Temperature control device for non-magnetic packaging VCSEL laser

Abstract

A temperature control device for a non-magnetic packaging VCSEL laser comprises a main control module which adopts NI equipment and a LabVIEW program, provides high-resolution data acquisition and real-time PID parameter adjustment, and realizes accurate temperature control. And the high-frequency modulation module shifts the temperature control signal to a high frequency band to suppress low-frequency magnetic field noise. The power supply module is composed of a switching power supply and a voltage stabilizing circuit, provides a stable power supply for the power amplifier operational amplifier and the radiator, and reduces noise and transient interference. The power amplification module is composed of two stages of amplification circuits, and a low-noise amplifier and a high-frequency current feedback amplifier are adopted to achieve efficient power amplification of signals. The heating module comprises a double-layer 2N polar distance heating film and an NTC negative feedback thermistor, the upper magnetic field and the lower magnetic field of a heating coil are mutually offset, non-magnetic heating is ensured, meanwhile, the NTC thermistor is combined for accurate temperature measurement, current is controlled in cooperation with a PID algorithm, and temperature stability is ensured. Compared with the prior art, the device has remarkable advantages in the aspects of non-magnetic heating, low-noise power supply and temperature control precision.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor laser control, in particular to a temperature control device for a magnetless packaged VCSEL laser. Through temperature closed-loop control, it is beneficial to achieve high-precision temperature regulation of the VCSEL laser, significantly reduce magnetic field noise interference, and is applicable to application scenarios with extremely high requirements for temperature and magnetic field stability such as atomic magnetic measurement and optical communication. Background Art

[0002] VCSEL (Vertical-Cavity Surface-Emitting Laser) has become an important light source device in the fields of atomic magnetic measurement, optical communication, atomic clock, lidar, optical storage, etc. due to its advantages such as small size, high efficiency, and easy integration. In these applications, as the core light source, the performance of the VCSEL laser directly determines the overall performance index of the system. Especially in high-precision measurement systems, the requirements for its stability and reliability are particularly strict.

[0003] The frequency and wavelength of the VCSEL laser are extremely sensitive to temperature changes. Fluctuations in the ambient temperature will cause significant changes in its output characteristics, thereby affecting the accuracy and stability of the system. In order to meet the performance requirements of high-precision systems, it is necessary to maintain the stable operation of the VCSEL laser through precise temperature control.

[0004] Traditional electric heating methods generate Joule heat by driving a heater with current to regulate the temperature. However, according to the Biot-Savart law, a magnetic field is inevitably generated during the heating process by the current. This magnetic field interference will have an adverse impact on applications that require near-zero magnetic field or extremely low magnetic field noise. In addition, the materials used in many heating devices are magnetic, further increasing the complexity of magnetic field noise, making it difficult for traditional heating methods to meet the requirements of these specific scenarios.

[0005] Therefore, in zero magnetic field or micro magnetic field application scenarios, magnetless heating technology has become a key solution. This technology needs to maintain the temperature stability of the VCSEL laser while minimizing the magnetic field noise generated during the heating process to meet the stringent requirements of specific scenarios for magnetic field and temperature stability. In order to achieve efficient, stable magnetless heating and achieve temperature controllability, it is necessary to design a temperature control device to ensure the stable operation of the magnetless packaged VCSEL laser with low magnetic noise. Summary of the Invention

[0006] In view of the defects or deficiencies of the prior art, the present invention provides a temperature control device for a magnetless packaged VCSEL laser. Through temperature closed-loop control, it is beneficial to achieve high-precision temperature regulation of the VCSEL laser, significantly reduce magnetic field noise interference, and is applicable to application scenarios with extremely high requirements for temperature and magnetic field stability, such as atomic magnetic measurement and optical communication.

[0007] The technical solution of the present invention is as follows:

[0008] A temperature control device for a magnetless packaged VCSEL laser, characterized in that it includes a first layer 2 of pole pitch heating films distributed on the upper surface of an aluminum nitride ceramic packaging substrate, where N is a positive integer, and a second layer 2 of pole pitch heating films distributed on the lower surface of the aluminum nitride ceramic packaging substrate and connected in series with the first layer 2 of pole pitch heating films. At the center of the first layer 2 of pole pitch heating films, there are a VCSEL laser and an NTC negative feedback thermistor. The second layer 2 of pole pitch heating films is sequentially connected to the output end of a multiplier through a second-stage power amplifier circuit and a first-stage voltage amplifier circuit. The first input end of the multiplier is connected to the PID temperature control signal output end of the main control module, the second input end of the multiplier is connected to the sine modulation signal output end of a function generator, and the NTC negative feedback thermistor is connected to the PID temperature feedback signal input end of the main control module. N pole pitch heating films, N is a positive integer, and a second layer 2 of pole pitch heating films distributed on the lower surface of the aluminum nitride ceramic packaging substrate and connected in series with the first layer 2 of pole pitch heating films. N pole pitch heating films N At the center of the first layer 2 of pole pitch heating films, there are a VCSEL laser and an NTC negative feedback thermistor. The second layer 2 of pole pitch heating films is sequentially connected to the output end of a multiplier through a second-stage power amplifier circuit and a first-stage voltage amplifier circuit. The first input end of the multiplier is connected to the PID temperature control signal output end of the main control module, the second input end of the multiplier is connected to the sine modulation signal output end of a function generator, and the NTC negative feedback thermistor is connected to the PID temperature feedback signal input end of the main control module. N pole pitch heating films N pole pitch heating films are sequentially connected to the output end of a multiplier through a second-stage power amplifier circuit and a first-stage voltage amplifier circuit. The first input end of the multiplier is connected to the PID temperature control signal output end of the main control module, the second input end of the multiplier is connected to the sine modulation signal output end of a function generator, and the NTC negative feedback thermistor is connected to the PID temperature feedback signal input end of the main control module.

[0009] The second-stage power amplifier circuit is equipped with an air-cooled radiator. The second-stage power amplifier circuit outputs a high-frequency sine temperature control signal to the double-layer 2 N pole pitch heating films. The air-cooled radiator is connected to the output end of a switching power supply through a voltage stabilizing circuit. The output end of the switching power supply is respectively connected to the second-stage power amplifier circuit and the first-stage voltage amplifier circuit. The input end of the switching power supply is connected to 220V alternating current, and the output voltage of the output end of the switching power supply is ±15V.

[0010] The main control module includes an upper computer panel and an NIDAQ data acquisition processor. The NIDAQ data acquisition processor includes a data acquisition card and its upper computer program. The data acquisition card is used to collect temperature signals. The upper computer program is used to monitor the real-time temperature curve, desired temperature setting, and PID parameter setting adjustment. The upper computer program is built on the LabVIEW development environment.

[0011] The PID temperature control signal output by the main control module has the following expression:

[0012]

[0013] where u(t) is the PID temperature control signal, t represents time, e is the difference between the temperature set value and the temperature measured value, and K c is the proportionality coefficient, T i is the integral time constant, and T d is the derivative time constant.

[0014] The NTC negative feedback thermistor includes the following relationship:

[0015]

[0016] where T represents temperature, and R T is the resistance value at temperature T, T 0 is the reference temperature, and R 0 is the resistance value at the reference temperature T 0 and B is the material constant, and e is the natural constant.

[0017] The second-stage power amplifier circuit includes an LT1210CR operational amplifier.

[0018] The first-stage voltage amplifier circuit includes an OP27GS operational amplifier.

[0019] The voltage regulator circuit includes an LM2596T switching voltage regulator.

[0020] The advantages of the present invention compared with the prior art are as follows:

[0021] (1) The present invention uses NIDAQ to collect and process data in real time, provides high-resolution analog-to-digital conversion, ensures accurate signal acquisition, is more suitable for high-precision applications, is modular and highly scalable, and can facilitate multi-channel acquisition and function upgrade according to requirements and the environment.

[0022] (2) The present invention moves the heating drive signal to the high-frequency band through high-frequency modulation, avoids the interference of low-frequency magnetic field noise on the measurement bandwidth, and ensures the stability and accuracy of the precision measurement system.

[0023] (3) The present invention powers the two-stage power amplifier circuit and the adapted air-cooled radiator through a customized voltage regulator circuit, reduces noise and transient interference, and ensures the stable operation of the power amplifier board.

[0024] (4) The present invention uses a double-layer 2 N pole pitch heating coil, the current distribution is more uniform, the heat distribution is more balanced, reduces local overheating or overcooling problems, adopts a double-layer opposed structure, the magnetic fields generated by the upper and lower layers cancel each other out, almost completely eliminates the magnetic field interference during the heating process, and electroplated copper has excellent antioxidant and corrosion resistance properties, increasing long-term stability and durability. Description of the Drawings

[0025] Figure 1It is a schematic structural diagram of a temperature control device for a non-magnetic packaged VCSEL laser to implement the present invention. Figure 1 In it, 1 is the host computer panel, 2 is the sine modulation signal, 3 is the modulator or multiplier, and 4 is the high-frequency sine temperature control signal. Figure 1 It includes a main control module, a high-frequency modulation module, a power amplifier module, and a heating module connected in sequence. The power amplifier module is connected to the power supply module, and the high-frequency modulation module is connected to the function generator. The main control module includes a host computer panel and a data acquisition processor (NIDAQ, National Instruments Data Acquisition). The high-frequency modulation module includes a modulator, and the modulator receives the sine modulation signal from the function generator and the temperature control signal output from the data acquisition processor respectively. The power amplifier module includes an air-cooled radiator, a first-stage voltage amplification circuit and a second-stage power amplification circuit connected in sequence. The first-stage voltage amplification circuit is connected to the output end of the modulator. The heating module includes a double-layer 2 N pole-distance heating film (N is a positive integer), a VCSEL laser (Vertical-Cavity Surface-Emitting Laser), and an NTC negative feedback thermistor (NTC-Negative Temperature Coefficient thermistor). The double-layer 2 N pole-distance heating film receives the high-frequency sine temperature control signal output from the second-stage power amplification circuit. The NTC negative feedback thermistor transmits the feedback signal to the data acquisition processor, and the data acquisition processor outputs the temperature control signal in the PID mode (PID, Proportion Integral Derivative). The power supply module includes a switching power supply and a voltage stabilizing power supply. The switching power supply is connected to 220V alternating current and outputs ±15V to supply power to the first-stage voltage amplification circuit, the second-stage power amplification circuit, and the voltage stabilizing circuit respectively. The voltage stabilizing circuit is connected to the air-cooled radiator.

[0026] Figure 2 is Figure 1 the 2 N schematic structural diagram of the pole-distance heating film in the heating module. Figure 2 In it, it is a single-layer 2 3 pole-distance heating film, that is, an 8-pole-distance heating film.

[0027] Figure 3 is Figure 1 the circuit diagram of the first-stage voltage amplification of the power amplifier module in it. Figure 3The middle circuit belongs to a non-inverting amplifier circuit with an amplification factor of 1 + R6 / R4 = 3. P2 is a BNC (Bayonet Nut Connector) port. VIN1 is a feedback network label indicating the connection of two circuits. The +15 and -15 network labels indicate connections to +15V and -15V voltages respectively (-15V is the reverse input). U2 is the second chip or the OP27GS operational amplifier, and OP27GS is the model number. The OP27GS operational amplifier has 8 pins. Pin 1 is the first BAL balance terminal, Pin 2 is the IN- inverting input terminal, Pin 3 is the IN+ non-inverting input terminal, Pin 4 is the V- power supply negative terminal (-15V), Pin 5 is the NC no-connection terminal, Pin 6 is the OUT output terminal (for connecting to the VIN1 input voltage source), Pin 7 is the V+ power supply positive terminal (+15V), and Pin 8 is the second BAL balance terminal. R4 to R7 are the 4th to 7th resistors, C5 to C10 are the 5th to 10th capacitors, P2 is a standard BNC interface (BNC, Bayonet Nut Connector), and GND is the ground terminal.

[0028] Figure 4 is Figure 1 The circuit diagram of the second-stage power amplification in the power amplifier module in Figure 4 The middle circuit belongs to a non-inverting amplifier circuit with an amplification factor of 1 + R3 / R1 = 21. P1 is a BNC port. The VIN1 network label indicates the connection point with Figure 3 the first-stage voltage amplification circuit in

[0029] Figure 5 is Figure 1 The circuit diagram of the voltage regulation in the voltage module in Figure 5It includes an input of +15V voltage and an output of +12V voltage. U4 is the fourth chip or the LM2596T switching regulator, and LM2596T is the model number. The LM2596T switching regulator includes 5 pins. The first pin is the VIN input voltage terminal, the second pin is the OUTPUT output voltage terminal, the third pin is the GND ground terminal, the fourth pin is the FB feedback terminal, and the fifth pin is the ON# / OFF switch terminal. L1 is the first inductor, D1 is the voltage regulator diode, and C11 to C14 are the 11th capacitor to the 14th capacitor.

[0030] The reference numerals are explained as follows: 1 - NIDAQ (its input terminal is connected to the NTC negative feedback thermistor, and it outputs a temperature control signal); 2 - sine modulation signal; 3 - multiplier (modulating the temperature control signal to high frequency) or modulator; 4 - high-frequency sine temperature control signal (input to the double-layer 2 N pole pitch heating film). Detailed implementation manners

[0031] The following combines the accompanying drawings ( Figures 1 - 5 ) and embodiments to describe the present invention.

[0032] Figure 1 is a schematic structural diagram of a temperature control device for a non-magnetic packaged VCSEL laser to implement the present invention. Figure 2 is Figure 1 a schematic structural diagram of the 2 N pole pitch heating film of the heating module in. Figure 3 is Figure 1 the first-stage voltage amplification circuit diagram of the power amplifier module in. Figure 4 is Figure 1 the second-stage power amplification circuit diagram of the power amplifier module in. Figure 5 is Figure 1 the voltage stabilization circuit diagram of the voltage module in. Refer to Figures 1 to 5 As shown, a temperature control device for a non-magnetic packaged VCSEL laser includes a first-layer 2 N pole pitch heating film distributed on the upper surface of the aluminum nitride ceramic packaging substrate, N is a positive integer, and a second-layer 2 N pole pitch heating film distributed on the lower surface of the aluminum nitride ceramic packaging substrate and connected in series with the first-layer 2 N pole pitch heating film. At the center of the first-layer 2 N pole pitch heating film, a VCSEL laser and an NTC negative feedback thermistor are provided. The second-layer 2 NThe pole pitch heating film is connected to the output terminal of the multiplier 3 through the second-stage power amplifier circuit and the first-stage voltage amplifier circuit in sequence. The first input terminal of the multiplier 3 is connected to the PID temperature control signal output terminal of the main control module. The second input terminal of the multiplier 3 is connected to the output terminal of the sine modulation signal 2 of the function generator. The NTC negative feedback thermistor is connected to the PID temperature feedback signal input terminal of the main control module.

[0033] The second-stage power amplifier circuit is equipped with an air-cooled radiator. The second-stage power amplifier circuit outputs a high-frequency sine temperature control signal 4 to the double-layer 2 N pole pitch heating film. The air-cooled radiator is connected to the output terminal of the switching power supply through a voltage stabilizing circuit. The output terminal of the switching power supply is respectively connected to the second-stage power amplifier circuit and the first-stage voltage amplifier circuit. The input terminal of the switching power supply is connected to 220V alternating current. The output voltage of the output terminal of the switching power supply is ±15V. The main control module includes an upper computer panel 1 and an NIDAQ data acquisition processor. The NIDAQ data acquisition processor includes a data acquisition card and its upper computer program. The data acquisition card is used to collect temperature signals. The upper computer program is used to monitor the real-time temperature curve, desired temperature setting, and PID parameter setting adjustment. The upper computer program is built on the LabVIEW development environment.

[0034] The PID temperature control signal output by the main control module has the following expression:

[0035]

[0036] where u(t) is the PID temperature control signal, t represents time, e is the difference between the temperature set value and the temperature measured value, K c is the proportionality coefficient, T i is the integral time constant, T d is the differential time constant.

[0037] The NTC negative feedback thermistor includes the following relationship:

[0038]

[0039] where T represents temperature, R T is the resistance value at temperature T, T 0 is the reference temperature, R 0 is the resistance value at the reference temperature T 0 when, B is the material constant, and e is the natural constant.

[0040] The second-stage power amplifier circuit includes an LT1210CR operational amplifier. The first-stage voltage amplifier circuit includes an OP27GS operational amplifier. The voltage stabilizing circuit includes an LM2596T switching voltage regulator.

[0041] The present invention discloses a temperature control device for a magnetically shielded VCSEL laser, belonging to the technical field of semiconductor laser control. Through temperature closed-loop control, the device realizes high-precision temperature regulation of the VCSEL laser and significantly reduces magnetic field noise interference. The device includes a main control module, a high-frequency modulation module, a power supply module, a power amplifier module, and a heating module. The main control module uses NI equipment and LabVIEW programs to provide high-resolution data acquisition and real-time PID parameter adjustment to achieve precise temperature control. The high-frequency modulation module shifts the temperature control signal to a high-frequency band to suppress low-frequency magnetic field noise. The power supply module consists of a switching power supply and a voltage stabilizing circuit to provide stable power for the power amplifier operational amplifier and the radiator, reducing noise and transient interference. The power amplifier module consists of two-stage amplification circuits, using a low-noise amplifier and a high-frequency current feedback amplifier to achieve efficient power amplification of the signal. The heating module includes a double-layer 2 N pole-pitch heating film and an NTC negative feedback thermistor. The magnetic fields of the upper and lower layers of the heating coil cancel each other out to ensure magnetically shielded heating. At the same time, the NTC thermistor is combined to accurately measure the temperature, and the current is controlled in cooperation with the PID algorithm to ensure temperature stability. Compared with traditional technologies, this device has significant advantages in magnetically shielded heating, low-noise power supply, and temperature control accuracy, and is suitable for application scenarios with extremely high requirements for temperature and magnetic field stability, such as atomic magnetic measurement and optical communication.

[0042] A temperature control device for a magnetically shielded VCSEL laser includes a main control module, a high-frequency modulation module, a power supply module, a power amplifier module, and a heating module. The main control module realizes temperature setting, PID parameter adjustment, and real-time temperature monitoring through a host computer program. The data acquisition card collects temperature signals and outputs temperature control signals. The high-frequency modulation module multiplies the temperature control signal by a sine wave through a multiplier, and then uses a power amplifier to amplify the power of the modulated control signal to drive heating. The power supply module includes a switching power supply and a voltage stabilizing circuit to provide a smooth and stable DC voltage for the power amplifier module, reducing transient interference and high-frequency noise. The power amplifier module consists of a first-stage voltage amplification circuit, a second-stage power amplification circuit, and an air-cooled radiator to perform power amplification to drive the heating module. The heating module includes a double-layer 2N pole-pitch heating film and an NTC negative feedback thermistor. The heating film generates Joule heat using the driving current to achieve heating. The thermistor detects the temperature in real time and feeds it back to the main control module to achieve closed-loop temperature control.

[0043] The main control module adjusts the temperature through the PID temperature control algorithm. By adjusting the control variable, the actual output is made as close as possible to the set value. The basic algorithm of PID is as follows:

[0044]

[0045] where t represents time, u(t) is the control signal, e is the difference between the temperature set value and the temperature measured value, and K c is the proportionality coefficient, and T i is the integral time constant, and T d is the differential time constant.

[0046] The high-frequency modulation module multiplies the temperature control signal by the sine oscillation signal using a multiplier, so that the heating drive signal is modulated to the high-frequency band to suppress the low-frequency magnetic field noise.

[0047] The switching power supply of the power supply module converts 220V AC into ±15V to provide stable electrical energy for the two-stage operational amplifier. The voltage stabilizing circuit inputs +15V to provide a stable 12V voltage to provide stable electrical energy for the air-cooled radiator.

[0048] The first-stage voltage amplification circuit of the power amplifier module uses a low-noise precision operational amplifier, and the second-stage power amplification circuit uses a high-frequency current feedback amplifier to achieve high-efficiency power amplification of small signals, and the temperature of the second-stage operational amplifier is reduced by an air-cooled radiator.

[0049] The double-layer 2 N pole pitch heating film material is selected as electroplated copper, with a size of 6.2mm * 6.2mm, distributed on both sides of the AIN substrate. Through symmetrical design, the upper and lower heating films are connected in series, and the magnetic fields generated by the currents cancel each other out to reduce the magnetic field noise.

[0050] The present invention provides a temperature control device for a magnetless packaged VCSEL laser in view of the defects or deficiencies of the prior art, and realizes temperature closed-loop control through a host computer program. This device can provide a highly stable working temperature and low magnetic field noise to solve the problems raised in the background technology.

[0051] A temperature control device for a non-magnetic encapsulated VCSEL laser: It includes five parts: a main control module, a high-frequency modulation module, a power supply module, a power amplifier module, and a heating module; the main control module is used for the control of the temperature control device, mainly including NIDAQ (National Instruments Data Acquisition), which is a series of hardware and software tools developed by National Instruments for collecting analog signals, digital signals, and other forms of data. A dedicated host computer program is used to set the temperature and PID (Proportion Integral Derivative) parameters. The NI board card completes data acquisition and outputs temperature control signals to achieve automatic temperature control; the high-frequency modulation module uses a multiplier to multiply the temperature control signal by a sine wave to modulate the heating drive voltage to a higher frequency, so that the original low-frequency noise is far from the measurement bandwidth of the system; the power supply module is used to regulate the voltage and provide a smooth voltage supply for the power amplifier module to reduce the influence of high-frequency noise or transient interference in the power supply on the device; the power amplifier module amplifies the input heating drive voltage to a level sufficient to drive the VCSEL laser without changing the characteristics of the signal; the heating module performs non-magnetic heating on the VCSEL laser and detects the temperature in real time.

[0052] The main control module described above includes an NI device, a data acquisition card, and a host computer program. The NI device is used to connect the data acquisition card and support the host computer program. The data acquisition card is used to collect the temperature signal. The host computer program is used to monitor the real-time temperature curve, set the desired temperature, and adjust the PID parameter settings. The host computer program is built in the LabVIEW (Laboratory Virtual Instrument Engineering Workbench) development environment.

[0053] The high-frequency modulation module described above modulates the drive current of the electric heating to a high-frequency band. Since the bandwidth of the precision measurement system is usually small and the response is in the low-frequency band, the high-frequency modulation effectively suppresses the low-frequency magnetic field noise generated by the electric heating.

[0054] The power supply module described above includes a switching power supply and a voltage stabilizing circuit. The switching power supply is a power supply device that converts the input 220V AC voltage into the electrical energy required by the voltage stabilizing circuit and the power amplifier module. The voltage stabilizing circuit is a circuit that provides a stable output voltage for the air-cooled radiator in the power amplifier module.

[0055] The power amplifier module consists of a first-stage voltage amplification circuit, a second-stage power amplification circuit, and an air-cooled radiator. The first-stage voltage amplification circuit is composed of a low-noise, precision operational amplifier to form a voltage amplification circuit, providing excellent low-noise and high-precision amplification performance and having good load driving ability. The second-stage power amplification circuit uses a high-frequency current feedback amplifier to form a power amplification circuit, which has a high output current and excellent large-signal characteristics, and efficiently amplifies the input high-frequency sinusoidal voltage signal to effectively drive the heating module. The air-cooled radiator is a heat dissipation device that uses air convection to reduce the temperature of the second-stage power amplification circuit chip. When the power amplifier is working, heat is generated because energy is lost when current passes through electronic components, and this energy is converted into heat, causing the temperature of the second-stage power amplification circuit to rise, resulting in performance degradation and shortened lifespan. By forcing air to flow through the fan, the heat is taken away from heat-conducting components such as the heat sink to achieve efficient heat dissipation of the device.

[0056] The heating module includes an NTC (Negative Temperature Coefficient) negative feedback thermistor and a double-layer N pole pitch heating film. The double-layer N pole pitch heating film adopts a double-layer pasted-together method, N pole pitch coil configuration. The material is selected as electroplated copper, with a size of 6.2mm * 6.2mm. The upper and lower non-magnetic heating films are connected in series, and the magnetic fields generated by the current cancel each other out, further reducing the magnetic field generated by the heating film. The NTC negative feedback thermistor is a component whose resistance decreases as the temperature increases. The resistance value changes non-linearly with temperature and can be approximately described by the Steinhart-Hart equation:

[0057]

[0058] where T represents temperature, T 0 is the reference temperature, R T is the resistance value at temperature T, R 0 is the resistance value at the reference temperature T 0 and B is the material constant, which depends on the material characteristics of the thermistor.

[0059] Such as Figure 1Shown as follows: The present invention is a temperature control device for a magnetless packaged VCSEL laser, which includes five parts: a main control module, a high-frequency modulation module, a power supply module, a power amplifier module, and a heating module. The main control module is provided with a host computer panel (1), which is convenient for observing the temperature curve, setting and adjusting the PID parameters and the desired temperature. The output temperature control signal is modulated (3) by a sine signal (2), which can effectively reduce the low-frequency magnetic field noise. The power amplifier module includes a first-stage voltage amplification circuit, a second-stage power amplification circuit, and an air-cooled radiator, which generates a high-frequency sine temperature control signal (4). To ensure the stability of the power amplifier module, a switching power supply and a voltage stabilizing circuit in the power supply module provide stable power for the two-stage amplifier and the air-cooled radiator. The heating module is composed of a double-layer 2 N pole pitch heating film and an NTC negative feedback thermistor.

[0060] As Figure 2 shown: The material of the double-layer 2 N pole pitch heating film is selected as electroplated copper, and a 2 3 pole pitch heating film with a size of 6.2mm * 6.2mm is distributed on both sides of the AIN (aluminum nitride ceramic packaging substrate) substrate. The upper and lower heating films are connected in series, and the magnetic fields generated by the currents in the two adjacent heating films cancel each other out. The design ensures the symmetry of the coil distribution and avoids local overheating. The temperature of the heating film is detected in real time by combining the NTC thermistor, and the current is adjusted in cooperation with the PID controller to achieve precise control of the heating temperature.

[0061] As Figure 3 shown: The first-stage voltage amplification circuit uses an OP27GS operational amplifier. Pins 1 and 8 are BAL pins, which are used to adjust the balance of the input terminal to reduce the influence of the input bias current. Pins 2 and 3 are IN- and IN+, which are the inverting and non-inverting input terminals respectively. Pins 4 and 7 are V- and V+, which are the negative and positive poles of the power supply terminal respectively. In the present invention, they are connected to -15V and +15V respectively. Pin 5 is an NC non-connection terminal, which has no internal connection. Pin 6 is OUT, the output terminal of the operational amplifier signal. The input path is the P2-end standard BNC interface. This circuit is an inverting amplifier, and multiple capacitors are used for broadband filtering to reduce the interference of the external power supply to the circuit. Its main function is to accurately process and amplify low-frequency small signals.

[0062] As Figure 4As shown: The second-stage power amplifier circuit uses an LT1210 operational amplifier to drive the load, has a high power output capacity, and is equipped with feedback control and power supply filtering design. Pins 1 and 2 are -IN and +IN, which are the inverting input terminal and the non-inverting input terminal respectively. Pin 3 is SHUTDOWN, which is used to turn off or enable the amplifier output. Pins 4 and 5 are V+ and V-, which are the negative and positive poles of the power supply terminal respectively. In the present invention, they are connected to -15V and +15V respectively. Pin 5 is COMP, which is used to compensate the frequency response of the amplifier and optimize its stability and performance. Pin 7 is OUT, the amplifier output terminal. The present invention outputs a high-frequency temperature control signal, and the output path is the standard BNC interface at the P1 end. Under high-power drive, the LT1210 will generate heat, and a corresponding air-cooled radiator is equipped. Its core function is high-power signal amplification, with high bandwidth and high current output.

[0063] As Figure 5 As shown: The voltage regulator circuit uses an LM2596T switching voltage regulator design. Pin 1 is VIN, the input terminal is used to connect the input voltage source. In the present invention, it is connected to +15V. Pin 1 is OUTPUT, the output terminal provides the voltage after step-down conversion. Pin 3 is GND, the ground terminal. Pin 4 is FB, which is connected to the feedback circuit to help control the output voltage. Pin 5 is ON# / OFF, which is used to enable or disable the chip. This circuit converts the input voltage +15V into a stable +12V output to provide a stable drive voltage for the air-cooled radiator. It has built-in protection functions, which improve the stability and safety of the circuit. Through the combined filtering of L1 and C11 / C12, it effectively smooths the output current and voltage and reduces the ripple. Its main function is high-efficiency step-down.

[0064] The content not described in detail in the specification of the present invention belongs to the prior art well-known to those skilled in the art. It is hereby specified that the above description helps those skilled in the art to understand the present invention, but does not limit the protection scope of the present invention. Any implementation that is an equivalent replacement, modification, improvement, and / or simplification of the above description without departing from the essence of the present invention falls within the protection scope of the present invention.

Claims

1. A temperature control device for a non-magnetic packaged VCSEL laser, characterized in that: The first layer 2 is distributed on the upper surface of the aluminum nitride ceramic package substrate. N The polar distance heating film, N is a positive integer, is distributed on the lower surface of the aluminum nitride ceramic package substrate and the first layer 2 N The second layer 2 of the polar heating film in series N Polar distance heating film, in the first layer 2 N The center of the polar heating film is provided with a VCSEL laser and an NTC negative feedback thermistor. N The inter-pole heating film is connected to the output end of the multiplier through the second-stage power amplifier circuit and the first-stage voltage amplifier circuit in sequence, the first input end of the multiplier is connected to the PID temperature control signal output end of the main control module, the second input end of the multiplier is connected to the sinusoidal modulation signal output end of the function generator, and the NTC negative feedback thermistor is connected to the PID temperature feedback signal input end of the main control module.

2. The temperature control device for non-magnetic packaged VCSEL laser according to claim 1, characterized in that: The second-stage power amplifier circuit is equipped with an air-cooled heat sink, and the second-stage power amplifier circuit outputs a high-frequency sinusoidal temperature control signal to the double-layer 2 N The polar spacing heating film, the air-cooled radiator is connected to the output end of the switching power supply through a voltage stabilizing circuit, the output end of the switching power supply is respectively connected to the second-stage power amplifier circuit and the first-stage voltage amplifier circuit, the input end of the switching power supply is connected to 220V AC, and the output voltage of the output end of the switching power supply is ±15V.

3. The temperature control device for non-magnetic packaged VCSEL laser according to claim 1, characterized in that: The main control module includes a host computer panel and a NIDAQ data acquisition processor. The NIDAQ data acquisition processor includes a data acquisition card and a host computer program. The data acquisition card is used to collect temperature signals. The host computer program is used to monitor real-time temperature curves, desired temperature settings, and PID parameter settings and adjustments. The host computer program is built on a LabVIEW development environment.

4. The temperature control device for non-magnetic packaged VCSEL laser according to claim 1, characterized in that: The PID temperature control signal output by the main control module has the following expression: Where u(t) is the PID temperature control signal, t represents time, e is the difference between the temperature setting value and the temperature measurement value, K c is the proportionality coefficient, T i is the integration time constant, T d is the differential time constant.

5. The temperature control device for non-magnetic packaged VCSEL laser according to claim 1, characterized in that: The NTC negative feedback thermistor includes the following relationship: Where T represents temperature, R T is the resistance value at temperature T, T0 is the reference temperature, R0 is the resistance value at reference temperature T0, B is the material constant, and e is the natural constant.

6. The temperature control device for non-magnetic packaged VCSEL laser according to claim 1, characterized in that: The second-stage power amplifier circuit includes an LT1210CR operational amplifier.

7. The temperature control device for non-magnetic packaged VCSEL laser according to claim 1, characterized in that: The first-stage voltage amplification circuit includes an OP27GS operational amplifier.

8. The temperature control device for non-magnetic packaged VCSEL laser according to claim 2, characterized in that: The voltage stabilizing circuit includes an LM2596T switching regulator.

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