A high-precision tunable laser control system based on pulse width regulation

Abstract

The present invention provides a high-precision tunable laser control system based on pulse-width modulation, which relates to the field of electronic digital data processing. The system includes a pulse-width modulation module, a laser driving module, an optical tuning module, a feedback control module, and a human-computer interaction module. The pulse-width modulation module is used to dynamically adjust the pulse width. The laser driving module is used to drive and generate laser light. The optical tuning module is used to adjust the wavelength of the laser. The feedback control module is used to monitor the output laser and perform feedback adjustment. The human-computer interaction module is used to set laser parameters. The present invention can analyze and calculate based on real-time errors, and feedback the analysis results to the control components for adjustment, so as to achieve high-precision laser output.

Description

Technical Field

[0001] The present invention belongs to the field of electrical digital data processing, and particularly relates to a high-precision tunable laser control system based on pulse width regulation. Background Art

[0002] With the rapid development of optoelectronic technology and laser technology, tunable lasers are increasingly widely used in the fields of optical communication, spectral analysis, precision measurement, medical diagnosis, etc. Tunable lasers can output lasers of different wavelengths according to requirements. Due to their flexible wavelength tunability, high precision, and strong stability, they have become an important part of modern optoelectronic systems. However, in practical applications, traditional laser control systems still have problems in terms of wavelength tuning accuracy, dynamic response speed, and stability.

[0003] Currently, many laser control systems have been developed. For example, the system disclosed in the Chinese patent with the publication number CN109802298B includes a monolithic integrated voltage-controlled constant current source drive circuit, an optical wavelength locking circuit, a high-precision TEC control circuit, a DSP chip, and a light source module. The DSP chip adjusts the integrated constant current source drive chip in the monolithic integrated voltage-controlled constant current source drive circuit through the SPI bus; the high-precision TEC circuit is used to control the operating environment temperature of the laser to be constant at a set value; it is set by the DSP chip outputting a voltage value to the corresponding pin of the temperature control chip through the DA function or directly changing the corresponding resistor in the circuit around the temperature control chip; the optical wavelength locking circuit collects two current values output by the light source module, converts them into voltages, and converts them into digital signals through the AD module and sends them to the DSP chip or directly inputs them into the AD module built in the DSP chip for acquisition, which is used for feedback control to compensate the output of the constant current source and ensure the stability of the wavelength and power output of the laser module. However, the control accuracy of the laser parameters of this system is not precise enough, especially for the control of deviations, and it is difficult to meet the high-precision requirements. Summary of the Invention

[0004] To solve the above technical problems, the present invention provides a high-precision tunable laser control system based on pulse width regulation, which can analyze and calculate based on real-time errors, feedback the analysis results to the control component for adjustment, and achieve high-precision laser output.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A high-precision tunable laser control system based on pulse width regulation includes a pulse width regulation module, a laser drive module, an optical tuning module, a feedback control module, and a human-machine interaction module;

[0007] The human-computer interaction module is used to set target wavelength, power, and pulse width parameters; the pulse width regulation module generates corresponding drive signals according to the settings of the human-computer interaction module; the laser drive module excites the laser to output optical signals according to the drive signals; the optical tuning module dynamically adjusts the laser wavelength to the target value; the feedback control module monitors the output in real time and performs correction processing;

[0008] The pulse width regulation module includes a pulse width generation unit. The pulse width generation unit generates a drive signal with adjustable pulse width according to preset parameters, and combines signal modulation and timing control to achieve fine adjustment of laser output;

[0009] The optical tuning module includes a grating tuning unit and a loop compensation unit. The grating tuning unit realizes precise spectral range scanning through a microelectromechanical system, and the loop compensation unit is used to eliminate the dynamic error introduced by mechanical adjustment;

[0010] The feedback control module includes a closed-loop control unit. The closed-loop control unit adjusts parameters based on the detection signal and feeds them back to the laser drive module and the optical tuning module to achieve closed-loop control.

[0011] Further, the pulse width regulation module further includes a signal modulation unit and a timing control unit. The signal modulation unit is used to adjust the frequency and amplitude of the drive signal, and the timing control unit is used to control the trigger time of the pulse signal;

[0012] The laser drive module includes a power regulation unit and a current drive unit. The power regulation unit dynamically adjusts the drive current according to the pulse width signal, and the current drive unit transmits the adjusted current signal to the laser and generates a highly stable optical output.

[0013] Further, the optical tuning module further includes a wavelength selection unit. The wavelength selection unit cooperates with a multimode interference filter to accurately extract the optical signal of the target wavelength.

[0014] Further, the feedback control module includes an optical power detection unit and a closed-loop control unit. The optical power detection unit monitors the power and wavelength of the laser output in real time through a photodiode, and the closed-loop control unit adjusts parameters based on the detection signal and feeds them back to the laser drive module and the optical tuning module.

[0015] Further, the human-computer interaction module includes an interface display unit and a parameter setting unit. The interface display unit is used to display the actual status information of the laser, and the parameter setting unit is used to input control parameters.

[0016] Furthermore, the grating tuning unit includes a grating element, a rotation adjustment mechanism, and a position sensor. The grating element is used to achieve diffraction and separate the wavelengths of incident light. The rotation adjustment mechanism is used to adjust the grating angle and dynamically change the direction of diffracted light. The position sensor is used to detect the grating angle in real time and provide feedback.

[0017] Furthermore, the closed-loop control unit includes an error detector, a control calculation processor, and an execution drive processor. The error detector is used to detect the error between the actual value and the target value and generate an error signal. The control calculation processor is used to calculate the adjustment strategy. The execution driver is used to transmit the adjustment signal to the execution component.

[0018] Furthermore, the control calculation processor calculates the adjustment angle of the grating according to the following formula :

[0019] ;

[0020] where m is the diffraction order, is the wavelength deviation, d is the grating period, is the current grating diffraction angle.

[0021] Furthermore, the control calculation processor calculates the adjusted drive current I according to the following formula new :

[0022] ;

[0023] where, is the power deviation, is the laser efficiency, I c is the current drive current.

[0024] Beneficial effects:

[0025] The present invention utilizes high-precision pulse-width modulation technology, that is, by using a drive signal with adjustable pulse width, combined with signal modulation and timing control, to achieve fine adjustment of laser output and improve the stability of laser power and wavelength. The present invention also adopts intelligent feedback closed-loop control, that is, through optical power detection and closed-loop control, it monitors the laser output in real time and dynamically adjusts the drive current and optical tuning parameters to achieve precise power and wavelength control, effectively reducing the impact of environmental interference on system performance. The present invention can achieve high-precision and fast response of optical tuning, that is, by combining grating tuning and multimode interference filtering, and using a microelectromechanical system to dynamically scan the spectrum, it realizes nanometer-level wavelength resolution and fast wavelength switching, improving system adaptability. After the laser is output, the present invention detects the laser state and calculates the deviation, and adjusts the control parameters based on the deviation. When adjusting the control parameters, it does not directly adjust based on the deviation, but calculates and processes the deviation before adjusting, making the adjustment more accurate and meeting the high-demand laser requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a schematic diagram of the overall structural framework of the high-precision tunable laser control system based on pulse-width modulation of the present invention;

[0027] Figure 2 is a schematic diagram of the composition of the pulse-width modulation module;

[0028] Figure 3 is a schematic diagram of the composition of the optical tuning module;

[0029] Figure 4 is a schematic diagram of the composition of the optical power detection unit;

[0030] Figure 5 is a schematic diagram of the composition of the closed-loop control unit;

[0031] Figure 6 is the actual test error effect diagram of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] The following specific embodiments are used to illustrate the implementation manners of the present invention. Those skilled in the art can understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the spirit of the present invention. Additionally, the drawings of the present invention are only simple schematic illustrations and are not drawn according to actual sizes, which is stated in advance. The following embodiments will further detail the related technical content of the present invention, but the disclosed content is not intended to limit the protection scope of the present invention.

[0033] Such as Figure 1As shown in the figure, this embodiment provides a high-precision tunable laser control system based on pulse width modulation, including a pulse width modulation module, a laser driving module, an optical tuning module, a feedback control module, and a human-computer interaction module.

[0034] The pulse width modulation module is used to dynamically adjust the pulse width, the laser driving module is used to drive the generation of laser, the optical tuning module is used to adjust the wavelength of the laser, the feedback control module is used to monitor the output laser and perform feedback adjustment, and the human-computer interaction module is used to set laser parameters.

[0035] As Figure 2 shown in the figure, the pulse width modulation module includes a pulse width generation unit, a signal modulation unit, and a timing control unit. The pulse width generation unit generates a driving signal with adjustable pulse width according to preset parameters. The signal modulation unit is used to adjust the frequency and amplitude of the driving signal. The timing control unit is used to control the trigger time of the pulse signal.

[0036] Preferably, the pulse width generation unit includes a clock generator, a pulse width controller, and a logic trigger. The clock generator is used to provide a stable reference time base. The pulse width controller generates a pulse signal with a specific width based on the pulse width parameter. The logic trigger is used to accurately start or stop the pulse generation process;

[0037] Preferably, the signal modulation unit includes a modulation controller, a modulation signal generator, and a mixer. The modulation controller is used to receive modulation parameters and manage the modulation method. The modulation signal generator is used to generate a fundamental wave signal for modulation. The mixer is used to mix the pulse signal with the fundamental wave signal;

[0038] Preferably, the timing control unit includes a clock divider, a delay adjuster, and a signal distributor. The clock divider is used to divide the high-frequency clock into the required low-frequency clock. The delay adjuster is used to add a delay to the clock signal for event synchronization. The signal distributor is used to distribute the timing signal to each module that needs to be controlled.

[0039] The laser driving module includes a power adjustment unit and a current driving unit. The power adjustment unit dynamically adjusts the driving current according to the pulse width signal. The current driving unit transmits the adjusted current signal to the laser and generates a highly stable optical output.

[0040] Preferably, the power adjustment unit includes a power controller and a protection circuit. The power controller is responsible for the overall calculation and adjustment of the power. The protection circuit is used to monitor overvoltage, overcurrent, etc. and trigger protection;

[0041] Preferably, the current driving unit includes a constant current source, a driving and amplifying processor, and a current monitoring processor. The constant current source is used to provide a basic current, the driving and amplifying processor is used to amplify the current signal, and the current monitoring processor is used to detect the output current in real time.

[0042] As Figure 3 shown, the optical tuning module includes a grating tuning unit, a wavelength selection unit, and a loop compensation unit. The grating tuning unit realizes precise spectral range scanning through a microelectromechanical system. The wavelength selection unit cooperates with a multimode interference filter to accurately extract the optical signal of the target wavelength. The loop compensation unit is used to eliminate the dynamic error introduced by mechanical adjustment.

[0043] Preferably, the grating tuning unit includes a grating element, a rotation adjustment mechanism, and a position sensor. The grating element is used to realize diffraction and separate the wavelengths of incident light. The rotation adjustment mechanism is used to adjust the grating angle to dynamically change the direction of diffracted light. The position sensor is used to detect the grating angle in real time and provide feedback.

[0044] Preferably, the wavelength selection unit includes an adjustable filter, a wavelength selection mirror group, and a signal detector. The adjustable filter is used to accurately pass the target wavelength and filter out other wavelengths. The wavelength selection mirror group is used to reflect and guide the optical signal of the target wavelength. The signal detector is used to verify the output wavelength and intensity.

[0045] Preferably, the loop compensation unit includes an environment detector, a compensation driver, and a filtering and suppression processor. The environment detector is used to monitor the influence of environmental interference on the system output. The compensation driver is used to adjust the physical system components. The filtering and suppression processor is used to suppress the high-frequency noise introduced during the compensation process.

[0046] The feedback control module includes an optical power detection unit and a closed-loop control unit. The optical power detection unit monitors the power and wavelength of the laser output in real time through a photodiode. The closed-loop control unit adjusts the parameters based on the detection signal and feeds back to the laser driving module and the optical tuning module.

[0047] As Figure 4 shown, the optical power detection unit includes a photodetector, a signal conditioning processor, and an output interface processor. The photodetector is used to convert the input optical signal into an electrical signal proportional to the power and wavelength. The signal conditioning processor is used to filter, shape, and normalize the converted electrical signal. The output interface processor is used to output the detected power signal to other modules.

[0048] As Figure 5As shown, the closed-loop control unit includes an error detector, a control calculation processor, and an execution drive processor. The error detector is used to detect the error between the actual value and the target value and generate an error signal. The control calculation processor is used to calculate the adjustment strategy, and the execution driver is used to transmit the adjustment signal to the execution component.

[0049] Preferably, the interface display unit includes a real-time information display processor and a deviation information display processor. The real-time information display processor is used to display the real-time status information of the laser and the physical component, and the deviation information display processor is used to display the deviation information of the laser.

[0050] Preferably, the parameter setting unit includes a parameter input processor and a parameter response processor. The parameter input processor is used to input parameter information, and the parameter response processor is used to collect the input parameter information and transmit it to the other modules.

[0051] The control calculation processor calculates the adjustment angle of the grating according to the following formula :

[0052] ;

[0053] where m is the diffraction order, is the wavelength deviation, d is the grating period, is the current grating diffraction angle.

[0054] The control calculation processor calculates the adjusted drive current I according to the following formula new :

[0055] ;

[0056] where, is the power deviation, is the laser efficiency, I c is the current drive current.

[0057] The control calculation processor calculates the adjusted pulse width trigger time t according to the following formula new :

[0058] ;

[0059] where t c is the current pulse width trigger time, is the pulse width deviation, and T is the set pulse width.

[0060] The human-machine interaction module includes an interface display unit and a parameter setting unit. The interface display unit is used to display the actual status information of the laser, and the parameter setting unit is used to input control parameters.

[0061] The working process of the high-precision tunable laser control system based on pulse-width modulation in the embodiments of the present invention includes the following steps:

[0062] S1. Set the target wavelength, power, and pulse-width parameters in the human-machine interaction module;

[0063] S2. Generate a corresponding drive signal using the pulse-width modulation module;

[0064] S3. Use the laser drive module to excite the laser to output an optical signal according to the drive signal;

[0065] S4. Use the optical tuning module to dynamically adjust the laser wavelength to the target value;

[0066] S5. Use the feedback control module to monitor the output in real time and perform correction processing;

[0067] Specifically, in S5, the control calculation processor of the feedback control module calculates the adjustment angle of the grating according to the following formula :

[0068] ;

[0069] where m is the diffraction order, is the wavelength deviation, d is the grating period, is the current grating diffraction angle;

[0070] The control calculation processor calculates the adjusted drive current I according to the following formula new :

[0071] ;

[0072] where, is the power deviation, is the laser efficiency, I c is the current drive current;

[0073] The control calculation processor calculates the adjusted pulse-width trigger time t according to the following formula new :

[0074] ;

[0075] where t c is the current pulse-width trigger time, is the pulse-width deviation, and T is the set pulse width.

[0076] Using the present invention to generate 10 lasers with different powers (i.e., as indicated by the numbers 1 - 10 in Figure 6 ), testing the actual values, and obtaining the comparative effect diagram shown in Figure 6 .

[0077] The above-disclosed content is only a preferred and feasible embodiment of the present invention, and does not limit the protection scope of the present invention. Therefore, all equivalent technical changes made by using the content of the specification and drawings of the present invention are included in the protection scope of the present invention. In addition, with the development of technology, the elements therein can be updated.

Claims

1. A high-precision tunable laser control system based on pulse width modulation, characterized in that, Through optical power detection and closed-loop control, the laser output is monitored in real time, and the drive current and optical tuning parameters are dynamically adjusted to achieve precise power and wavelength control; combined with grating tuning and multimode interference filtering, the microelectromechanical system is used to dynamically scan the spectrum to achieve nanometer-level wavelength resolution and fast wavelength switching, including: A pulse width regulation module, a laser drive module, an optical tuning module, a feedback control module, and a human-machine interaction module; The human-machine interaction module is used to set the target wavelength, power, and pulse width parameters; the pulse width regulation module generates corresponding drive signals according to the settings of the human-machine interaction module; the laser drive module excites the laser to output an optical signal according to the drive signal; the optical tuning module dynamically adjusts the laser wavelength to the target value; the feedback control module monitors the output in real time and performs correction processing; The pulse width regulation module includes a pulse width generation unit, which generates a drive signal with adjustable pulse width according to preset parameters, and combines signal modulation and timing control to achieve fine adjustment of the laser output; The optical tuning module includes a grating tuning unit and a loop compensation unit. The grating tuning unit realizes precise spectral range scanning through the microelectromechanical system, and the loop compensation unit is used to eliminate the dynamic error introduced by mechanical adjustment; The feedback control module includes a closed-loop control unit, which adjusts the parameters based on the detection signal and feeds back to the laser drive module and the optical tuning module to achieve closed-loop control; The closed-loop control unit includes a control computing processor, and the control computing processor calculates the adjustment angle of the grating according to the following formula : ； where m is the diffraction order, is the wavelength deviation, d is the grating period, is the current grating diffraction angle; The control computing processor calculates the adjusted drive current according to the following formula :[[]]END]] ； wherein, is the power deviation, is the laser efficiency, is the current drive current; The control computing processor calculates the adjusted pulse width trigger time t according to the following formula new :[[]]END]] ； where t c is the current pulse width trigger time, is the pulse width deviation, and T is the set pulse width.

2. The high-precision tunable laser control system based on pulse-width modulation according to claim 1, characterized in that, The pulse width regulation module further includes a signal modulation unit and a timing control unit. The signal modulation unit is used to adjust the frequency and amplitude of the drive signal, and the timing control unit is used to control the trigger time of the pulse signal; The laser drive module includes a power regulation unit and a current drive unit. The power regulation unit dynamically adjusts the drive current according to the pulse width signal, and the current drive unit transmits the adjusted current signal to the laser and generates a highly stable optical output.

3. A high-precision tunable laser control system based on pulse width modulation as claimed in claim 1, characterized in that The optical tuning module further includes a wavelength selection unit, which cooperates with the multimode interference filter to accurately extract the optical signal of the target wavelength.

4. A high-precision tunable laser control system based on pulse-width modulation according to claim 1, characterized in that, The feedback control module further includes an optical power detection unit, which monitors the power and wavelength of the laser output in real time through a photodiode.

5. A high-precision tunable laser control system based on pulse width modulation as claimed in claim 1, characterized in that, The human-machine interaction module includes an interface display unit and a parameter setting unit. The interface display unit is used to display the actual status information of the laser, and the parameter setting unit is used to input control parameters.

6. The high-precision tunable laser control system based on pulse-width modulation according to claim 3, wherein The grating tuning unit includes a grating element, a rotation adjustment mechanism, and a position sensor. The grating element is used to achieve diffraction and separate the wavelengths of the incident light. The rotation adjustment mechanism is used to adjust the grating angle and dynamically change the direction of the diffracted light. The position sensor is used to detect the grating angle in real time and feedback.

7. The high-precision tunable laser control system based on pulse width regulation according to claim 4, wherein The closed-loop control unit includes an error detector and an execution drive processor. The error detector is used to detect the error between the actual value and the target value and generate an error signal. The execution drive processor is used to transmit the adjustment signal to the execution component.

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