Laser circuit with overcurrent protection circuit and overcurrent protection system

Abstract

The utility model provides a kind of laser circuit and overcurrent protection system with overcurrent protection circuit, it is related to the technical field of voltage monitoring, the overcurrent protection execution unit is used to when the laser diode triggers overcurrent protection, disconnects loop current of laser diode current loop;The overcurrent detection module is used to detect loop current, and when the detection result is laser tube overcurrent, overcurrent trigger signal is sent to the anti-interference unit;The anti-interference unit is used to when receiving the overcurrent trigger signal, the overcurrent trigger signal is output to the signal holding unit by capacitor discharge;The signal holding unit is used to when receiving the overcurrent trigger signal output by anti-interference unit, low level signal is sent to the overcurrent protection execution unit, triggers the overcurrent protection state of the overcurrent protection execution unit.The utility model can reduce circuit complexity and circuit cost while significantly improving the overcurrent protection efficiency of laser tube.

Description

Technical Field

[0001] This utility model relates to the technical field of current detection, and in particular to a laser circuit and overcurrent protection system with an overcurrent protection circuit. Background Technology

[0002] Laser diodes can directly convert electrical energy into light energy, and have the characteristics of high brightness, high efficiency and long life. They have great potential in industrial fields as well as in rangefinders, lidar, communications and other fields. However, laser diodes have high requirements for voltage and current when used. A large current in a short period of time will cause a lot of heat to be generated inside the laser tube, which will lead to damage to the laser tube.

[0003] Currently, related technologies propose that during the use of laser tubes, the current of the laser tube can be detected in real time through peripheral control devices, AND gate circuits, and overcurrent protection chips. When an abnormal current exceeding the upper limit of use is detected, the laser tube can be shut down in time to ensure the service life of the laser tube. However, this solution has a high circuit complexity and cost, requires a certain detection time, and has a slow response to laser tube overcurrent. Utility Model Content

[0004] In view of this, the purpose of this utility model is to provide a laser circuit and overcurrent protection system with overcurrent protection circuit, which can significantly improve the overcurrent protection efficiency of laser tube while reducing circuit complexity and circuit cost.

[0005] In a first aspect, this utility model provides a laser circuit with an overcurrent protection circuit, comprising: a laser diode and an overcurrent protection circuit. The overcurrent protection circuit includes: an overcurrent protection execution unit, an overcurrent detection module, an anti-interference unit, and a signal holding unit. The overcurrent protection execution unit is connected to the laser diode and is used to disconnect the loop current of the laser diode current loop when the laser diode triggers overcurrent protection, thereby protecting the laser diode. The overcurrent detection module is connected to both the overcurrent protection execution unit and the anti-interference unit. The overcurrent detection module is used to detect the loop current of the laser diode current loop and, when the detection result indicates that the laser diode is overcurrent, sends an overcurrent trigger signal to the anti-interference unit. The anti-interference unit is connected to the signal holding unit and, upon receiving the overcurrent trigger signal, discharges through a capacitor to output the overcurrent trigger signal to the signal holding unit. The signal holding unit is also connected to the overcurrent protection execution unit and, upon receiving the overcurrent trigger signal output by the anti-interference unit, sends a low-level signal to the overcurrent protection execution unit to trigger the overcurrent protection state of the overcurrent protection execution unit.

[0006] In one embodiment, the laser circuit with overcurrent protection circuit further includes: a signal output unit; the signal output unit is connected to the overcurrent protection execution unit, and the signal output unit is used to send a high-level output signal to the overcurrent protection execution unit when powered on, so as to turn on the overcurrent protection execution unit, and when receiving an overcurrent trigger signal, it uses a first resistor to pull the output signal low, so as to send a low-level output signal to the overcurrent protection execution unit, so as to put the overcurrent protection execution unit into the overcurrent protection state.

[0007] In one embodiment, the signal holding unit includes: a first field-effect transistor, a first capacitor, and a second resistor; the second resistor is connected to the driving unit of the peripheral device and the first capacitor respectively, the first capacitor is connected to the first field-effect transistor, and the second resistor is used to continuously charge the first capacitor when the driving unit of the peripheral device is powered on, and to turn on the first field-effect transistor when the voltage across the first capacitor reaches the threshold voltage of the first field-effect transistor.

[0008] In one embodiment, the signal holding unit further includes a second field-effect transistor (FET); the second FET is used to cooperate with the first FET to control the working state of the signal holding unit. When both the first FET and the second FET are turned on, the signal holding unit is connected; when either the first FET or the second FET is turned off, the signal holding unit is disconnected.

[0009] In one embodiment, the anti-interference unit includes: a third resistor, a fourth resistor, a second capacitor, and a diode; the third resistor is connected to the first field-effect transistor and the second capacitor respectively, the second capacitor is connected to the second field-effect transistor, and the third resistor is used to continuously charge the second capacitor when the first field-effect transistor is turned on, and to turn on the second field-effect transistor when the voltage across the second capacitor reaches the threshold voltage of the second field-effect transistor; the fourth resistor is connected to the anode of the second field-effect transistor, the second capacitor, the third resistor, and the diode respectively, the cathode of the diode is connected to the overcurrent detection module, the fourth resistor is smaller than the third resistor, and the fourth resistor is used to cooperate with the third resistor to control the discharge of the second capacitor when the cathode of the diode receives an overcurrent trigger signal sent by the overcurrent detection module.

[0010] In one embodiment, the overcurrent protection execution unit includes: a third field-effect transistor; the third field-effect transistor turns on when it receives a high-level output signal, thereby connecting the laser diode current loop, and enters an overcurrent protection state when it receives a low-level output signal, thereby turning off the third field-effect transistor and disconnecting the laser diode current loop.

[0011] In one embodiment, the overcurrent detection module includes: a sampling unit; the sampling unit is connected to the laser diode current loop, and the sampling unit is used to convert the loop current of the laser diode current loop into a laser diode voltage signal, so as to perform overcurrent detection on the laser diode based on the laser diode voltage signal.

[0012] In one embodiment, the overcurrent detection module further includes a detection unit; the detection unit is connected to the sampling unit and the anti-interference unit respectively, and the detection unit is used to receive the laser diode voltage signal sent by the sampling unit and detect whether the laser diode voltage signal is overcurrent.

[0013] In one embodiment, the detection unit includes an RC module and a comparator. The input side of the comparator is connected to the RC module, and the output side is connected to the diode. The RC module is used to filter the received laser diode voltage signal. The comparator is used to compare the filtered voltage signal with a preset voltage to perform overcurrent detection on the laser diode.

[0014] Secondly, embodiments of the present invention also provide an overcurrent protection system for a laser tube, comprising: a laser circuit having an overcurrent protection circuit according to any of the first aspects, and a driving unit and a laser diode connected to the laser circuit having the overcurrent protection circuit.

[0015] The present invention provides the following beneficial effects: This utility model provides a laser circuit and overcurrent protection system with an overcurrent protection circuit, including: a laser diode and an overcurrent protection circuit. The overcurrent protection circuit includes: an overcurrent protection execution unit, an overcurrent detection module, an anti-interference unit, and a signal holding unit. The overcurrent protection execution unit is connected to the laser diode and is used to disconnect the loop current of the laser diode current loop when the laser diode triggers overcurrent protection, so as to protect the safety of the laser diode. The overcurrent detection module is connected to both the overcurrent protection execution unit and the anti-interference unit, and is used to detect the loop current of the laser diode current loop. When the detection result indicates that the laser tube is overcurrent, an overcurrent trigger signal is sent to the anti-interference unit. The anti-interference unit is connected to the signal holding unit. When the anti-interference unit receives the overcurrent trigger signal, it discharges the capacitor and outputs the overcurrent trigger signal to the signal holding unit. The signal holding unit is also connected to the overcurrent protection execution unit. When the signal holding unit receives the overcurrent trigger signal output by the anti-interference unit, it sends a low-level signal to the overcurrent protection execution unit to trigger the overcurrent protection state of the overcurrent protection execution unit. The above circuit can significantly improve the overcurrent protection efficiency of the laser tube while reducing circuit complexity and circuit cost.

[0016] Other features and advantages of this invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objectives and other advantages of this invention are realized and obtained through the structures particularly pointed out in the description, claims, and drawings.

[0017] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0018] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 A schematic diagram of an overcurrent protection circuit provided for an embodiment of this utility model; Figure 2 A schematic diagram of the specific structure of an overcurrent protection circuit provided in an embodiment of this utility model; Figure 3 A schematic diagram of another overcurrent protection circuit provided in this embodiment of the present invention; Figure 4 This is a schematic diagram of an overcurrent protection system for a laser tube provided in an embodiment of the present invention. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0021] Currently, related technologies suggest that laser diodes are semiconductor devices that can directly convert electrical energy into light energy. They feature high brightness, high efficiency, and long lifespan. Compared to LED laser diodes, all photons output by laser diodes are in phase, in direction, and of the same wavelength, resulting in highly concentrated energy. This allows laser diodes to output extremely high power density (power per unit area) at extremely small points (spots), with brightness far exceeding that of LEDs with equivalent electrical power. This is a core advantage for industrial applications such as laser cutting, marking, and engraving. Furthermore, lasers have very small divergence angles (typically within a few milliradians), and the beam propagates almost parallel, enabling transmission over long distances with minimal energy loss. This makes laser beams easy to precisely control and focus. Therefore, laser diodes also have enormous potential in rangefinders, lidar, communications (fiber optic communication, free-space optical communication), laser aiming, and optical storage (CD / DVD / Blu-ray). In addition, lasers have narrow spectral linewidths (extremely small wavelength range) and relatively pure colors, which are crucial for precise spectral analysis, interferometry, and biomedical imaging (such as confocal microscopy).

[0022] However, laser tubes have high requirements for voltage and current during use. A large current in a short period of time can cause a lot of heat to be generated inside the laser tube, which can lead to damage. Therefore, it is necessary to monitor the current of the laser tube in real time during use. Once an abnormal current exceeding the upper limit of use is detected, the laser tube needs to be shut down in time to ensure its service life. The present invention provides a laser circuit and overcurrent protection system with an overcurrent protection circuit, which can significantly improve the overcurrent protection efficiency of the laser tube while reducing circuit complexity and circuit cost.

[0023] To facilitate understanding of this embodiment, a laser circuit with overcurrent protection circuit disclosed in this utility model embodiment will first be described in detail.

[0024] See Figure 1 The diagram shows an overcurrent protection circuit. The laser circuit with the overcurrent protection circuit includes: a laser diode (LASER) and an overcurrent protection circuit. The overcurrent protection circuit includes: an overcurrent protection execution unit, an overcurrent detection module, an anti-interference unit, and a signal holding unit. The overcurrent protection actuator is connected to the laser diode. The overcurrent protection actuator is used to disconnect the loop current of the laser diode current loop when the laser diode triggers overcurrent protection, so as to protect the safety of the laser diode. The overcurrent detection module is connected to the overcurrent protection execution unit and the anti-interference unit respectively. The overcurrent detection module is used to detect the loop current of the laser diode current loop, and when the detection result is that the laser diode is overcurrent, it sends an overcurrent trigger signal to the anti-interference unit. The anti-interference unit is connected to the signal holding unit. When the anti-interference unit receives an overcurrent trigger signal, it discharges the capacitor and outputs the overcurrent trigger signal to the signal holding unit. The signal holding unit is also connected to the overcurrent protection execution unit. When the signal holding unit receives the overcurrent trigger signal output by the anti-interference unit, it sends a low-level signal to the overcurrent protection execution unit to trigger the overcurrent protection state of the overcurrent protection execution unit.

[0025] See Figure 2 The diagram shows a specific structure of an overcurrent protection circuit. Figure 3 The schematic diagram of another overcurrent protection circuit shown includes the following six units: Overcurrent Protection Execution Unit: When the system triggers overcurrent protection, this unit switches the main current circuit to protect the laser tube; Sampling Unit: This unit converts the laser tube circuit current into a voltage signal for subsequent detection unit to detect; Detection Unit: Determines whether there is an overcurrent by comparing the sampled unit signal with the set signal; Anti-interference Unit: Effectively isolates erroneous overcurrent signals caused by external electromagnetic interference or brief signal overshoot; Signal Holding Unit: Maintains a stable output signal after the overcurrent protection is triggered; Signal Output Unit: Outputs a control signal to cut off the laser tube current after the system overcurrent is triggered.

[0026] The laser circuit with overcurrent protection circuit also includes: a signal output unit, which includes: a first resistor (R1); the signal output unit is connected to the overcurrent protection execution unit, and the signal output unit is used to send a high-level output signal to the overcurrent protection execution unit when powered on, so that the overcurrent protection execution unit can be turned on, and when an overcurrent trigger signal is received, the first resistor is used to pull the output signal low, so as to send a low-level output signal to the overcurrent protection execution unit, so that the overcurrent protection execution unit enters the overcurrent protection state.

[0027] The signal holding unit includes: a first field-effect transistor (Q1), a first capacitor (C1), a second resistor (R2), and a second field-effect transistor (Q2). The second resistor is connected to the peripheral device's driving unit and the first capacitor, respectively. The first capacitor is connected to the first field-effect transistor. The second resistor is used to continuously charge the first capacitor when the peripheral device's driving unit is powered on. When the voltage across the first capacitor reaches the threshold voltage of the first field-effect transistor, the first field-effect transistor is turned on. The second field-effect transistor is used to work with the first field-effect transistor to control the working state of the signal holding unit. When both the first and second field-effect transistors are turned on, the signal holding unit is connected. When either the first or second field-effect transistor is turned off, the signal holding unit is disconnected.

[0028] The anti-interference unit includes: a third resistor (R3), a fourth resistor (R4), a second capacitor (C2), and a diode (D1); the third resistor is connected to the first field-effect transistor and the second capacitor respectively, and the second capacitor is connected to the second field-effect transistor. The third resistor is used to continuously charge the second capacitor when the first field-effect transistor is turned on, and to turn on the second field-effect transistor when the voltage across the second capacitor reaches the threshold voltage of the second field-effect transistor; the fourth resistor is connected to the anode of the second field-effect transistor, the second capacitor, the third resistor, and the diode respectively, and the cathode of the diode is connected to the overcurrent detection module. The fourth resistor is smaller than the third resistor. The fourth resistor is used to control the discharge of the second capacitor in coordination with the third resistor when the cathode of the diode receives the overcurrent trigger signal sent by the overcurrent detection module.

[0029] The overcurrent protection execution unit includes: a third field-effect transistor (Q3); the third field-effect transistor turns on when it receives a high-level output signal, thus connecting the laser diode current loop, and enters the overcurrent protection state when it receives a low-level output signal, turning off the third field-effect transistor to disconnect the laser diode current loop.

[0030] The overcurrent detection module includes a sampling unit; the sampling unit includes a fifth resistor (R5), the sampling unit is connected to the laser diode current loop, and the sampling unit is used to convert the loop current of the laser diode current loop into a laser diode voltage signal, so as to perform overcurrent detection on the laser diode based on the laser diode voltage signal.

[0031] The overcurrent detection module also includes a detection unit; the detection unit is connected to the sampling unit and the anti-interference unit respectively. The detection unit is used to receive the laser diode voltage signal sent by the sampling unit and to detect whether the laser diode voltage signal is overcurrent.

[0032] Furthermore, the detection unit includes: an RC module (third capacitor C3, sixth resistor R6) and a comparator. The input side of the comparator is connected to the RC module, and the output side is connected to the diode. The RC module is used to filter the received laser diode voltage signal. The comparator is used to compare the filtered voltage signal with a preset voltage to perform overcurrent detection on the laser diode.

[0033] In one implementation, the complete workflow of the above-mentioned unit is as follows: 1. After the system is powered on, the signal holding unit R2 charges the capacitor C1, which turns on Q1 and the output unit outputs a high-level signal.

[0034] 2. After Q1 is turned on, C3 is charged through R3. At this time, the comparator outputs a high level, and C3 will continue to charge until Q3 is turned on. At this time, the signal output unit has achieved a stable output of the output signal, the laser tube is turned on, and the equipment is working normally.

[0035] 3. When the detection unit detects an overcurrent condition through the sampling unit, the comparator outputs a low-level signal to the anti-interference unit.

[0036] 4. When the overcurrent trigger signal passes through the anti-interference unit, since R4 is less than R3, capacitor C3 is discharged. After the set discharge time (anti-interference process), the overcurrent trigger signal is output to the signal holding unit.

[0037] 5. After the signal holding unit receives the overcurrent trigger signal, the gate of Q3 is pulled low and Q3 is turned off, the gate of Q1 is pulled high and Q1 is turned off, and after being stabilized by the signal holding unit, it is sent to the overcurrent protection circuit execution unit through the output unit.

[0038] 6. After Q1 is turned off, the output signal of the signal output unit is pulled low due to the pull-down effect of R1.

[0039] 7. After receiving a low-level signal, the execution unit cuts off the laser tube current circuit to protect the laser tube.

[0040] 8. After the laser circuit is cut off, the comparator output bit is high level. Because of the unidirectional conductivity of the anti-interference unit (unit 4) D1, the gate of Q3 will still remain low level, thus ensuring the stable output of the overcurrent protection circuit.

[0041] 9. After power failure, power on again and repeat the above process.

[0042] The laser circuit with overcurrent protection circuit provided in this embodiment of the present invention has an anti-interference signal for its overcurrent protection signal, which can effectively avoid false triggering of the overcurrent state by external electromagnetic interference or the internal working state of the equipment. The signal holding circuit automatically sets the protection circuit to an unprotected state when powered on using a non-pull-up method, eliminating the need for AND gates and reducing the cost of peripheral components and circuits. In addition, it has an anti-interference mode. When external electromagnetic interference is severe or the laser in the equipment has a large current, the anti-interference function can effectively shield the overcurrent protection circuit from false triggering by non-actual overcurrent signals. Moreover, the sensitivity of the anti-interference function can be adjusted according to the actual usage situation. At the same time, it does not require the participation of other peripheral controllers. For example, in other existing solutions, the VM2 signal output by the controller is required to control the overcurrent detection circuit, which increases the complexity of the system.

[0043] Regarding the laser circuit with overcurrent protection circuit provided in the foregoing embodiments, this utility model embodiment also provides an overcurrent protection system for a laser tube, see [link to relevant documentation]. Figure 4 The diagram shows a structural schematic of an overcurrent protection system for a laser diode. The system includes the overcurrent protection circuit provided in the aforementioned embodiment, as well as a drive unit and a laser diode connected to the overcurrent protection circuit.

[0044] The laser circuit and overcurrent protection system with overcurrent protection circuit provided in this embodiment of the present invention use very few components to build a configurable delay and interference-proof low-level active overcurrent protection circuit. In the overcurrent protection of laser tubes and LEDs, DACs, microcontrollers or professional overcurrent protection chips are not used, which can reduce circuit cost and circuit complexity (no software involvement is required), while improving the real-time performance of the overcurrent protection circuit.

[0045] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working process of the laser circuit with overcurrent protection described above can be referred to the corresponding process in the foregoing embodiments, and will not be repeated here.

[0046] In the description of the embodiments of this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0047] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A laser circuit having an overcurrent protection circuit, characterized by comprising: include: A laser diode and an overcurrent protection circuit, wherein the overcurrent protection circuit includes: an overcurrent protection execution unit, an overcurrent detection module, an anti-interference unit, and a signal holding unit; The overcurrent protection execution unit is connected to the laser diode. The overcurrent protection execution unit is used to disconnect the loop current of the laser diode current loop when the laser diode triggers overcurrent protection, so as to protect the safety of the laser diode. The overcurrent detection module is connected to the overcurrent protection execution unit and the anti-interference unit respectively. The overcurrent detection module is used to detect the loop current of the laser diode current loop, and when the detection result is that the laser diode is overcurrent, it sends an overcurrent trigger signal to the anti-interference unit. The anti-interference unit is connected to the signal holding unit. When the overcurrent trigger signal is received, the anti-interference unit discharges the capacitor and outputs the overcurrent trigger signal to the signal holding unit. The signal holding unit is also connected to the overcurrent protection execution unit. When the signal holding unit receives the overcurrent trigger signal output by the anti-interference unit, it sends a low-level signal to the overcurrent protection execution unit to trigger the overcurrent protection state of the overcurrent protection execution unit.

2. The laser circuit having an overcurrent protection circuit according to claim 1, characterized by, The laser circuit with overcurrent protection circuit also includes: a signal output unit; The signal output unit is connected to the overcurrent protection execution unit. The signal output unit is used to send a high-level output signal to the overcurrent protection execution unit when powered on, so that the overcurrent protection execution unit can be turned on. When the overcurrent trigger signal is received, the output signal is pulled low by the first resistor so as to send the low-level output signal to the overcurrent protection execution unit, so that the overcurrent protection execution unit enters the overcurrent protection state.

3. The laser circuit with overcurrent protection circuit according to claim 1, characterized in that, The signal holding unit includes: a first field-effect transistor, a first capacitor, and a second resistor; The second resistor is connected to the peripheral device's driving unit and the first capacitor, respectively. The first capacitor is connected to the first field-effect transistor. The second resistor is used to continuously charge the first capacitor when the peripheral device's driving unit is powered on. When the voltage across the first capacitor reaches the threshold voltage of the first field-effect transistor, the first field-effect transistor is turned on.

4. The laser circuit having an overcurrent protection circuit according to claim 3, characterized by, The signal holding unit further includes: a second field-effect transistor; The second field-effect transistor is used to coordinate with the first field-effect transistor to control the working state of the signal holding unit. When both the first and second field-effect transistors are turned on, the signal holding unit is connected. When either the first or the second field-effect transistor is turned off, the signal holding unit is disconnected.

5. The laser circuit with overcurrent protection circuit according to claim 1, characterized in that, The anti-interference unit includes: a third resistor, a fourth resistor, a second capacitor, and a diode; The third resistor is connected to the first field-effect transistor and the second capacitor respectively. The second capacitor is connected to the second field-effect transistor. The third resistor is used to continuously charge the second capacitor when the first field-effect transistor is turned on. When the voltage across the second capacitor reaches the threshold voltage of the second field-effect transistor, the second field-effect transistor is turned on. The fourth resistor is connected to the anode of the second field-effect transistor, the second capacitor, the third resistor, and the diode, respectively. The cathode of the diode is connected to the overcurrent detection module. The fourth resistor is smaller than the third resistor. The fourth resistor is used to control the discharge of the second capacitor in conjunction with the third resistor when the cathode of the diode receives the overcurrent trigger signal sent by the overcurrent detection module.

6. The laser circuit with overcurrent protection circuit according to claim 1, characterized in that, The overcurrent protection execution unit includes: a third field-effect transistor; The third field-effect transistor turns on when it receives a high-level output signal, thus connecting the current loop of the laser diode. When it receives a low-level output signal, it enters an overcurrent protection state, turning off the third field-effect transistor and disconnecting the current loop of the laser diode.

7. The laser circuit with overcurrent protection circuit according to claim 1, characterized in that, The overcurrent detection module includes: a sampling unit; The sampling unit is connected to the laser diode current loop. The sampling unit is used to convert the loop current of the laser diode current loop into a laser diode voltage signal, so as to perform overcurrent detection on the laser diode based on the laser diode voltage signal.

8. The laser circuit having an overcurrent protection circuit according to claim 1, wherein, The overcurrent detection module further includes: a detection unit; The detection unit is connected to the sampling unit and the anti-interference unit respectively. The detection unit is used to receive the laser diode voltage signal sent by the sampling unit and to detect whether the laser diode voltage signal is overcurrent.

9. The laser circuit having an overcurrent protection circuit according to claim 8, characterized by, The detection unit includes: a resistor-capacitor module and a comparator, wherein the input side of the comparator is connected to the resistor-capacitor module and the output side is connected to a diode; The resistor-capacitor module is used to filter the received laser diode voltage signal; The comparator is used to compare the filtered voltage signal with a preset voltage to perform overcurrent detection on the laser diode.

10. An overcurrent protection system for a laser tube, comprising: include: The laser circuit with overcurrent protection circuit according to any one of claims 1-9, and the driving unit and laser diode connected to the laser circuit with overcurrent protection circuit.

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