System and method for realizing controllable laser dazzling based on modulation microsecond pulse

Abstract

The invention relates to a system for realizing controllable laser dazzling based on modulated microsecond pulses, which comprises a laser modulation module and a safety control module which are arranged in a shell, the laser modulation module comprises a laser, a first signal generator, a polarizer, an electro-optical modulator, a second signal generator and an optical beam expanding system, and the safety control module comprises a laser range finder, an illuminometer and a self-adaptive control unit. The laser modulation module is sequentially provided with a laser, a first signal generator, a polarizer, an electro-optical modulator, a second signal generator and an optical beam expanding system along a laser propagation path, and the self-adaptive control unit is connected with the laser, the first signal generator, the second signal generator, a driving motor of the optical beam expanding system and the laser range finder. The system and the method for realizing the controllable laser dazzling based on the modulated microsecond pulse have the advantages of reversible dazzling, high safety and strong environmental adaptability.

Description

Technical Field

[0001] The present invention relates to the technical field of laser applications, and particularly to the field of laser dazzlers, specifically to a system and method for achieving controllable laser dazzling based on modulated microsecond pulses. Background Art

[0002] Currently, most laser dazzlers use continuous lasers, and the dazzling effect on the human eye depends on the average laser energy. Since the dazzler cannot cause permanent damage to the human eye, the laser energy must be less than the maximum allowable exposure. Therefore, the dazzling effect of continuous laser-based dazzlers is limited, and there is a risk of permanent retinal damage caused by energy accumulation. Pulsed lasers with nanosecond and shorter pulse widths can cause thermo-mechanical damage and non-linear effects, while modulated microsecond pulse lasers have a higher dazzling effect at the same energy and are not easily to cause permanent damage to the human eye. Currently, a dazzler based on modulated microsecond pulse lasers has not been invented. Summary of the Invention

[0003] The purpose of the present invention is to overcome the above-mentioned drawbacks of the prior art, and provide a system and method for achieving controllable laser dazzling based on modulated microsecond pulses that meet the requirements of high safety, strong environmental adaptability, and a relatively wide range of applications.

[0004] In order to achieve the above purpose, the system and method for achieving controllable laser dazzling based on modulated microsecond pulses of the present invention are as follows:

[0005] The system for achieving controllable laser dazzling based on modulated microsecond pulses is mainly characterized in that the system includes a laser modulation module and a safety control module. The laser modulation module and the safety control module are installed in a housing. The laser modulation module includes a laser, a first signal generator, a polarizer, an electro-optic modulator, a second signal generator, and an optical beam expander system. The safety control module includes a laser rangefinder, an illuminometer, and an adaptive control unit.

[0006] The laser modulation module sequentially installs a laser, a first signal generator, a polarizer, an electro-optic modulator, a second signal generator, and an optical beam expander system along the laser propagation path. The adaptive control unit is connected to the laser, the first signal generator, the second signal generator, the drive motor of the optical beam expander system, and the laser rangefinder for real-time signal feedback and parameter regulation. The laser rangefinder is connected to the adaptive control unit, and the illuminometer is connected to the adaptive control unit.

[0007] Preferably, the laser is triggered to control the laser output by the TTL signal generated by the first signal generator, and the frequency and duty cycle of the modulation signal are changed. The polarizer receives the modulated laser and transmits the laser to the electro-optic modulator. The electro-optic modulator is triggered and controlled by the second signal generator, and the duty cycle of the trigger signal is changed.

[0008] Preferably, the illuminometer collects the ambient illuminance value and transmits the illuminance value to the adaptive control unit. The adaptive control unit divides the glare mode into day or night mode according to the illuminance value.

[0009] Preferably, the adaptive control unit receives the target distance information obtained by the laser rangefinder, calculates and outputs the laser energy through the adaptive power adjustment algorithm and the hierarchical response function, and adjusts the input current of the laser.

[0010] Preferably, the adaptive control unit obtains the laser current value in real time. If the current value exceeds the safety threshold, the adaptive control unit issues an abort signal to synchronously abort the laser output.

[0011] Preferably, the laser energy is calculated and output through the adaptive power adjustment algorithm, specifically as follows:

[0012] The laser power required at the target is obtained according to the target position, ambient illuminance and gear, and the laser power at the transmitting end is calculated, specifically as follows:

[0013] The laser power at the transmitting end is calculated according to the following formula:

[0014] P0 = P·(π·(d·cosθ / 2) 2 )·e αd ;

[0015] where P0 is the laser power density at the transmitting end, P is the laser power density at the target, d is the target distance, θ is the divergence angle, and α is the atmospheric attenuation constant.

[0016] Preferably, the optical beam expander system emits modulated laser and adjusts the beam divergence angle through the driving motor. The angle of the beam divergence angle is 0.5 to 5 mrad.

[0017] Preferably, the laser uses a semiconductor laser. The wavelength of the semiconductor laser is 532 nm, and the laser output power is adjusted by changing the input current of the laser.

[0018] The method for realizing controllable laser glare by using the above system is mainly characterized in that the method includes the following steps:

[0019] (1) The illuminometer detects the ambient illuminance, and the adaptive control unit distinguishes between day or night mode;

[0020] (2) The laser rangefinder measures the target distance and calculates the safe laser power;

[0021] (3) The first signal generator and the second signal generator adjust the laser pulse width, repetition frequency, flashing frequency and duty cycle to generate low-frequency flashing microsecond pulses;

[0022] (4) The optical beam expander system dynamically adjusts the divergence angle to control the spot coverage range;

[0023] (5) The input current of the laser is monitored in real time. If the input current exceeds the safe threshold, the output is immediately aborted.

[0024] The system and method for realizing controllable laser dazzling based on modulated microsecond pulses of the present invention solve the problems of insufficient dazzling effect of traditional continuous lasers and high damage risk, and have the advantages of reversible dazzling, high safety and strong environmental adaptability. Description of the Drawings

[0025] Figure 1 It is a structural block diagram of the system for realizing controllable laser dazzling based on modulated microsecond pulses of the present invention.

[0026] Reference Signs:

[0027] 1 Laser

[0028] 2 First Signal Generator

[0029] 3 Polarizer

[0030] 4 Electro-optic Modulator

[0031] 5 Second Signal Generator

[0032] 6 Fiber Optic Patch Cord

[0033] 7 Optical Beam Expander System

[0034] 8 Adaptive Control Unit

[0035] 9 Laser Rangefinder

[0036] 10 Illuminometer

[0037] 11 Gear Controller Detailed Embodiments

[0038] In order to be able to more clearly describe the technical content of the present invention, the following will be further described in conjunction with specific embodiments.

[0039] The system for realizing controllable laser dazzling based on modulated microsecond pulses of the present invention includes a laser modulation module and a safety control module. The laser modulation module and the safety control module are installed in a housing. The laser modulation module includes a laser 1, a first signal generator 2, a polarizer 3, an electro-optic modulator 4, a second signal generator 5, and an optical beam expander system 7. The safety control module includes a laser rangefinder 9, an illuminometer 10, and an adaptive control unit 8.

[0040] In the laser modulation module, the laser 1, the first signal generator 2, the polarizer 3, the electro-optic modulator 4, the second signal generator 5, and the optical beam expander system 7 are sequentially installed along the laser propagation path. The adaptive control unit 8 is connected to the laser 1, the first signal generator 2, the second signal generator 5, the drive motor of the optical beam expander system 7, and the laser rangefinder 9 for real-time signal feedback and parameter regulation. The laser rangefinder 9 is connected to the adaptive control unit 8, and the illuminometer 10 is connected to the adaptive control unit 8.

[0041] As a preferred embodiment of the present invention, the laser 1 is triggered by the TTL signal generated by the first signal generator 2 to control the laser output, and the frequency and duty cycle of the modulation signal are changed. The polarizer 3 receives the modulated laser and transmits the laser to the electro-optic modulator 4. The electro-optic modulator 4 is triggered and controlled by the second signal generator 5, and the duty cycle of the trigger signal is changed.

[0042] As a preferred embodiment of the present invention, the illuminometer 10 collects the ambient illuminance value and transmits the illuminance value to the adaptive control unit. The adaptive control unit divides the dazzling mode into a daytime or nighttime mode according to the illuminance value.

[0043] As a preferred embodiment of the present invention, the adaptive control unit 8 receives the target distance information obtained by the laser rangefinder 9, calculates and outputs the laser energy through an adaptive power adjustment algorithm and a hierarchical response function, and adjusts the input current of the laser 1.

[0044] As a preferred embodiment of the present invention, the adaptive control unit 8 obtains the current value of the laser 1 in real time. If the current value exceeds the safety threshold, the adaptive control unit 8 issues an abort signal to synchronously abort the laser output.

[0045] As a preferred embodiment of the present invention, calculating and outputting the laser energy through the adaptive power adjustment algorithm is specifically as follows:

[0046] Obtain the required laser power at the target according to the target position, ambient illuminance, and gear, and calculate the laser power at the transmitting end. Specifically:

[0047] Calculate the laser power at the transmitting end according to the following formula:

[0048] P0 = P·(π·(d·cosθ / 2) 2 )·e αd ;

[0049] Wherein, P0 is the laser power density at the transmitting end, P is the laser power density at the target, d is the target distance, θ is the divergence angle, and α is the atmospheric attenuation constant.

[0050] As a preferred embodiment of the present invention, the optical beam expander system 7 emits modulated laser light, and the beam divergence angle is adjusted by a drive motor, and the angle of the beam divergence angle is 0.5 - 5 mrad.

[0051] As a preferred embodiment of the present invention, the laser 1 adopts a semiconductor laser, the wavelength of the semiconductor laser is 532 nm, and the laser output power is adjusted by changing the input current of the laser 1.

[0052] The method for realizing controllable laser dazzling by using the above system according to the present invention includes the following steps:

[0053] (1) The illuminometer 10 detects the ambient illuminance, and the adaptive control unit 8 distinguishes between day or night modes;

[0054] (2) The laser rangefinder 9 measures the target distance and calculates the safe laser power;

[0055] (3) The first signal generator 2 and the second signal generator 5 adjust the laser pulse width, repetition frequency and duty cycle to generate low-frequency flashing microsecond pulses;

[0056] (4) The optical beam expander system 7 dynamically adjusts the divergence angle to control the spot coverage range;

[0057] (5) The input current of the laser 1 is monitored in real time. If the input current exceeds the safety threshold, the output is immediately aborted.

[0058] In the specific embodiment of the present invention, a controllable laser dazzling device and method based on modulated microsecond pulses are disclosed, which relates to the technical field of laser applications. The device includes a laser modulation module and a safety control module. The microsecond pulse laser is generated by a 532 nm semiconductor laser 1 and a signal generator. The pulse width (20 - 500 μs) and repetition frequency (10 - 100 kHz) are adjusted by the signal generator, and the flashing frequency (5 - 20 Hz) and duty cycle (5% - 90%) are adjusted by the electro-optic modulator 4 and the signal generator, combined with the optical beam expander system 7 to dynamically adjust the divergence angle (0.5 - 5 mrad). The safety control module realizes hierarchical response (warning, dazzling, aborting) through laser ranging, ambient illuminance detection and adaptive algorithm to ensure that the output power density meets the human eye safety standard.

[0059] The object of the present invention is to provide a modulated microsecond pulsed laser dazzler, which can accurately control laser parameters such as pulse width, repetition frequency, duty cycle, divergence angle, etc., can identify day and night environments, respond in a graded manner, achieve a reversible dazzling effect, and reduce the risk of permanent damage while ensuring the deterrent effect.

[0060] Figure 1 In the figure, the dashed line represents a communication connection, and the solid line represents an optical path. The controllable laser dazzler device based on modulated microsecond pulses of the present invention is contained in a housing, and the housing contains a laser modulation module and a safety control module. The laser modulation module sequentially includes a laser 1, a first signal generator 2, a polarizer 3, an electro-optic modulator 4, a second signal generator 5, and an optical beam expander system 7 along the laser propagation path. The safety control module includes a laser rangefinder 9, an illuminometer 10, and an adaptive control unit 8. The illuminometer 10 is installed at the top of the housing, and the whole illuminometer 10 is inside the housing. There is a window at the corresponding position on the top of the housing for receiving external environmental light.

[0061] The adaptive control unit 8 is connected to the laser 1, the first signal generator 2, the second signal generator 5, the drive motor 7 of the optical beam expander system 7, the laser rangefinder 9, and the illuminometer 10 to realize real-time signal feedback and parameter regulation.

[0062] The laser 1 uses a semiconductor laser 1 with a wavelength of 532 nm as the laser source, and the output power of the laser is adjusted by changing the input current of the laser 1. The frequency and duty cycle of the trigger signal are adjusted by the first signal generator 2 to output a microsecond pulsed laser with a pulse width of 20 - 500 μs and a repetition frequency of 10 - 100 kHz.

[0063] The electro-optic modulator 4 adjusts the frequency and duty cycle of the trigger signal through the second signal generator 5 to generate a microsecond pulsed laser with a modulation frequency of 5 - 20 Hz and a low-frequency flashing duty cycle.

[0064] The modulated laser of the present invention is emitted through the optical beam expander system 7. The optical beam expander system 7 is controlled by a drive motor to achieve adjustable beam divergence angle. The optical beam expander system 7 adjusts the beam divergence angle to 0.5 - 5 mrad through the drive motor.

[0065] The illuminometer 10 of the present invention collects the environmental illuminance value and transmits the illuminance value to the adaptive control unit 8. The adaptive control unit 8 divides the dazzling mode into a day or night mode according to the illuminance value.

[0066] The laser 1 of the present invention is connected to a first signal generator 2, and the TTL signal generated by the first signal generator 2 is used to trigger and control the laser output. By changing the frequency and duty cycle of the modulation signal, the repetition frequency and pulse width of the laser can be adjusted. The preliminarily modulated laser passes through a polarizer 3 and enters an electro-optic modulator 4. The electro-optic modulator 4 is triggered and controlled by a second signal generator 5. By changing the frequency and duty cycle of the trigger signal, the flicker frequency and duty cycle of the microsecond pulsed laser can be adjusted.

[0067] The safety control module of the present invention selects a 1550 nm laser rangefinder 9, which can accurately measure the distance information of the irradiated target. The target distance information obtained by the laser rangefinder 9 is transmitted to the adaptive control unit 8. Through the adaptive power adjustment algorithm (including parameters such as the maximum allowable exposure of the human eye, distance, divergence angle, and ambient illuminance) and the hierarchical response function, the output laser energy is calculated, and the input current of the laser 1 is adjusted according to the calculation result to achieve effective and safe and controllable dazzling laser output. The adaptive control unit 8 continuously obtains the current value of the laser 1. When the current value exceeds the safety threshold, the adaptive control unit 8 issues an abort signal to synchronously abort the laser output.

[0068] The laser dazzling device of the present invention has a hierarchical response function:

[0069] Level 1 warning: The output power density is 200 μW / cm 2 (during the day), 100 μW / cm 2 (at night), and the flicker frequency is 5 Hz;

[0070] Level 2 dazzling: The output power density is 800 μW / cm 2 (during the day), 400 μW / cm 2 (at night), and the flicker frequency is 10 Hz;

[0071] Level 3 abort: When the power density exceeds 800 μW / cm 2 the adaptive control unit 8 aborts the laser output.

[0072] The adaptive power adjustment algorithm is:

[0073] P0 = P·(π·(d·cosθ / 2) 2 )·e αd

[0074] where P0 is the laser power density at the transmitting end, P is the laser power density at the target, d is the target distance, θ is the divergence angle, and α is the atmospheric attenuation constant.

[0075] A controllable laser dazzling method based on modulated microsecond pulses includes the following steps:

[0076] (1) Detect the ambient illuminance through the illuminometer 10, and the adaptive control unit 8 distinguishes between day or night modes;

[0077] (2) The laser rangefinder 9 measures the target distance, and combines the divergence angle, ambient illuminance, and the human eye safety threshold to calculate the safe laser power;

[0078] (3) The first signal generator 2 and the second signal generator 5 adjust the laser pulse width, repetition frequency, flash frequency, and duty cycle to generate low-frequency flashing microsecond pulses;

[0079] (4) The optical beam expander system 7 dynamically adjusts the divergence angle to control the spot coverage range;

[0080] (5) Monitor the input current of the laser 1 in real time. If it exceeds the safety threshold, immediately abort the output.

[0081] The parameter adjustment range of the parameter modulation module of the present invention is as follows:

[0082] Pulse width: 20 - 500 μs; Pulse repetition frequency: 10 - 100 kHz; Modulation (flash) frequency: 5 - 20 Hz; Modulation duty cycle: 5% - 90%; Divergence angle: 0.5 - 5 mrad.

[0083] The specific operation steps of Embodiment 1 of the present invention are as follows:

[0084] 1. After starting the device, the illuminometer 10 detects the ambient light intensity and determines it as the day mode;

[0085] 2. The laser rangefinder 9 measures the target distance to be 80 meters. The adaptive control unit 8 sets the gear as the first-level warning according to the gear set by the gear controller 11, and the required power density is 200 μW / cm 2 ;

[0086] 3. The first signal generator 2 sets the pulse width to 200 μs and the repetition frequency to 50 kHz. The second signal generator 5 adjusts the duty cycle to 30% and the flash frequency to 5 Hz;

[0087] 4. The optical beam expander system 7 adjusts the divergence angle to 2 mrad, and the output beam covers the target area;

[0088] 5. When the target approaches to 30 meters, the adaptive control unit 8 triggers the second-level dazzling mode, and the power density is increased to 800 μW / cm 2 , and the flash frequency is increased to 10 Hz;

[0089] 6. If the input current abnormally increases, the adaptive control unit 8 immediately cuts off the laser output and enters the third-level abort state.

[0090] The present invention further includes the step of calculating the peak power, specifically:

[0091]

[0092] where P p is the peak power, and adjusting the current of laser 1 can change the peak power; P0 is the laser power density at the transmitting end, T p is the pulse width; R is the repetition frequency; D is the duty cycle; S0 is the spot size at the transmitting end.

[0093] For the specific implementation solution of this embodiment, reference can be made to the relevant descriptions in the above embodiments, which will not be elaborated here.

[0094] It can be understood that the same or similar parts in the above embodiments can be referred to each other, and the content not detailed in some embodiments can be referred to the same or similar content in other embodiments.

[0095] It should be noted that in the description of the present invention, terms such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of the present invention, unless otherwise specified, the meaning of "a plurality of" refers to at least two.

[0096] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0097] The system and method for realizing controllable laser dazzling based on modulated microsecond pulses of the present invention solve the problems of insufficient dazzling effect and high damage risk of traditional continuous lasers, and have the advantages of reversible dazzling, high safety, and strong environmental adaptability.

[0098] In this specification, the present invention has been described with reference to its specific embodiments. However, it is obvious that various modifications and transformations can still be made without departing from the spirit and scope of the present invention. Therefore, the specification and drawings should be regarded as illustrative rather than restrictive.

Claims

1. A system for achieving controllable laser dazzling based on modulating microsecond pulses, characterized in that, The described system includes a laser modulation module and a safety control module. The laser modulation module and the safety control module are installed in a housing. The laser modulation module includes a laser, a first signal generator, a polarizer, an electro-optic modulator, a second signal generator, and an optical beam expander system. The safety control module includes a laser rangefinder, an illuminometer, and an adaptive control unit. The laser modulation module sequentially installs a laser, a first signal generator, a polarizer, an electro-optic modulator, a second signal generator, and an optical beam expander system along the laser propagation path. The adaptive control unit is connected to the laser, the first signal generator, the second signal generator, the drive motor of the optical beam expander system, and the laser rangefinder for real-time signal feedback and parameter regulation. The laser rangefinder is connected to the adaptive control unit, and the illuminometer is connected to the adaptive control unit.

2. The system for realizing controllable laser dazzling based on modulating microsecond pulses according to claim 1, wherein The laser is triggered by a TTL signal generated by the first signal generator to control the laser output, changing the frequency and duty cycle of the modulation signal. The polarizer receives the modulated laser and transmits the laser to the electro-optic modulator. The electro-optic modulator is triggered and controlled by the second signal generator, and the duty cycle of the trigger signal is changed.

3. The system for achieving controllable laser dazzling based on modulating microsecond pulses according to claim 1, characterized in that, The illuminometer collects the ambient illuminance value and transmits the illuminance value to the adaptive control unit. The adaptive control unit classifies the glare mode into a daytime or nighttime mode according to the illuminance value.

4. The system for realizing controllable laser dazzling based on modulating microsecond pulses according to claim 1, wherein The adaptive control unit receives the target distance information obtained by the laser rangefinder, calculates and outputs the laser energy through an adaptive power adjustment algorithm and a hierarchical response function, and adjusts the input current of the laser.

5. The system for realizing controllable laser dazzling based on modulating microsecond pulses according to claim 1, wherein The adaptive control unit obtains the laser current value in real time. If the current value exceeds the safety threshold, the adaptive control unit issues an abort signal to synchronously abort the laser output.

6. The system for realizing controllable laser dazzling based on modulating microsecond pulses according to claim 4, wherein The calculation of the output laser energy through the adaptive power adjustment algorithm is specifically as follows: Obtain the required laser power at the target according to the target position, ambient illuminance, and gear, and calculate the laser power at the transmitting end, specifically: Calculate the laser power at the transmitting end according to the following formula: P0 = P·(π·(d·cosθ / 2) 2 )·e αd ; Where, P0 is the laser power density at the transmitting end, P is the laser power density at the target, d is the target distance, θ is the divergence angle, and α is the atmospheric attenuation constant.

7. The system for realizing controllable laser dazzling based on modulating microsecond pulses according to claim 1, wherein The optical beam expander system emits modulated laser and adjusts the beam divergence angle through a drive motor. The angle of the beam divergence angle is 0.5 - 5 mrad.

8. The system for realizing controllable laser dazzling based on modulating microsecond pulses according to claim 1, characterized in that, The laser uses a semiconductor laser. The wavelength of the semiconductor laser is 532 nm, and the laser output power is adjusted by changing the input current of the laser.

9. A method for realizing controllable laser dazzling based on the system according to claim 1, characterized in that, The method includes the following steps: (1) The illuminometer detects the ambient illuminance, and the adaptive control unit differentiates between the daytime or nighttime mode; (2) The laser rangefinder measures the target distance and calculates the safe laser power; (3) The first signal generator and the second signal generator adjust the laser pulse width, repetition frequency, flash frequency, and duty cycle to generate low-frequency flashing microsecond pulses; (4) The optical beam expander system dynamically adjusts the divergence angle to control the spot coverage range; (5) Monitor the input current of the laser in real time. If the input current exceeds the safety threshold, immediately abort the output.

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