High-reliability laser protection circuit
By combining modular design with energy storage modules, reliable protection for the MOPA laser under abnormal power outage conditions is achieved, ensuring that the laser starts and stops in the correct sequence. This solves the problem of unreliable timing in existing technologies and improves the reliability and versatility of the laser.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- BEIJING INST OF AEROSPACE CONTROL DEVICES
- Filing Date
- 2025-12-30
- Publication Date
- 2026-04-21
AI Technical Summary
Existing MOPA laser protection circuits suffer from strong software timing dependence, lack of hardware logic feedback, and lack of dynamic operating timing protection, resulting in unreliable start-stop timing and damage to the laser due to loss of timing during abnormal power outages.
A highly reliable laser protection circuit with a modular design is adopted. It combines software and hardware timing logic control, introduces an energy storage module to ensure that the seed source and amplification stage are powered off in sequence during abnormal power failure, and monitors the laser status in real time and generates drive signals through a monitoring module to achieve closed-loop control.
It improves the reliability of lasers in complex electromagnetic environments and long-term operation, ensures that lasers start and stop in the correct sequence under any operating conditions to avoid damage, provides short-term power-on protection, reduces circuit complexity and improves versatility.
Smart Images
Figure CN121906356A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a highly reliable laser protection circuit, belonging to the field of optoelectronic technology design. Background Technology
[0002] MOPA (Master Vibrating Power Amplifier) lasers, due to their flexible and adjustable output pulse parameters and high peak power, have become the core light source for high-end industrial manufacturing and cutting-edge scientific devices. In industrial applications, MOPA lasers have deeply penetrated new energy battery manufacturing, semiconductor and microelectronics packaging, aerospace, and automotive fields; in scientific research and special applications, MOPA lasers can be used in lidar systems, quantum precision measurement, cold atom physics experiments, and optical communication. However, its unique discrete seed source and amplification stage structure, while bringing advantages, also places stringent requirements on the system's control reliability. This structure requires strict timing logic during start-up and shutdown: upon power-up, the seed source must start before the pre-amplification stage, and the main amplification stage must start last; upon power-down, the main amplification stage must turn off first, and the seed source must turn off last. Currently, the mainstream solutions for achieving this timing control have significant technical vulnerabilities, mainly reflected in: (1) Over-reliance on software timing: Currently, most systems use microcontrollers to generate delays through software programming to control start and stop timing. When this method encounters unexpected situations such as program crashes, strong electromagnetic interference, or power fluctuations, the control unit may be reset, leading to disordered output logic and thus generating incorrect drive signals; (2) Lack of feedback in hardware logic: Some solutions use simple hardware delays, which do not rely on software, but the control logic is "open-loop". If the seed source or pre-amplification stage fails, the amplification stage will still turn on blindly, causing the protection mechanism to fail; (3) The existing protection mechanism has blind spots: Traditional laser protection circuits focus on monitoring parameters such as overcurrent, overvoltage, and overheating, but lack special protection for dynamic working timing. Once the timing is out of control, the amplification stage will work in a high-gain state without seed light input, which will cause self-excited oscillation or optical surge, instantly generating huge pulse energy, which may cause irreversible physical damage to the optical system. Summary of the Invention
[0003] The technical problem solved by this invention is: in the existing MOPA laser protection circuit, the start-stop timing is unreliable due to reliance on software timing or simple hardware delay, and abnormal power failure during light output leads to loss of shutdown timing, which in turn causes damage to the laser. A highly reliable laser protection circuit is proposed.
[0004] The present invention solves the above-mentioned technical problem through the following technical solution: A high-reliability laser protection circuit includes a power supply module, an energy storage module, a control module, a monitoring module, a logic processing module, and a drive module, wherein: The energy storage module is used to control the seed source and amplification stage to be powered off sequentially in the event of an abnormal power outage. The power module connects to the energy storage module and supplies power to each module. The control module, connected to the logic processing module and the monitoring module, is used to receive laser operating commands and output preset sorted enable signals to the logic processing module. The monitoring module, connected to the control module and logic processing module, monitors the output power of the seed source and each stage of the amplifier, is used to determine the laser's light output status, and serves as the input signal for the logic processing module. The logic processing module combines the input signal sent by the monitoring module with the enable signal sent by the control module to form a drive signal and outputs it to the drive module. The drive signal is generated according to the preset order of the enable signals. The driver module receives the drive signal and generates a constant current power supply signal to drive the seed source and various stages of the laser amplifier.
[0005] The power supply module provides power to each module by converting the input DC voltage.
[0006] The energy storage module includes a control energy storage unit, a seed source energy storage unit, and an amplification stage energy storage unit. The control energy storage unit is used to control the seed source, the seed source energy storage unit corresponding to each amplification stage, and the amplification stage energy storage unit to complete the power outage in the normal power outage sequence when there is an abnormal power outage. The seed source energy storage unit is used to supply energy to the seed source when there is an abnormal power outage, and the amplification stage energy storage unit is used to supply energy to each amplification stage when there is an abnormal power outage. The amplification stage includes a main amplification stage and a pre-amplification stage. The main amplification stage has no energy storage unit, while the pre-amplification stage has a corresponding energy storage unit.
[0007] The enable signal output by the control module is generated in a preset order according to the laser operating command type and receiving order; the enable signal includes the main amplification stage enable signal, the pre-amplification stage enable signal, and the seed source enable signal.
[0008] The enable signal is processed by a preset algorithm within the logic processing module to generate a drive signal after participating in logical operations.
[0009] The monitoring module acquires real-time status information and performs logical operations on it simultaneously with the enable signal output by the control module within the logic processing module, generating a drive signal based on the result of the logical operations.
[0010] After receiving the drive signal, the drive module generates a constant current power signal and transmits it to the laser to achieve start-stop control.
[0011] The drive module controls the output according to an external enable signal. When the external enable signal is turned on, the drive module outputs a constant current power signal to control the laser to start working; when the external enable signal is turned off, the drive module stops outputting the constant current power signal, and the laser stops working.
[0012] A control method based on a high-reliability laser protection circuit includes: When the laser starts working, the control module outputs the seed source and the enable signals of each amplification stage in a preset order; The seed source enable signal enhances the driving capability through the logic processing module and is directly output as the driving signal of the seed source driving module. The monitoring module monitors the output power of the seed source. When the output power is normal, the monitoring module outputs a signal indicating that the seed source is working normally. The monitoring module also monitors the output power of the pre-amplification stage. When the output power is normal, the monitoring module outputs a signal indicating that the pre-amplification stage is working normally. In the logic processing module, the pre-amplifier stage enable signal, the main amplifier stage enable signal, and the pre-amplifier stage normal operation signal are processed by "AND" and then output as the enable signal for the main amplifier stage driving module. When the laser stops working, the control module outputs the seed source and the power-disabling signals of each amplification stage in a preset sequence. When the laser seed source or pre-amplification stage is abnormally shut down, the monitoring module outputs an abnormal power signal. Following the AND logic, it works with the energy storage module to sequentially cut off power, stop light output, and realize the laser protection function.
[0013] When the laser stops working, the main control module outputs the seed source and the power-off signals of each amplification stage in sequence. First, it outputs the power-off signal of the main amplification stage. After the monitoring module detects that there is no output from the main amplification stage, it outputs the power-off signal of the pre-amplification stage. After the monitoring module detects that there is no output from the pre-amplification stage, it outputs the power-off signal of the seed source.
[0014] The advantages of this invention compared to the prior art are: (1) The present invention provides a high-reliability laser protection circuit. The timing logic control module is constructed by combining software and hardware to eliminate the risk of timing loss caused by software or hardware control alone, improve the reliability in complex electromagnetic environment or long-term operation, and solve the timing control problem under normal operation. Furthermore, by introducing an independent energy storage power supply module, it provides short-term power supply for each stage of drive after power failure, ensuring that the laser can first shut down the amplification stage and then shut down the seed source, effectively solving the timing protection problem under the extreme working condition of abnormal power failure, and realizing full working condition protection; (2) The present invention adopts a dual protection mechanism that combines main control timing logic control and passive energy storage power failure protection to improve the reliability of laser use. The control adopts a "closed-loop" control thinking, taking the working status of the previous stage such as seed source and pre-amplification stage as the basis for whether the next stage is turned on. If the previous stage cannot start normally due to fault, the next stage will also be prohibited from being turned on, upgrading from simple "delay protection" to "state protection". (3) The present invention adopts a modular design concept. The seed source and each amplification stage adopt independent energy storage and driving design, which can reduce circuit complexity and facilitate maintenance. At the same time, the circuit can be easily expanded according to the actual number of amplification stages, and can be flexibly adapted to lasers with different response characteristics by adjusting the delay parameters, which has strong versatility. Attached Figure Description
[0015] Figure 1 A logic block diagram of the high-reliability laser protection circuit provided by the present invention; Figure 2 This is a schematic diagram of the structure of the high-reliability laser protection circuit provided by the present invention. Detailed Implementation
[0016] A highly reliable laser protection circuit includes a power supply module, an energy storage module, a control module, a monitoring module, a logic processing module, and a drive module. The circuit is simple in composition and enables the seed source and each stage of the amplifier to switch on and off in sequence when the MOPA laser emits light, shuts down, or experiences an abnormal power failure, thereby protecting the laser. At the hardware level, it can force the correct start-up and shutdown sequence of the seed source, pre-amplifier stage, and main amplifier stage under any operating condition, fundamentally eliminating control timing errors and improving the reliability of laser use.
[0017] The high-reliability laser protection circuit, with each module designed as follows: The energy storage module is used to control the seed source and amplification stage to be powered off sequentially in the event of an abnormal power outage. The power module connects to the energy storage module and supplies power to each module. The control module, connected to the logic processing module and the monitoring module, is used to receive laser operating commands and output preset sorted enable signals to the logic processing module. The monitoring module, connected to the control module and logic processing module, monitors the output power of the seed source and each stage of the amplifier, is used to determine the laser's light output status, and serves as the input signal for the logic processing module. The logic processing module combines the input signal sent by the monitoring module with the enable signal sent by the control module to form a drive signal and outputs it to the drive module. The drive signal is generated according to the preset order of the enable signals. The driver module receives the drive signal and generates a constant current power supply signal to drive the seed source and various stages of the laser amplifier.
[0018] The power supply module provides power to each module by converting the input DC voltage.
[0019] The energy storage module includes a control energy storage unit, a seed source energy storage unit, and an amplification stage energy storage unit. The control energy storage unit is used to control the seed source, the seed source energy storage units corresponding to each amplification stage, and the amplification stage energy storage units to complete the power outage in the normal power outage sequence when an abnormal power outage occurs. The seed source energy storage unit is used to supply energy to the seed source when an abnormal power outage occurs, and the amplification stage energy storage unit is used to supply energy to each amplification stage when an abnormal power outage occurs.
[0020] The enable signal output by the control module generates preset sorted enable signals based on the laser's operating command type and receiving order.
[0021] The enable signal is processed by the logic processing module through a preset algorithm and then used to generate a drive signal.
[0022] The monitoring module acquires real-time status information and performs logical operations on it simultaneously with the enable signal output by the control module within the logic processing module, generating a drive signal based on the result of the logical operation.
[0023] After receiving the drive signal, the drive module generates a constant current power signal and transmits it to the laser to realize the start and stop control.
[0024] The drive module controls the output based on the external enable signal. When the external enable signal is turned on, the drive module outputs a constant current power signal to control the laser to start working; when the external enable signal is turned off, the drive module stops outputting the constant current power signal, and the laser stops working.
[0025] The control method for achieving a high-reliability laser protection circuit involves the following steps: When the laser starts working, the control module outputs the seed source and the enable signals of each amplification stage in a preset order; The seed source enable signal enhances the driving capability through the logic processing module and is directly output as the driving signal of the seed source driving module. The monitoring module monitors the output power of the seed source. When the output power is normal, the monitoring module outputs a signal indicating that the seed source is working normally. The monitoring module also monitors the output power of the pre-amplification stage. When the output power is normal, the monitoring module outputs a signal indicating that the pre-amplification stage is working normally. In the logic processing module, the pre-amplifier stage enable signal, the main amplifier stage enable signal, and the pre-amplifier stage normal operation signal are processed by "AND" and then output as the enable signal for the main amplifier stage driving module. When the laser stops working, the control module outputs the seed source and the power-disabling signals of each amplification stage in a preset sequence. When the laser seed source or pre-amplification stage is abnormally shut down, the monitoring module outputs an abnormal power signal. Following the AND logic, it works with the energy storage module to sequentially cut off power, stop light output, and realize the laser protection function.
[0026] When the laser stops working, the main control module outputs the seed source and the power-off signals of each amplification stage in sequence. First, it outputs the power-off signal of the main amplification stage. After the monitoring module detects that there is no output from the main amplification stage, it outputs the power-off signal of the pre-amplification stage. After the monitoring module detects that there is no output from the pre-amplification stage, it outputs the power-off signal of the seed source.
[0027] The following description, in conjunction with the accompanying drawings and preferred embodiments, provides further details: In the current embodiment, a high-reliability laser protection circuit is applied to an MOPA laser that includes a seed source laser and at least one optical amplification stage. The circuit includes: a power supply module, an energy storage module, a control module, a logic processing module, a drive module, and a monitoring module.
[0028] like Figure 1 As shown, the power module is connected to the energy storage module, and the externally input DC power is converted by the power module to power the circuit. The energy storage module is connected to the power supply module and includes a main control module, a monitoring module, a logic processing module energy storage unit, a seed source drive energy storage unit, and a pre-amplification stage drive energy storage unit. When the laser experiences an abnormal power outage, the main amplification stage, lacking an energy storage unit, will be shut down due to the momentary power failure. The pre-amplification stage, equipped with a smaller energy storage unit, can maintain light output briefly. The seed source, equipped with a larger energy storage unit, can maintain light output for a longer period. The control module, monitoring module, and logic processing module, each equipped with the largest energy storage unit, continue operating until the seed source depletes its energy storage and shuts down. This achieves abnormal power failure protection.
[0029] The control module is connected to the logic processing module and the monitoring module, receives laser operating commands, and outputs enable signals; the main control module also reads monitoring information from the monitoring module and reports the laser's operating status. The monitoring module is connected to the control module and the logic processing module. It monitors the output power of the seed source and each amplification stage, and completes the analog signal sampling and transmission to the control module. At the same time, it generates signal levels that characterize the working status of the seed source and each amplification stage, which serve as inputs for the logic processing module. The logic processing module is connected to the control module and the monitoring module, receives input signals from the control module and the monitoring module, and realizes the coordinated output of the seed source and the drive signals of each amplification stage. Its logic configuration is as follows: (1) When the laser starts working, the main control module outputs the seed source and each amplification stage enable signals in sequence. The seed source enable signal is enhanced by the logic processing module and then directly output as the drive signal for the seed source drive module. At the same time, the monitoring module monitors the output power of the seed source. When the output power is normal, the monitoring module outputs a seed source working normally signal. The seed source enable signal, the pre-amplification stage enable signal, and the seed source working normally signal are processed by the logic processing module and then output as the enable signal for the pre-amplification stage drive module. At the same time, the monitoring module monitors the output power of the pre-amplification stage. When the output power is normal, the monitoring module outputs a pre-amplification stage working normally signal. The pre-amplification stage enable signal, the main amplification stage enable signal, and the pre-amplification stage working normally signal are processed by the logic processing module and then output as the enable signal for the main amplification stage drive module.
[0030] (2) When the laser stops working, the main control module outputs the seed source and the power-off signals of each amplification stage in sequence; first, it outputs the power-off signal of the main amplification stage; after the monitoring module detects that the main amplification stage has no output, it outputs the power-off signal of the pre-amplification stage; after the monitoring module detects that the pre-amplification stage has no output, it outputs the power-off signal of the seed source.
[0031] (3) When the laser seed source or pre-amplification stage is abnormally turned off, the monitoring module will output an abnormal output power signal of that stage. The subsequent drive signal will also disappear due to the AND logic, and stop the light output, thus realizing the laser protection function. The logic processing module is composed of pure hardware circuits, ensuring that its operation does not depend on software programs; The monitoring module includes an analog-to-digital converter unit and a comparator unit. The output of the analog-to-digital converter unit is used to control the module to monitor the operating status, and the output of the comparator unit (high and low level) is used as input to the logic processing module.
[0032] Example 1: like Figure 2 As shown, a high-reliability laser protection circuit includes: a power supply module 1, an energy storage module 2, a control module 3, a monitoring module 4, a logic processing module 5, and a drive module 6; the power supply module 1 is connected to the energy storage module 2; the energy storage module 2 is connected to the control module 3, the monitoring module 4, the logic processing module 5, and the drive module 6; the control module 3 is connected to the monitoring module 4 and the logic processing module 5; the logic processing module 5 is connected to the drive module 6; the power supply module 1, the energy storage module 2, the control module 3, the monitoring module 4, the logic processing module 5, and the drive module 6 are placed inside the circuit housing 7 and connected to a seed source laser diode (LD) 8, an amplification stage 1 laser diode 9, an amplification stage 2 laser diode 10, and a photodetector 11.
[0033] The energy storage module can be configured arbitrarily according to the number of laser amplification stages, and the energy storage capacity can be adjusted according to the power of the seed source LD8 and the amplification stages LD9 and 10 to adapt to lasers of different power and applications. The control module 3 can set the number of output enable signals according to the actual situation to expand the number of laser amplification stages; The photoelectric detector 11 connected to the monitoring module 4 can be configured according to the actual situation to improve the reliability of the protection. The drive signal output by logic processing module 5 can be increased or decreased according to the actual seed source and number of amplification stages used; The output current of the drive module 6 can be adjusted arbitrarily within a certain range to adjust the laser output power according to the usage requirements; In this embodiment, the protection circuit further includes a communication unit and an enable signal indication unit. The communication unit and the enable signal indication unit are connected to the control module 2. The communication unit can receive laser operating commands and report the operating status of the protection circuit; the enable signal indication unit can observe the enable signal status.
[0034] The laser protection circuit proposed in this embodiment integrates active timing control and passive power-down protection, enabling the seed source and amplifiers at each stage to sequentially switch on and off when the MOPA laser emits light, shuts off light, or experiences an abnormal power outage, thereby protecting the laser and improving its reliability.
[0035] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.
[0036] The contents not described in detail in this specification are common knowledge to those skilled in the art.
Claims
1. A highly reliable laser protection circuit, characterized in that: It includes a power supply module, an energy storage module, a control module, a monitoring module, a logic processing module, and a drive module, among which: The energy storage module is used to control the seed source and amplification stage to be powered off sequentially in the event of an abnormal power outage. The power module connects to the energy storage module and supplies power to each module. The control module, connected to the logic processing module and the monitoring module, is used to receive laser operating commands and output preset sorted enable signals to the logic processing module. The monitoring module, connected to the control module and logic processing module, monitors the output power of the seed source and each stage of the amplifier, is used to determine the laser's light output status, and serves as the input signal for the logic processing module. The logic processing module combines the input signal sent by the monitoring module with the enable signal sent by the control module to form a drive signal and outputs it to the drive module. The drive signal is generated according to the preset order of the enable signals. The driver module receives the drive signal and generates a constant current power supply signal to drive the seed source and various stages of the laser amplifier.
2. The high-reliability laser protection circuit according to claim 1, characterized in that: The power supply module provides power to each module by converting the input DC voltage.
3. The high-reliability laser protection circuit according to claim 1, characterized in that: The energy storage module includes a control energy storage unit, a seed source energy storage unit, and an amplification stage energy storage unit. The control energy storage unit is used to control the seed source, the seed source energy storage unit corresponding to each amplification stage, and the amplification stage energy storage unit to complete the power outage in the normal power outage sequence when there is an abnormal power outage. The seed source energy storage unit is used to supply energy to the seed source when there is an abnormal power outage, and the amplification stage energy storage unit is used to supply energy to each amplification stage when there is an abnormal power outage. The amplification stage includes a main amplification stage and a pre-amplification stage. The main amplification stage has no energy storage unit, while the pre-amplification stage has a corresponding energy storage unit.
4. The high-reliability laser protection circuit according to claim 3, characterized in that: The enable signal output by the control module is generated in a preset order according to the laser operating command type and receiving order; the enable signal includes the main amplification stage enable signal, the pre-amplification stage enable signal, and the seed source enable signal.
5. A high-reliability laser protection circuit according to claim 4, characterized in that: The enable signal is processed by a preset algorithm within the logic processing module to generate a drive signal after participating in logical operations.
6. A high-reliability laser protection circuit according to claim 5, characterized in that: The monitoring module acquires real-time status information and performs logical operations on it simultaneously with the enable signal output by the control module within the logic processing module, generating a drive signal based on the result of the logical operations.
7. A high-reliability laser protection circuit according to claim 6, characterized in that: After receiving the drive signal, the drive module generates a constant current power signal and transmits it to the laser to achieve start-stop control.
8. A high-reliability laser protection circuit according to claim 7, characterized in that: The drive module controls the output according to an external enable signal. When the external enable signal is turned on, the drive module outputs a constant current power signal to control the laser to start working; when the external enable signal is turned off, the drive module stops outputting the constant current power signal, and the laser stops working.
9. A control method for implementing a high-reliability laser protection circuit according to claim 8, characterized in that... include: When the laser starts working, the control module outputs the seed source and the enable signals of each amplification stage in a preset order; The seed source enable signal enhances the driving capability through the logic processing module and is directly output as the driving signal of the seed source driving module. The monitoring module monitors the output power of the seed source. When the output power is normal, the monitoring module outputs a signal indicating that the seed source is working normally. The monitoring module also monitors the output power of the pre-amplification stage. When the output power is normal, the monitoring module outputs a signal indicating that the pre-amplification stage is working normally. In the logic processing module, the pre-amplifier stage enable signal, the main amplifier stage enable signal, and the pre-amplifier stage normal operation signal are processed by "AND" and then output as the enable signal for the main amplifier stage driving module. When the laser stops working, the control module outputs the seed source and the power-disabling signals of each amplification stage in a preset sequence. When the laser seed source or pre-amplification stage is abnormally shut down, the monitoring module outputs an abnormal power signal. Following the AND logic, it works with the energy storage module to sequentially cut off power, stop light output, and realize the laser protection function.
10. The control method for implementing the high-reliability laser protection circuit according to claim 9, characterized in that: When the laser stops working, the main control module outputs the seed source and the power-off signals of each amplification stage in sequence. First, it outputs the power-off signal of the main amplification stage. After the monitoring module detects that there is no output from the main amplification stage, it outputs the power-off signal of the pre-amplification stage. After the monitoring module detects that there is no output from the pre-amplification stage, it outputs the power-off signal of the seed source.