaching the maximum value, fix the position of the laser rangefinder. The laser energy parameters are:

[0060]

[0061] η tx η represents the transmittance of the laser rangefinder transmitter. split The beam splitter ratio is 99:1, and E1 is the parameter displayed on the light energy meter.

[0062] In this invention, the 99:1 beam splitter is a fractional beam ratio of 1 to η. split The transmittance η of the laser rangefinder transmitter is 0.99. tx The value is 0.8. In the example, E1 = 100mJ, so E = 12.5J.

[0063] Step 3: Detection of receiver sensitivity;

[0064] Seal the device and use heating wire 19 to raise the internal temperature to 35°C as detected by temperature and humidity sensor 18. Adjust the adjustable light attenuator 4 to its maximum attenuation value, turn on the laser rangefinder to emit laser light, and slowly adjust the adjustable light attenuator 4 while observing the laser rangefinder until it reaches the critical value that can measure distance. Record the critical voltage value V2 using oscilloscope 17, and calculate the received power of photodetector 12 by combining it with the responsivity R of photodetector 12.

[0065]

[0066] In the embodiment, let: V2 = 10 -3 V, R = 10 4 V / W, then P = 10 -7 W.

[0067] The receiver sensitivity of the laser rangefinder is:

[0068]

[0069] Where η rx η represents the transmittance of the laser rangefinder receiver. fixed2 To fix the attenuation rate of optical attenuator 213.

[0070] In the embodiment, let: E1 = 100mJ = 0.1J, η split =0.99=0.99, η fixed2 =0.01, η rx =0.85, η tx =0.8, V2=10 -3V, R = 10 4 V / W.

[0071] Except for E1 = 100mJ = 0.1J, V2 = 10 -3 V, R = 10 4 Except for the V / W parameter, which is a measured value, all other parameters are fixed values.

[0072] After substituting the values ​​into the formula, P is obtained. min =8.5×10 -10 W, E = 12.5 J, meaning the receiver sensitivity of the laser rangefinder is 8.5 × 10⁻⁶ J at an ambient temperature of 35°C. -10 W, the laser energy of the laser rangefinder is 12.5J. The results show that the present invention makes full use of a single laser source, simplifies the measurement process of the laser rangefinder's receiving sensitivity, and makes the detection results more convenient and intuitive.

Claims

1. A performance testing device for a laser rangefinder, characterized in that, The device includes: a 99:1 beam splitter (1), a total reflection mirror (2), a fixed optical attenuator (3), an adjustable optical attenuator (4), an optical fiber coupler (5), a diverging lens (6), a light energy meter probe (7), a single-mode optical fiber (8), an optical fiber collimator (9), a 50:50 beam splitter (10), a converging lens (11), a photodetector (12), a fixed optical attenuator (2) (13), a total reflection mirror (2) (14), a pentagonal prism (15), a light energy meter head (16), an oscilloscope (17), a temperature and humidity sensor (18), a heating wire (19), a cooling chip (20), and a housing (21). The 99:1 beam splitter (1) is placed at a 45° angle to the laser incident direction. The 99:1 beam splitter (1), the diverging lens (6), and the optical energy meter probe (7) are placed coaxially. The total reflection mirror (2) is placed at a 45° angle to the laser incident direction. The total reflection mirror (2), the fixed optical attenuator (3), the adjustable optical attenuator (4), and the fiber coupler (5) are placed coaxially. The fiber coupler (5) is connected to the single-mode fiber (8), and the single-mode fiber (8) is connected to the fiber collimator (9). The optical axes of the fiber coupler (5) and the fiber collimator (9) are parallel. The 50:50 beam splitter (10) is placed at a 45° angle to the laser incident direction. The fiber collimator (9), 50:50 beam splitter (10), fixed optical attenuator II (13) and total reflection mirror II (14) are placed coaxially. The total reflection mirror II (14) is placed at a 45° angle to the laser incident direction. The 50:50 beam splitter (10), converging lens (11) and photodetector (12) are placed coaxially. The photodetector (12) is connected to the oscilloscope (17). The light energy meter probe (7) is connected to the light energy meter head (16). The light energy meter head (16) and oscilloscope (17) are fixed on the outer wall of the housing. The temperature and humidity sensor (18), heating wire (19) and cooling chip (20) are all fixed on the inner wall of the housing (21).

2. The laser rangefinder performance testing device according to claim 1, characterized in that, The laser rangefinder emits a laser beam through its emission window, which is incident on a 99:1 beam splitter (1). The 99:1 beam splitter (1) splits the laser energy into two parts. The 1% portion of the light passes through a diverging lens (6) and is received by a light energy meter probe (7) to measure the laser energy. The 99% portion of the light is reflected by a total reflection mirror (2). The reflected light passes through a fixed optical attenuator (3) and an adjustable optical attenuator (4) in sequence to attenuate the laser energy. The attenuated light is coupled into a single-mode fiber (8) through a fiber coupler (5). The outgoing light from the single-mode fiber enters a fiber collimator (9) for collimation. The collimated light is split into two parts by a 50:50 beam splitter (10). One part of the light passes through a converging lens (10) and is then split into two parts. 11) The light is focused onto the photodetector (12) to measure the receiving sensitivity. Another part of the light is attenuated by the fixed optical attenuator (13) and then reflected by the total reflection mirror (14). The reflected light passes through the pentaprism (15) and is then incident on the receiving window of the laser rangefinder for distance measurement. The energy detected by the light energy meter probe (7) is displayed by the light energy meter head (16). The data detected by the photodetector (12) is displayed by the oscilloscope (17) for data analysis. The temperature and humidity sensor (18) is used to detect and obtain the temperature and humidity information inside the device. The heating wire (19) is used to raise the temperature inside the device. The cooling chip (20) is used to lower the temperature inside the device.

3. The laser rangefinder performance testing device according to claim 1, characterized in that, The 99:1 beam splitter (1) uses ordinary uncoated BK7 glass.

4. The laser rangefinder performance testing device according to claim 1, characterized in that, The fixed optical attenuator (3) consists of multiple sets of neutral density filters to reduce laser pulse energy and prevent damage to downstream components.

5. The laser rangefinder performance testing device according to claim 1, characterized in that, The adjustable optical attenuator (4) employs two polarizers. The beam energy is attenuated by adjusting the polarization angle of the rear polarizer relative to the front polarizer, satisfying Malus's law I=I0cos 2 θ, where I0 is the initial light intensity, θ is the angle between the two polarizers, and I is the light intensity after passing through the attenuator. The two polarizers of the adjustable light attenuator (4) are marked with angles respectively.

6. The laser rangefinder performance testing device according to claim 1, characterized in that, The fixed optical attenuator 2 (13) has attenuation ratios of 100 times and 10000 times.

7. A method for testing the performance of a laser rangefinder, characterized in that, The method includes the following steps: Step 1: Adjust the position of each optical component to align the optical path; Place the laser rangefinder inside the device, adjust the relative position of the laser rangefinder and the optical system, start the laser rangefinder to emit laser, and make the laser incident at 45° onto the 99:1 beam splitter (1). Then adjust the position of the pentagonal prism (15) so that the emitted light is aligned with the receiving window of the laser rangefinder. Step 2: Detection of laser energy parameters; According to the specifications of the laser rangefinder, adjust the parameters of the optical energy meter (16) and oscilloscope (17), observe the parameters of the optical energy meter (16), and fine-tune the position of the laser rangefinder according to the displayed parameters to maximize the displayed parameters. After reaching the maximum value, fix the position of the laser rangefinder. The laser energy parameters are: η tx η represents the transmittance of the laser rangefinder transmitter. split The beam splitting ratio is 99:1 for the beam splitter (1), and E1 is the parameter displayed on the light energy meter. Step 3: Testing the receiver sensitivity of the laser rangefinder; Seal the device and use heating wire (19) and cooling plate (20) to adjust the temperature inside the device to the required simulated ambient temperature. Adjust the adjustable light attenuator (4) to the maximum attenuation value, turn on the laser rangefinder to emit laser light, slowly adjust the adjustable light attenuator (4), and observe the laser rangefinder until it reaches the critical value that can measure distance. Record the critical voltage value V2 using an oscilloscope (17), and calculate the received power of the photodetector (12) in conjunction with the responsivity R of the photodetector (12): The receiver sensitivity of the laser rangefinder is: Where η rx η represents the transmittance of the laser rangefinder receiver. fixed2 The attenuation rate of fixed optical attenuator 2 (13) is determined.

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