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CN-116265876-B - Pulse detection system and method

CN116265876BCN 116265876 BCN116265876 BCN 116265876BCN-116265876-B

Abstract

The invention provides a pulse detection system and a pulse detection method. The pulse detection system comprises a laser module, an average power detection module, a peak power detection module, a control module and a power supply module, wherein the laser module is used for emitting laser and comprises a laser and at least one switch, the average power detection module is used for detecting the average voltage of a plurality of pulses and generating a first detection result, the peak power detection module is used for detecting the peak voltage of a single pulse and generating a second detection result, the control module is used for carrying out data processing according to the first detection result and the second detection result and outputting corresponding signals, the corresponding signals are used for controlling the on-off of the switch, and the power supply module is used for providing electric energy for the operation of the system. The invention can realize the simultaneous detection of the peak power and the average power of the pulse circuit and improve the safety of the pulse detection system.

Inventors

  • YU YONGTAO
  • ZHU MENGQI
  • HOU QINGJIAO
  • WANG BINGJIE

Assignees

  • 宁波舜宇车载光学技术有限公司

Dates

Publication Date
20260505
Application Date
20211216

Claims (20)

  1. 1. A pulse detection system, comprising: the laser module is used for emitting laser and comprises a laser, a first switch and a second switch; the average power detection module is used for detecting the average voltage of the plurality of pulses and generating a first detection result; The peak power detection module is used for detecting the peak voltage of the single pulse and producing a second detection result; the control module is used for carrying out data processing according to the first detection result and/or the second detection result and outputting corresponding signals; The power module is used for providing electric energy for the operation of the detection system; The first switch is arranged between the power supply module and the first end of the laser, and the second switch is arranged at the second end of the laser; the corresponding signals comprise a first pulse sequence signal and a control signal, wherein the control signal is used for controlling the on-off of the first switch, the first pulse sequence signal is used for controlling the on-off of the second switch, or The corresponding signals comprise a first pulse sequence signal, a second pulse sequence signal and a control signal, wherein the control signal is used for controlling the on-off of the first switch, the first pulse sequence signal is used for controlling the on-off of the second switch, the second pulse sequence signal is used for controlling the working state of a chopper circuit, and the chopper circuit is used for regulating the voltage output by the power supply module and regulating the voltage output by the power supply to be smaller than a safety threshold voltage.
  2. 2. The pulse detection system of claim 1, wherein the control module comprises a first functional unit and a second functional unit, the first functional unit is configured to output the first pulse sequence, and adjust a duty cycle of the first pulse sequence according to detection results of the peak power detection module and the average power detection module, so that the laser operates in a safe range, and the second functional unit is configured to output a control signal of the first switch to turn on or off the laser.
  3. 3. The pulse detection system of claim 1, further comprising a temperature detection module electrically connected to the control module for detecting a temperature change around the laser and outputting a detection result to the control module; the control module further comprises a fourth functional unit for reading the temperature around the laser and outputting a power control signal to output a first safety threshold for controlling the average power detection module and a second safety threshold for controlling the peak power detection module.
  4. 4. The pulse detection system of claim 3, wherein the temperature detection module comprises a thermistor or a temperature sensor chip.
  5. 5. The pulse detection system of claim 1, further comprising a current sensor between the power module and the average power detection module, the current sensor configured to detect a change in current in the circuit and convert the current change into a voltage change, such that a dc level emitted by the power module is converted into a pulse signal to facilitate detection of average power.
  6. 6. The pulse detection system of claim 5, wherein the current sensor is a current sense resistor.
  7. 7. The pulse detection system of claim 1, wherein the laser module comprises an energy storage capacitor for storing charge to compensate for a moment of circuit conduction of the laser module and to timely illuminate the laser.
  8. 8. The pulse detection system of claim 1, wherein, The control module further comprises a third functional unit, when detecting that the peak power and/or the average power exceeds a safety threshold, the third functional unit is used for outputting a second pulse sequence signal so as to enable the voltage output by the power supply module to fall within the safety threshold.
  9. 9. The pulse detection system of claim 1, wherein the first switch comprises a field effect transistor, a triode, or a digital gate.
  10. 10. The pulse detection system of claim 1, further comprising a driving circuit coupled to the second switch, the driving circuit configured to boost a voltage and a current of the first pulse train signal to control a fast turn-on and turn-off of the second switch, the driving circuit comprising a digital buffer chip or a transistor driver chip.
  11. 11. The pulse detection system of claim 1, wherein the average power detection module and the peak power detection module are electrically connected to the control module via an analog-to-digital conversion circuit, respectively; The control module further comprises a fifth functional unit, wherein the fifth functional unit is used for adjusting the first safety threshold value and the second safety threshold value in real time and comparing the detected output result with the corresponding safety threshold value.
  12. 12. The pulse detection system of claim 11, wherein the average power detection module comprises a first portion of an RC circuit and an analog-to-digital conversion circuit, the peak power detection module comprises a second portion of the analog-to-digital conversion circuit, and the first safety threshold and the second safety threshold are disposed in the control module.
  13. 13. The pulse detection system of claim 1, wherein the average power detection module and the peak power detection module are each electrically connected to the control module via a comparator circuit.
  14. 14. The pulse detection system of claim 13, wherein the average power detection module comprises an RC circuit and a first comparator, a positive input of the first comparator coupled to an output of the RC circuit, and a negative input of the first comparator coupled to a first safety threshold.
  15. 15. The pulse detection system of claim 13, wherein the peak power detection module comprises a second comparator, a positive input of the second comparator is coupled to the second switch, and a negative input of the second comparator is coupled to a second safety threshold.
  16. 16. The pulse detection system of claim 1, wherein the control module comprises a counter unit, and the control module controls the counter unit to start counting when the peak voltage of the single pulse exceeds a preset voltage threshold according to the second detection result, and controls the first switch to be turned off when the count value of the counter unit is greater than a preset number threshold.
  17. 17. The pulse detection system of claim 1, wherein the second switch is a high frequency switch transistor comprising an N-MOS transistor, a GaN transistor, a power transistor, or an insulated gate bipolar transistor.
  18. 18. A pulse detection method, characterized in that a pulse detection system according to any one of claims 1-17 is used, said method comprising the steps of: the laser module emits laser light; the average power detection module detects average voltages of a plurality of pulses and generates a first detection result; the peak power detection module detects the peak voltage of the single pulse and generates a second detection result; the control module performs data processing according to the first detection result and/or the second detection result and outputs corresponding signals; The corresponding signals comprise a first pulse sequence signal and a control signal, wherein the control signal is used for controlling the on-off of the first switch, the first pulse sequence signal is used for controlling the on-off of the second switch, or The corresponding signals comprise a first pulse sequence signal, a second pulse sequence signal and a control signal, wherein the control signal is used for controlling the on-off of the first switch, the first pulse sequence signal is used for controlling the on-off of the second switch, the second pulse sequence signal is used for controlling the working state of a chopper circuit, and the chopper circuit is used for regulating the voltage output by the power supply module and regulating the voltage output by the power supply to be smaller than a safety threshold voltage.
  19. 19. The pulse detection method of claim 18, wherein the control module receives the first detection result and the second detection result and performs data processing, the method comprising the steps of: The control module judges whether the peak voltage in the current pulse exceeds a second safety threshold according to a second detection result, and judges whether the average voltage of the laser in a plurality of pulses exceeds the first safety threshold according to the first detection result; when the first detection result is judged to exceed the first safety threshold value and/or the second detection result is judged to exceed a second safety threshold value; the control module outputs a first control signal to disconnect the first switch, and the laser is closed.
  20. 20. The pulse detection method of claim 19, wherein when it is determined that the peak voltage in the previous pulse exceeds the first safety threshold, the method comprises the steps of: the counter of the control module starts counting; And when the count value of the counter exceeds the set value of the safety pulse number, the control module outputs the first control signal, and the laser is turned off.

Description

Pulse detection system and method Technical Field The invention relates to the technical field of lasers, in particular to a pulse detection system and a pulse detection method. Background In the prior art, laser radar systems measure the distance to the target using the time required for the pulsed laser to travel between objects, but very low laser energy exposure can also cause damage to the cornea or retina of the eye. The safety laser standards commonly used internationally at present are the International electrotechnical Commission standard (IEC 60825) and the American national standards institute standard (ANSI Z136), wherein the standards are specified that 1, the radiation amount of any single pulse in a pulse sequence does not exceed the maximum radiation amount of a single pulse, and 2, the average radiation amount of a plurality of pulses in any duration T should not exceed the maximum radiation amount of the continuous irradiation time T of the single pulse in the pulse beam. The related products at present are more concerned about the overall performance of the products, the development cost and the failure probability are comprehensively considered, the common technology is to monitor the average power in a specific time in a pulse sequence, the principle is to conduct integral sampling on the working current of the laser, the sampled signals are converted into direct current level signals in a period of time, and finally when the direct current level exceeds a safety threshold value, the master switch is controlled to stop the laser from emitting light. However, based on the standard of eye safety, real-time power detection of any pulse is an essential item, which is a trend of future development, and if only average power is detected, the standard may not be passed. In the prior art, the setting of the safety threshold is a fixed value, but the photoelectric conversion efficiency, peak current, on-voltage drop, on-resistance of the switching device and the like of the actual laser all change along with the change of temperature, and the working currents at the same luminous power and different temperatures are different, so the safety threshold should be adjusted in real time based on the surrounding environment temperature. Disclosure of Invention Aiming at the problems in the prior art, the invention aims to provide a pulse detection system and a pulse detection method, which can realize the detection of peak power and average power of a pulse circuit at the same time and improve the use precision and the safety of the pulse detection system. The embodiment of the invention provides a pulse detection system which comprises a laser module, an average power detection module, a peak power detection module, a control module and a power supply module, wherein the laser module is used for emitting laser and comprises a laser and at least one switch, the average power detection module is used for detecting average voltage of a plurality of pulses and generating a first detection result, the peak power detection module is used for detecting peak voltage of a single pulse and generating a second detection result, the control module is used for carrying out data processing according to the first detection result and/or the second detection result and outputting corresponding signals, and the corresponding signals are used for controlling on-off of the switch, and the power supply module is used for providing electric energy for the detection system. In some embodiments, the laser module includes a first switch disposed between the power module and a first end of the laser and a second switch disposed at a second end of the laser. In some embodiments, the respective signals include a first pulse sequence signal for controlling the on-off of the first switch and a control signal for controlling the on-off of the second switch. In some embodiments, the control module includes a first functional unit and a second functional unit, where the first functional unit is configured to output the first pulse sequence, and adjust a duty cycle of the first pulse sequence according to detection results of the peak power detection module and the average power detection module, so that the laser operates in a safe range, and the second functional unit is configured to output a control signal of the first switch to turn on or off the laser. In some embodiments, the laser also comprises a temperature detection module, wherein the temperature detection module is electrically connected with the control module and is used for detecting the temperature change around the laser and outputting a detection result to the control module; the control module further comprises a fourth functional unit for reading the temperature around the laser and outputting a power control signal to output a first safety threshold for controlling the average power detection module and a second safety threshold for controlling the peak power d