Laser diode control circuit of laser

Abstract

The utility model discloses a laser diode control circuit of a laser, comprising a pulse control signal generation circuit used for generating grid control pulse signals with adjustable power, frequency and duty ratio; the power amplification circuit is used for amplifying the grid control pulse signal; the grid electrode of the MOS tube is connected with the output end of the power amplification circuit, the source electrode of the MOS tube is connected with one end of a driving resistor, and the other end of the driving resistor is connected with the negative electrode of a driving power supply and a ground wire; the positive electrode of the laser diode is connected with the positive electrode of the driving power supply, the negative electrode is connected with the drain electrode of the MOS tube, and the laser diode is provided with a heat dissipation block; and the temperature acquisition control circuit is used for acquiring temperature data of the heat dissipation block and controlling the on-off state of the driving power supply, and controlling the driving power supply to be adjusted to be in a power-off state under the condition that the temperature data exceeds a preset temperature threshold value. According to the utility model, the heating value can be reduced, the optical power is improved, and the laser diode is protected when the temperature of the laser diode abnormally rises.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of laser, especially relates to a laser diode control circuit of laser. BACKGROUND

[0002] The core of the Digital Micromirror Devices (DMD) used by the laser direct imaging system is a matrix composed of micro-mirrors, each of which can be independently controlled, and the flip angle and speed of the micro-mirror are controlled by the lithography pattern input by the computer, so as to realize high-precision pattern exposure. In the laser direct imaging system, the DMD receives the light emitted by the laser, and after a series of optical component processing, the light beam is projected onto the photosensitive material to form the required pattern. However, the traditional laser direct imaging system has the following disadvantages:

[0003] Firstly, the DMD cannot withstand too much laser power under the irradiation of the laser, and the traditional laser controls the output of continuous light, that is, the laser will always irradiate on the DMD, which will greatly reduce the service life of the DMD.

[0004] Secondly, the traditional laser controls the working mode of the continuous light with fixed power output of the Laser Diode (LD). The characteristic of the LD is that a large amount of heat is generated while emitting light. In this working mode, the LD used by the laser can only work under the rated power condition, because the heat generated by the LD is relatively small, and the general heat dissipation system can easily dissipate the heat to ensure the normal use of the LD. However, if the LD is used in super power mode, the general heat dissipation system is difficult to dissipate the excess heat, resulting in heat accumulation and burning of the LD.

[0005] Thirdly, the output power of the LD in the traditional laser is not adjustable, and the stability is poor.

[0006] Fourthly, the traditional laser is easy to cause damage to the LD due to static electricity or power fluctuation during use. INVENTION CONTENT

[0007] The utility model aims at solving one of the technical problems in the prior art. To this end, the utility model provides a laser diode control circuit of laser, which can reduce the heat generation, improve the optical power, and protect the laser diode when the temperature of the laser diode abnormally rises.

[0008] The laser diode control circuit of laser according to the utility model embodiment comprises:

[0009] The pulse control signal generating circuit is used for generating a gate control pulse signal with adjustable power, frequency and duty cycle.

[0010] a power amplification circuit, an input end of which is connected with an output end of the pulse control signal generation circuit, and the power amplification circuit is used for amplifying the gate control pulse signal;

[0011] a driving circuit, comprising a MOS tube, a driving resistor and a driving power supply, a gate of the MOS tube is connected with an output end of the power amplification circuit, a source is connected with one end of the driving resistor, and the other end of the driving resistor is connected with a negative electrode of the driving power supply and a ground wire respectively;

[0012] a laser diode, a positive electrode of which is connected with a positive electrode of the driving power supply, and a negative electrode is connected with a drain of the MOS tube, and the laser diode is correspondingly provided with a heat dissipation block;

[0013] a temperature acquisition control circuit, used for acquiring temperature data of the heat dissipation block and controlling on-off states of the driving power supply, and in the case that the temperature data exceeds a preset temperature threshold, the driving power supply is controlled to be adjusted to a power-off state.

[0014] The laser diode control circuit of the laser device has at least the following beneficial effects:

[0015] The pulse control signal generation circuit generates the gate control pulse signal with adjustable power, frequency and duty cycle, and then the laser diode is driven after amplification by the power amplification circuit, so that the switching timing of the pulsed light of the laser diode corresponds to the switching timing of the DMD picture. Compared with the traditional laser device using continuous light mode, the laser device uses pulsed light, and the laser does not irradiate on the DMD all the time, which can reduce the heat generation, prolong the service life of the DMD, and improve the optical power. At the same time, the temperature acquisition control circuit can control the driving power supply to be adjusted to a power-off state in the case that the temperature data exceeds a preset temperature threshold, so as to prevent the damage of the laser diode caused by the temperature being too high after the heat dissipation system of the laser device is paralyzed during use.

[0016] According to some embodiments of the present application, the pulse control signal generation circuit comprises:

[0017] a synchronization signal generation module, used for generating a TTL signal with adjustable frequency and duty cycle;

[0018] a laser power control signal generation module, used for generating a laser power control signal with adjustable power;

[0019] a signal integration circuit, used for integrating the TTL signal and the laser power control signal into the gate control pulse signal with adjustable power, frequency and duty cycle, and outputting to an input end of the power amplification circuit.

[0020] According to some embodiments of the utility model, the core piece of the synchronous signal generation module adopts SN75176BDR.

[0021] According to some embodiments of the utility model, the core piece of the signal integration circuit adopts ADG719.

[0022] According to some embodiments of the utility model, the power amplification circuit comprises:

[0023] The first operational amplifier circuit has a first amplification output end and a first amplification input end connected with the output end of the pulse control signal generation circuit, and is used for amplifying the gate control pulse signal by one level to obtain a first voltage;

[0024] The second operational amplifier circuit has a second amplification input end connected with the first amplification output end and a second amplification output end connected with the gate of the MOS tube, and is used for amplifying the first voltage by two levels to obtain a second voltage;

[0025] The negative feedback circuit has a first feedback end connected with the one end of the driving resistor, a second feedback end connected with the other end of the driving resistor and a third feedback end connected between the first amplification output end and the second amplification input end, and is used for adjusting the size of the second voltage according to the voltage difference formed by the driving resistor and the first voltage, so as to linearly regulate the optical power of the laser diode.

[0026] According to some embodiments of the utility model, the first operational amplifier circuit comprises:

[0027] The first resistor has one end connected with the output end of the pulse control signal generation circuit;

[0028] The first amplifier has an inverting input end connected with the other end of the first resistor;

[0029] The second resistor has one end connected with the non-inverting input end of the first amplifier;

[0030] The third resistor has one end connected with the non-inverting input end of the first amplifier and the one end of the second resistor respectively, and the other end is used for connecting the ground wire;

[0031] The first power supply has a positive electrode connected with the other end of the second resistor and a negative electrode connected with the other end of the third resistor and the ground wire respectively;

[0032] The fourth resistor has one end connected with the other end of the first resistor and the inverting input end of the first amplifier respectively, and the other end connected with the output end of the first amplifier.

[0033] The first capacitor is connected in parallel with the fourth resistor.

[0034] According to some embodiments of the present application, the second operational amplifier circuit comprises:

[0035] The fifth resistor has one end connected to the output end of the first amplifier and the other end connected to the third feedback end;

[0036] The second amplifier has its inverting input end connected to the other end of the fifth resistor and the third feedback end respectively;

[0037] The sixth resistor has one end connected to the non-inverting input end of the second amplifier;

[0038] The seventh resistor has one end connected to the non-inverting input end of the second amplifier and the one end of the sixth resistor respectively and the other end connected to the ground wire;

[0039] The second power supply has its positive pole connected to the other end of the sixth resistor and its negative pole connected to the other end of the seventh resistor and the ground wire respectively;

[0040] The eighth resistor has one end connected to the other end of the fifth resistor and the inverting input end of the second amplifier respectively and the other end connected to the output end of the second amplifier;

[0041] The second capacitor is connected in parallel with the eighth resistor.

[0042] According to some embodiments of the present application, the temperature acquisition control circuit comprises:

[0043] The temperature acquisition module is configured to acquire the temperature data of the heat dissipation block;

[0044] The relay has a control end, a first connection end connected to the positive pole of the laser diode, and a second connection end connected to the positive pole of the driving power supply, and is configured to control the on-off state of the driving power supply;

[0045] The control module is connected to the control end and the temperature acquisition module respectively, and is configured to control the relay to be disconnected to adjust the driving power supply to the power-off state when the temperature data exceeds the preset temperature threshold.

[0046] According to some embodiments of the present application, further comprising a protection circuit connected in parallel with the laser diode, the protection circuit is configured to shunt the laser diode in the case of static electricity or large power supply fluctuation.

[0047] According to some embodiments of the utility model, the protection circuit adopts TVS pipe, the positive pole of TVS pipe is connected with the negative pole of laser diode, and the negative pole is connected with the positive pole of laser diode.

[0048] Additional aspects and advantages of the utility model will be partially given in the following description, partially will become obvious from the following description, or be understood by the practice of the utility model. BRIEF DESCRIPTION OF DRAWINGS

[0049] The utility model will be further explained in combination with the drawings and examples, wherein:

[0050] Figure 1 It is the structure diagram of laser diode control circuit of the laser of an embodiment of the utility model;

[0051] Figure 2 It is the contrastive view of existing continuous laser switching time sequence and DMD picture switching time sequence;

[0052] Figure 3 It is the contrastive view of existing pulse laser switching time sequence and DMD picture switching time sequence;

[0053] Figure 4 It is the waveform corresponding view of TTL signal, laser power control signal and gate control pulse signal of an embodiment of the utility model.

[0054] Reference signs:

[0055] FPGA system 111, synchronization signal generation module 112, Stm32 system 120, signal integration circuit 130;

[0056] First operational amplifier circuit 210, second operational amplifier circuit 220, negative feedback circuit 230;

[0057] Heat dissipation block 300;

[0058] Relay 400. DETAILED DESCRIPTION

[0059] The embodiments of the utility model will be described in detail below, the examples of the embodiments are shown in the drawings, wherein the same or similar reference signs represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary, only for explaining the utility model, and can not be understood as the limitation of the utility model.

[0060] In the description of the utility model, need understanding, relate to the direction description, for example the direction or position relation of indication such as upper, lower is based on the direction or position relation shown in drawing, only for the convenience of describing the utility model and simplifying the description, and it is not indicated or implied that the device or element must have a particular orientation, a particular orientation and operation, therefore it cannot be understood as a limitation on the utility model.

[0061] In the description of the utility model, more refers to two or more. If there is a description to the first, the second is only used for distinguishing technical features for the purpose, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features or implicitly indicating the sequence of indicated technical features.

[0062] In the description of the utility model, unless otherwise explicitly limited, the words such as setting, installation, connection should be broadly understood, and the skilled in the art can reasonably determine the specific meaning of the above words in the utility model according to the specific content of the technical scheme.

[0063] The following will be combined Figures 1 to 4 The laser diode control circuit of the laser of the embodiment of the utility model is described clearly and completely, obviously, the following described embodiment is a part of the embodiment of the utility model, not all embodiments.

[0064] Reference Figures 1 to 4 , Figure 1 The structure diagram of the laser diode control circuit of the laser of an embodiment of the utility model, Figure 2 It is the contrastive drawing of the existing continuous laser switching time sequence and DMD picture switching time sequence, Figure 3 It is the contrastive drawing of the existing pulse laser switching time sequence and DMD picture switching time sequence, Figure 4 It is the waveform corresponding drawing of TTL signal, laser power control signal and gate control pulse signal of an embodiment of the utility model.

[0065] The laser diode control circuit of the laser according to the embodiment of the utility model, including pulse control signal generating circuit, power amplifier circuit, drive circuit, laser diode and temperature acquisition control circuit.

[0066] The pulse control signal generating circuit is used to generate the gate control pulse signal with adjustable power, frequency and duty cycle;

[0067] The power amplifier circuit is connected with the output end of the pulse control signal generating circuit, and the power amplifier circuit is used for amplifying the gate control pulse signal;

[0068] The driving circuit comprises a MOS transistor, a driving resistor and a driving power supply, the gate of the MOS transistor is connected with the output end of the power amplification circuit, the source is connected with one end of the driving resistor, and the other end of the driving resistor is connected with the negative pole of the driving power supply and the ground wire respectively.

[0069] The anode of the laser diode is connected with the positive pole of the driving power supply, and the cathode is connected with the drain of the MOS transistor.

[0070] The temperature acquisition control circuit is used for acquiring temperature data of the heat dissipation block 300 and controlling the on-off state of the driving power supply, and the driving power supply is controlled to be adjusted to the power-off state when the temperature data exceeds the preset temperature threshold.

[0071] The pulse control signal generation circuit sets the power of the gate control pulse signal according to the required power value of the laser diode, and sets the frequency and duty cycle of the gate control pulse signal according to the frequency and duty cycle of the DMD picture switching time sequence, so as to realize the synchronization of the switching time sequence of the laser and the switching time sequence of the DMD picture.

[0072] The gate control pulse signal is amplified by the power amplification circuit, so that the input gate control pulse signal can be amplified to the required amplitude, so as to ensure that important information will not be lost in the transmission or processing process, and the quality and reliability of the gate control pulse signal are improved.

[0073] The amplified gate control pulse signal is used to drive the MOS transistor to be turned on, so that the laser diode works normally.

[0074] According to the laser diode control circuit of the laser device, the pulse control signal generation circuit generates the gate control pulse signal with adjustable power, frequency and duty cycle, and then drives the laser diode through the power amplification circuit, so that the switching time sequence of the pulsed light of the laser diode corresponds to the switching time sequence of the DMD picture. Compared with the traditional laser device adopting the continuous light mode, the laser device adopts pulsed light, the laser does not irradiate on the DMD all the time, the heat quantity can be reduced, the service life of the DMD is prolonged, and the optical power can be improved. Meanwhile, the temperature acquisition control circuit can control the driving power supply to be adjusted to the power-off state when the temperature data exceeds the preset temperature threshold, so as to prevent the laser diode from being damaged due to the excessively high temperature after the heat dissipation system of the laser device is paralyzed during use.

[0075] In some embodiments of the utility model, refer to Figure 1 and Figure 4 The pulse control signal generation circuit comprises a synchronization signal generation module, a laser power control signal generation module and a signal integration circuit 130.

[0076] The synchronization signal generation module is used for generating a TTL signal with adjustable frequency and duty cycle.

[0077] The laser power control signal generation module is used for generating a laser power control signal with adjustable power.

[0078] The signal integration circuit 130 is used for integrating the TTL signal and the laser power control signal into a gate control pulse signal with adjustable power, frequency and duty cycle, and outputting the gate control pulse signal to the input end of the power amplification circuit.

[0079] The conventional laser direct imaging system is under the output continuous light mode laser, and the exposure duration is controlled by the DMD picture switching, as shown in the figure, the exposure duration is (t3-t1). Figure 2 If the output continuous light mode laser is directly replaced by the output pulse light mode laser, the DMD picture switching time sequence and the pulse light switching time sequence are not corresponding, as shown in the figure, the exposure duration is (t2-t1), which leads to the exposure duration out of control. Figure 3

[0080] The synchronization signal generation module includes a 485 communication module and a synchronization signal generation module 112.The 485 communication module can be a sub-module of the FPGA system 111, and the FPGA system 111 further includes a DMD control module for controlling the DMD. In some embodiments of the present application, the core chip of the synchronization signal generation module adopts SN75176BDR, the SN75176BDR receives the differential signals A and B sent by the 485 communication module of the FPGA system 111, and converts the differential signals A and B into a synchronization signal (i.e.

[0081] The laser power control signal generation module can be a sub-module of the Stm32 system 120, such as a digital-to-analog conversion module (Digital-to-Analog Converter, DAC).

[0082] As shown in the figure, the laser power control signal generation module receives the digital-to-analog conversion module (DAC) of the Stm32 system 120, and converts the digital-to-analog conversion module (DAC) into a laser power control signal with adjustable power. Figure 4As shown, the level of the laser power control signal is V1, which can be set according to the required power value of the laser diode, the high and low levels of the TTL signal are V2 and 0V respectively, and the frequency and duty cycle of the TTL signal are the same as the DMD picture switching timing. In some embodiments of the present application, the core chip of the signal integration circuit 130 adopts ADG719, ADG719 inputs the laser power control signal and the TTL signal, controls the switching output of a new pulse signal between 0V and V1, that is, the gate control pulse signal, the timing of the gate control pulse signal is the same as the DMD picture switching timing, the DMD picture switching period and the switching period of the laser are both (t4-t1), the frequency is 1 / (t4-t1), the laser opening time is synchronized with the DMD picture switching time as t1, and the closing time of the laser in a single period (t4-t1) is t2, so that the situation that the exposure duration is out of control can be avoided.

[0083] It should be noted that the working principle and process of SN75176BDR and ADG719 are prior art known to those skilled in the art, and will not be described here.

[0084] In some embodiments of the present application, with reference to Figure 1 , the power amplification circuit comprises a first operational amplification circuit 210, a second operational amplification circuit 220 and a negative feedback circuit 230.

[0085] The first operational amplification circuit 210 has a first amplification output end and a first amplification input end connected with the output end of the pulse control signal generation circuit, and the first operational amplification circuit 210 is used for amplifying the gate control pulse signal by one level to obtain a first voltage;

[0086] The second operational amplification circuit 220 has a second amplification input end connected with the first amplification output end and a second amplification output end connected with the gate of the MOS tube, and the second operational amplification circuit 220 is used for amplifying the first voltage by two levels to obtain a second voltage;

[0087] The negative feedback circuit 230 has a first feedback end connected with one end of the driving resistor, a second feedback end connected with the other end of the driving resistor, and a third feedback end connected between the first amplification output end and the second amplification input end, and the negative feedback circuit 230 is used for adjusting the size of the second voltage according to the voltage difference formed between the two ends of the driving resistor and the first voltage, so as to realize the linear regulation of the optical power of the laser diode.

[0088] In some embodiments of the present application, with reference to Figure 1 , the first operational amplification circuit 210 comprises a first resistor, a first amplifier, a second resistor, a third resistor, a first power supply, a fourth resistor and a first capacitor.

[0089] a first resistor, one end of which is connected to an output terminal of the pulse control signal generating circuit;

[0090] a first amplifier, an inverting input terminal of which is connected to the other end of the first resistor;

[0091] a second resistor, one end of which is connected to a non-inverting input terminal of the first amplifier;

[0092] a third resistor, one end of which is connected to the non-inverting input terminal of the first amplifier and the other end of the second resistor respectively, and the other end of which is used for connecting a ground wire;

[0093] a first power supply, a positive electrode of which is connected to the other end of the second resistor, and a negative electrode of which is connected to the other end of the third resistor and the ground wire respectively;

[0094] a fourth resistor, one end of which is connected to the other end of the first resistor and the inverting input terminal of the first amplifier respectively, and the other end of which is connected to an output terminal of the first amplifier;

[0095] a first capacitor, which is connected to the fourth resistor in parallel.

[0096] In some embodiments of the utility model, reference is made to Figure 1 , the second operational amplifier circuit 220 includes a fifth resistor, a second amplifier, a sixth resistor, a seventh resistor, a second power supply, an eighth resistor and a second capacitor.

[0097] the fifth resistor, one end of which is connected to the output terminal of the first amplifier, and the other end of which is connected to the third feedback terminal;

[0098] the second amplifier, an inverting input terminal of which is connected to the other end of the fifth resistor and the third feedback terminal respectively;

[0099] the sixth resistor, one end of which is connected to a non-inverting input terminal of the second amplifier;

[0100] the seventh resistor, one end of which is connected to the non-inverting input terminal of the second amplifier and the other end of the sixth resistor respectively, and the other end of which is used for connecting a ground wire;

[0101] the second power supply, a positive electrode of which is connected to the other end of the sixth resistor, and a negative electrode of which is connected to the other end of the seventh resistor and the ground wire respectively;

[0102] the eighth resistor, one end of which is connected to the other end of the fifth resistor and the inverting input terminal of the second amplifier respectively, and the other end of which is connected to an output terminal of the second amplifier;

[0103] the second capacitor, which is connected to the eighth resistor in parallel.

[0104] In some embodiments of the utility model, first operational amplifier circuit 210 carries out one stage amplification to gate control pulse signal and obtains first voltage VO1, second operational amplifier circuit 220 carries out two stage amplification to first voltage VO1 and obtains second voltage VO2, the core piece of negative feedback circuit 230 adopts MAX4173FEUT_T, MAX4173FEUT_T detects the voltage difference of sampling resistance and carries out proportional amplification and exports a negative feedback voltage VO (sampling resistance and driving resistance are connected in parallel), VO adds VO1 and adjusts the value of VO2, changes the conduction current of MOS tube, realizes the output pulse laser of linear regulation laser diode, makes the whole closed loop feedback system be in dynamic balance, to reach the purpose of stable output pulse laser.

[0105] It should be noted that the specific working principle of the first operational amplifier circuit 210 and the second operational amplifier circuit 220 is the prior art known to those skilled in the art, which will not be described here.

[0106] In some embodiments of the utility model, reference Figure 1 The temperature acquisition control circuit includes a temperature acquisition module, a relay 400 and a control module.

[0107] The temperature acquisition module is configured to acquire temperature data of the heat dissipation block 300.

[0108] The relay 400 has a control end, a first connection end connected to the positive electrode of the laser diode, and a second connection end connected to the positive electrode of the driving power supply. The relay 400 is configured to control the on-off state of the driving power supply.

[0109] The control module is connected to the control end and the temperature acquisition module, respectively. The control module is configured to control the relay 400 to be disconnected when the temperature data exceeds a preset temperature threshold, so as to adjust the driving power supply to a power-off state.

[0110] The temperature acquisition module and the control module can be integrated in the Stm32 system 120. The control module receives the temperature data uploaded by the temperature acquisition module. If the temperature data exceeds the preset temperature threshold, the relay 400 is controlled to be disconnected, so as to adjust the driving power supply to a power-off state, thereby preventing the damage of the laser diode caused by the high temperature after the heat dissipation system is paralyzed during use.

[0111] In some embodiments of the utility model, reference Figure 1 Further comprising a protection circuit connected in parallel with the laser diode. The protection circuit is configured to shunt the laser diode in the case of static electricity or large power supply fluctuation. The protection circuit can use a common diode. The positive electrode of the common diode is connected to the negative electrode of the laser diode, and the negative electrode is connected to the positive electrode of the laser diode, thereby preventing reverse overvoltage.

[0112] In some embodiments of the utility model, reference Figure 1 The protection circuit adopts a TVS tube, the positive electrode of the TVS tube is connected with the negative electrode of the laser diode, and the negative electrode is connected with the positive electrode of the laser diode. The TVS tube is a special diode, and its working principle is based on the breakdown effect of PN junction. When the voltage in the circuit exceeds the normal working voltage, the TVS tube will automatically conduct, and the overvoltage will be drained to the ground or other places, so as to protect the laser diode, suppress the transient overvoltage, and protect the laser diode from the influence of transient events such as power fluctuation, electromagnetic interference, lightning strike, etc. The response speed of the TVS tube is very fast, and it can quickly react within nanoseconds, so the protection circuit has very good effect, and can automatically restore normal working state after the overvoltage disappears, without any influence on the circuit. In addition, the Zener breakdown current of the TVS tube is small, and the voltage stabilizing current of more than 10V is only 1mA. The voltage characteristic of the TVS tube is usually nonlinear, the resistance is high before breakdown, and the current increases rapidly after breakdown, and the voltage remains at the clamping voltage value. The TVS tube can automatically restore normal working state after the overvoltage disappears, so it can be reused.

[0113] It should be noted that the protection circuit can also adopt other circuit structures that can protect the laser diode in the case of static electricity or large power fluctuation, and cannot be regarded as a limitation of the utility model.

[0114] The above describes the embodiments of the utility model in detail in combination with the drawings, but the utility model is not limited to the above embodiments, and various changes can be made within the knowledge range possessed by those skilled in the art without departing from the purpose of the utility model.

Claims

1. A laser diode control circuit for a laser, characterized by include: A pulse control signal generation circuit is used to generate gate control pulse signals whose power, frequency, and duty cycle are all adjustable. A power amplifier circuit, the input of which is connected to the output of the pulse control signal generation circuit, is used to amplify the gate control pulse signal; The driving circuit includes a MOSFET, a driving resistor, and a driving power supply. The gate of the MOSFET is connected to the output terminal of the power amplifier circuit, and the source is connected to one end of the driving resistor. The other end of the driving resistor is connected to the negative terminal of the driving power supply and the ground line, respectively. A laser diode, the positive terminal of which is connected to the positive terminal of the driving power supply, and the negative terminal of which is connected to the drain of the MOS transistor, and a heat sink is provided for the laser diode accordingly; A temperature acquisition and control circuit is used to acquire temperature data of the heat sink and control the on / off state of the drive power supply, and control the drive power supply to be turned off when the temperature data exceeds a preset temperature threshold.

2. The laser diode control circuit for a laser according to claim 1, characterized by, The pulse control signal generation circuit includes: Synchronization signal generation module, used to generate TTL signals with adjustable frequency and duty cycle; A laser power control signal generation module is used to generate adjustable laser power control signals. A signal integration circuit is used to integrate the TTL signal and the laser power control signal into a gate control pulse signal whose power, frequency, and duty cycle are all adjustable, and output it to the input terminal of the power amplifier circuit.

3. The laser diode control circuit for a laser according to claim 2, wherein The core chip of the synchronization signal generation module is SN75176BDR.

4. The laser diode control circuit for a laser according to claim 2, wherein The core chip of the signal integration circuit is ADG719.

5. The laser diode control circuit for a laser according to claim 1, wherein, The power amplifier circuit includes: The first operational amplifier circuit has a first amplified output terminal and a first amplified input terminal connected to the output terminal of the pulse control signal generation circuit. The first operational amplifier circuit is used to amplify the gate control pulse signal in one stage to obtain a first voltage. The second operational amplifier circuit has a second amplification input terminal connected to the first amplification output terminal and a second amplification output terminal connected to the gate of the MOS transistor. The second operational amplifier circuit is used to amplify the first voltage in two stages to obtain a second voltage. The negative feedback circuit has a first feedback terminal connected to one end of the driving resistor, a second feedback terminal connected to the other end of the driving resistor, and a third feedback terminal connected between the first amplified output terminal and the second amplified input terminal. The negative feedback circuit is used to adjust the magnitude of the second voltage according to the voltage difference formed across the driving resistor and the first voltage, so as to achieve linear adjustment of the optical power of the laser diode.

6. The laser diode control circuit for a laser according to claim 5, wherein, The first operational amplifier circuit includes: The first resistor has one end connected to the output terminal of the pulse control signal generation circuit. The first amplifier has its inverting input terminal connected to the other end of the first resistor; The second resistor has one end connected to the non-inverting input terminal of the first amplifier; The third resistor has one end connected to the non-inverting input terminal of the first amplifier and one end of the second resistor, and the other end is used to connect to the ground wire. A first power supply has a positive terminal connected to the other end of the second resistor and a negative terminal connected to the other end of the seventh resistor and the ground wire; A fourth resistor has one end connected to the other end of the first resistor and the inverting input terminal of the first amplifier and the other end connected to the output terminal of the first amplifier; A first capacitor is connected in parallel with the fourth resistor.

7. The laser diode control circuit for a laser according to claim 6, wherein The second operational amplifier circuit comprises: A fifth resistor has one end connected to the output terminal of the first amplifier and the other end connected to the third feedback terminal; A second amplifier has an inverting input terminal connected to the other end of the fifth resistor and the third feedback terminal; A sixth resistor has one end connected to the non-inverting input terminal of the second amplifier; A seventh resistor has one end connected to the non-inverting input terminal of the second amplifier and the other end connected to the ground wire; A second power supply has a positive terminal connected to the other end of the sixth resistor and a negative terminal connected to the other end of the seventh resistor and the ground wire; An eighth resistor has one end connected to the other end of the fifth resistor and the inverting input terminal of the second amplifier and the other end connected to the output terminal of the second amplifier; A second capacitor is connected in parallel with the eighth resistor.

8. The laser diode control circuit for a laser according to claim 1, wherein, The temperature acquisition control circuit comprises: A temperature acquisition module configured to acquire the temperature data of the heat dissipation block; A relay having a control terminal, a first connection terminal connected to the positive terminal of the laser diode, and a second connection terminal connected to the positive terminal of the driving power supply, the relay being configured to control the on-off state of the driving power supply; A control module connected to the control terminal and the temperature acquisition module, the control module being configured to control the relay to be disconnected to adjust the driving power supply to be in a power-off state when the temperature data exceeds a preset temperature threshold.

9. The laser diode control circuit for a laser according to claim 1, wherein, The protection circuit comprises a TVS tube connected in parallel with the laser diode, the TVS tube being configured to shunt the laser diode when static electricity or large power supply fluctuation occurs.

10. The laser diode control circuit for a laser according to claim 9, wherein, The protection circuit comprises a TVS tube connected in parallel with the laser diode, the TVS tube being configured to shunt the laser diode when static electricity or large power supply fluctuation occurs.

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