Multi-mode pumping noise suppressor and multi-mode pumping laser device

Abstract

The invention relates to a multimode pumping noise suppressor and multimode pumping laser equipment. The multimode pumping noise suppressor comprises a pumping driving module, a spatial light beam sampling module, a photoelectric conversion module and a signal processing module. The pumping driving module is used for generating a multi-mode pumping laser signal and outputting a light beam based on the multi-mode pumping laser signal; the spatial light beam sampling module is used for outputting a first light signal to a first output end along a reflection direction so as to carry out intensity sampling on the light beam, and is also used for outputting a second light signal to a second output end along a transmission direction; the photoelectric conversion module is used for converting the first optical signal into an electric signal; and the signal processing module is used for generating a control electric signal according to the electric signal and outputting the control electric signal, and the control electric signal is used for completing noise suppression of the multimode pumping laser signal through current intensity control.

Description

Technical Field

[0001] The present application relates to the field of laser control technology, and in particular to a multi-mode pump noise suppressor and a multi-mode pump laser device. Background Art

[0002] Multimode pump laser light source is a research direction that has attracted much attention in the field of laser technology, and its development has been in a state of continuous evolution. Multimode pump laser light source has the characteristics of multi-wavelength and high power output, and has a wide range of potential application value in many application fields, such as communications, medical treatment, scientific research, etc.

[0003] However, there are still some defects in multi-mode pump laser light sources. First, the beam quality of its output beam is still poor, and it cannot be well used in some applications with strict requirements on high beam quality. Secondly, the instability of intensity noise and frequency characteristics affects the feasibility of multi-mode pump laser light sources in fields with high requirements on light source stability, such as precision measurement and optical communication systems. In addition, multi-mode pump laser light sources are sensitive to the environment and are easily affected by factors such as temperature and vibration. These problems may cause multi-mode pump laser light sources to show limitations in some specific applications. Although existing pump noise suppressors can solve some problems, existing pump noise suppressors are mainly aimed at single-mode light sources. In the noise suppression of multi-mode pump laser light sources, the use of existing pump noise suppressors will inevitably introduce additional multi-mode interference, and the noise suppression effect is poor.

[0004] Therefore, how to improve the noise suppression effect of multi-mode pump laser light sources still needs to be solved. Summary of the invention

[0005] Based on this, it is necessary to provide a multi-mode pump noise suppressor that can improve the noise suppression effect of a multi-mode pump laser light source.

[0006] In a first aspect, the present application provides a multi-mode pump noise suppressor, comprising: a pump driving module, a spatial beam sampling module, a photoelectric conversion module and a signal processing module;

[0007] The output end of the pump driving module is connected to the input end of the spatial beam sampling module; the first output end of the spatial beam sampling module is connected to the input end of the photoelectric conversion module, the first output end is used to output a first optical signal, and the second output end is used to output a second optical signal; the output end of the photoelectric conversion module is connected to the input end of the signal processing module; the output end of the signal processing module is connected to the output end of the pump driving module;

[0008] The pump driving module is used to generate a multi-mode pump laser signal and output a light beam based on the multi-mode pump laser signal;

[0009] The spatial beam sampling module is used to output a first light signal to a first output end along a reflection direction to perform intensity sampling on the light beam, and is also used to output a second light signal to a second output end along a transmission direction;

[0010] The photoelectric conversion module is used to convert the first optical signal into an electrical signal;

[0011] The signal processing module is used to generate and output a control electric signal according to the electric signal, and the control electric signal is used to achieve noise suppression of the multi-mode pump laser signal by controlling the current intensity.

[0012] In one of the embodiments, the spatial beam sampling module includes: a first collimator, a spatial beam sampler, a spatial light attenuator, a second collimator and a convex lens;

[0013] The input end of the first collimator is connected to the output end of the pump driving module, and the output end is connected to the input end of the spatial beam sampler; the first output end of the spatial beam sampler is connected to the input end of the spatial light attenuator, and the second output end is connected to the input end of the second collimator; the output end of the spatial light attenuator is arranged corresponding to the concave surface of the optical convex lens, and the convex surface of the optical convex lens is arranged corresponding to the input end of the photoelectric converter; the concave surface of the optical convex lens transmits the first light signal; the output end of the second collimator is used to output the second light signal;

[0014] The first collimator is used to convert the light beam into parallel light in space;

[0015] The spatial beam sampler is used to output the parallel light as a first parallel light to the second output end according to the transmission direction, and to output a part of the parallel light as a second parallel light to the first output end according to the reflection direction;

[0016] The spatial light attenuator is used to adjust the power of the first parallel light;

[0017] The optical convex lens is used to focus and convert the first parallel light into a first optical signal.

[0018] In one of the embodiments, the light reflectivity of the spatial beam sampler is 2%; the maximum attenuation of the spatial light attenuator is 20 decibels; and the focal length of the optical convex lens is 50 mm.

[0019] In one of the embodiments, the photoelectric conversion module includes: a spatial photoelectric detector and a one-dimensional translation stage;

[0020] The one-dimensional displacement stage is used to adjust the relative position of the spatial photoelectric detector and the optical convex lens;

[0021] The spatial photoelectric detector is used to convert the first optical signal into an electrical signal carrying intensity noise fluctuations, and output the electrical signal to the signal processing module via a radio frequency line.

[0022] In one embodiment, the input voltage of the spatial photodetector is 12 volts, the response speed is 10 MHz, the maximum voltage of the electrical signal is 1 volt, and the maximum power of the first optical signal is 4 milliwatts.

[0023] In one of the embodiments, the signal processing module includes: a stable voltage reference source generating unit and a control signal generating unit;

[0024] The stable voltage reference source generating unit is used to generate a negative voltage signal with noise, and is also used to adjust the magnitude of the negative voltage signal;

[0025] The control signal generating unit is used to compare the electrical signal output by the photoelectric conversion module with the negative voltage signal, and obtain the control electrical signal with noise signal compensation information according to the comparison result.

[0026] In one embodiment, the stable voltage reference source generating unit is used to adjust the magnitude of the negative voltage signal within a range between 0 volts and 10 volts.

[0027] In one of the embodiments, the pump driving module includes: a pump driving and a multi-mode pump light source;

[0028] The input end of the pump driver is connected to the output end of the signal processing module, and the output end is connected to the multi-mode pump light source;

[0029] The pump driver is used to drive the multi-mode pump light source according to the control electrical signal output by the signal processing module;

[0030] The multi-mode pump light source is used to generate a multi-mode pump laser signal and output a light beam based on the multi-mode pump laser signal.

[0031] In one of the embodiments, the pump driving module further includes: a pump light source direct control unit and an external electrical signal modulation unit;

[0032] The pump light source direct control unit is used to supply power to the multi-mode pump light source and to control the power of the multi-mode pump light source;

[0033] The external electrical signal modulation unit is used to receive an external electrical signal and control the power of the multi-mode pump light source based on the external electrical signal and its own electrical signal.

[0034] In a second aspect, the present application provides a multi-mode pump laser device, comprising the multi-mode pump noise suppressor as described in the first aspect, configured to output a second optical signal.

[0035] The above-mentioned multimode pump noise suppressor and multimode pump laser equipment realize noise suppression of multimode pump laser based on spatial light structure. This spatial light structure adopts spatial light intensity reflection sampling, does not introduce multimode interference noise in multimode optical fiber, has pure light intensity information sampling capability, and will not cause noise suppression failure due to environmental vibration noise and mode field asymmetry. Therefore, the multimode pump noise suppressor provided in this application can successfully realize intensity noise suppression of multimode pump laser. In addition, the multimode pump noise suppressor has a simple structure and stable performance, and is suitable for various multimode pump light source intensity noise suppression scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0037] FIG1 is a multi-mode pump noise suppressor according to an embodiment;

[0038] FIG. 2 is a module structure of the spatial beam sampling module in FIG. 1 ;

[0039] FIG3 is a module structure of the photoelectric conversion module in FIG1 ;

[0040] FIG4 is a module structure of the signal processing module in FIG1 ;

[0041] FIG5 is a module structure of the pump driving module in FIG1 ;

[0042] FIG. 6 shows another module structure of the pump driving module in FIG. 1 .

[0043] Description of reference numerals:

[0044] 10. Multimode pump noise suppressor; 11. Pump driving module; 12. Spatial beam sampling module; 13. Photoelectric conversion module; 14. Signal processing module;

[0045] 111. Pump driver; 112. Multi-mode pump light source; 113. Pump light source direct control unit; 114. External electrical signal modulation unit;

[0046] 121, a first collimator; 122, a spatial beam sampler; 123, a spatial light attenuator; 124, a second collimator; 125, a convex lens;

[0047] 131. Space photoelectric detector; 132. One-dimensional translation stage;

[0048] 141. Stable voltage reference source generating unit; 142. Control signal generating unit. DETAILED DESCRIPTION

[0049] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0050] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0051] It is understood that the terms "first", "second", etc. used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0052] It can be understood that the “connection” in the following embodiments should be understood as “electrical connection”, “communication connection”, etc. if the connected circuits, modules, units, etc. have electrical signals or data transmission between each other.

[0053] It can be understood that “at least one” means one or more, “plurality” means two or more, and “at least a portion of an element” means a part or all of an element.

[0054] When used herein, the singular forms "a", "an", and "the" may also include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" and the like specify the presence of stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the relevant listed items.

[0055] Multimode pump laser light source is a research direction that has attracted much attention in the field of laser technology, and its development has been in a state of continuous evolution. Multimode pump laser light source has the characteristics of multi-wavelength and high power output, and has a wide range of potential application value in many application fields, such as communications, medical treatment, scientific research, etc.

[0056] However, there are still some defects in multi-mode pump laser light sources. First, the beam quality of its output beam is still poor, and it cannot be well used in some applications with strict requirements on high beam quality. Secondly, the instability of intensity noise and frequency characteristics affects the feasibility of multi-mode pump laser light sources in fields with high requirements on light source stability, such as precision measurement and optical communication systems. In addition, multi-mode pump laser light sources are sensitive to the environment and are easily affected by factors such as temperature and vibration. These problems may cause multi-mode pump laser light sources to show limitations in some specific applications. Although existing pump noise suppressors can solve some problems, existing pump noise suppressors are mainly aimed at single-mode light sources. In the noise suppression of multi-mode pump laser light sources, the use of existing pump noise suppressors will inevitably introduce additional multi-mode interference, and the noise suppression effect is poor.

[0057] In order to solve the above problems, the present application provides a multi-mode pump noise suppressor, which includes a pump driving module, a spatial beam sampling module, an optoelectronic conversion module and a signal processing module. The pump driving module is used to generate a multi-mode pump laser signal and output a light beam based on the multi-mode pump laser signal. The spatial beam sampling module is used to output a first light signal to a first output end along a reflection direction to perform intensity sampling on the light beam, and is also used to output a second light signal to a second output end along a transmission direction. The optoelectronic conversion module is used to convert the first light signal into an electrical signal. The signal processing module is used to generate and output a control electrical signal according to the electrical signal, and the control electrical signal is used to complete the noise suppression of the multi-mode pump laser signal through current intensity control.

[0058] Thus, noise suppression of multimode pump laser is achieved based on spatial optical structure. This spatial optical structure adopts spatial light intensity reflection sampling, does not introduce multimode interference noise in multimode optical fiber, has pure light intensity information sampling capability, and does not cause noise suppression failure due to environmental vibration noise and mode field asymmetry. Therefore, the multimode pump noise suppressor provided in this application can successfully achieve intensity noise suppression of multimode pump laser. In addition, the multimode pump noise suppressor has a simple structure and stable performance, and is suitable for various multimode pump light source intensity noise suppression scenarios.

[0059] As shown in FIG. 1 , a multi-mode pump noise suppressor 10 according to an embodiment includes a pump driving module 11 , a spatial beam sampling module 12 , a photoelectric conversion module 13 and a signal processing module 14 .

[0060] The output end of the pump driving module 11 is connected to the input end of the spatial beam sampling module 12. The pump driving module 11 is used to generate a multi-mode pump laser signal and output a beam based on the multi-mode pump laser signal.

[0061] The pump driving module 11 is provided with a multimode pump light source 112 . The pump driving module 11 generates an electrical signal to drive the multimode pump light source 112 . The multimode pump light source 112 generates an optical signal that enters the multimode optical fiber and outputs an optical beam through the multimode optical fiber.

[0062] The first output end of the spatial beam sampling module 12 is connected to the input end of the photoelectric conversion module 13, the first output end is used to output the first light signal, and the second output end is used to output the second light signal. The spatial beam sampling module 12 is used to output the first light signal to the first output end along the reflection direction to perform intensity sampling on the light beam. The spatial beam sampling module 12 is also used to output the second light signal to the second output end along the transmission direction. The spatial beam sampling module 12 performs intensity sampling on the light beam and divides the light signal into two directions, transmission and reflection. The transmission direction is directly input as an external light source, and the reflection direction will enter the photoelectric conversion module 13. The reflectivity of the spatial beam sampling module 12 represents the sampling rate when the spatial beam sampling module 12 performs intensity sampling. The spatial beam sampling module 12 performs optical splitting output and sampling through spatial light to ensure that the intensity information of the first light signal obtained by sampling is completely consistent with the intensity information of the output second light signal.

[0063] The output end of the photoelectric conversion module 13 is connected to the input end of the signal processing module 14. The photoelectric conversion module 13 is used to convert the first optical signal into an electrical signal. Optionally, the photoelectric conversion module 13 may include a spatial photodetector 131, which can convert the first optical signal with intensity noise into an electrical noise signal with intensity noise fluctuation, and transmit the electrical noise signal to the signal processing module 14 via a radio frequency line. The electrical noise signal is the electrical signal output by the photoelectric conversion module 13, and the electrical signal is a direct current electrical signal.

[0064] The output end of the signal processing module 14 is connected to the output end of the pump driving module 11. The signal processing module 14 is used to generate and output a control electric signal according to the electric signal, and the control electric signal is used to complete the noise suppression of the multi-mode pump laser signal by current intensity control. The control electric signal is a nearly 0V control signal with noise signal compensation information, which is used to compensate for the noise signal in the driving voltage of the multi-mode pump light source 112. The signal processing module 14 can be an integrated module to avoid additional noise.

[0065] The multimode pump noise suppressor 10 provided in this embodiment realizes noise suppression of multimode pump laser based on spatial light structure. This spatial light structure adopts spatial light intensity reflection sampling, does not introduce multimode interference noise in multimode optical fiber, has pure light intensity information sampling capability, and will not cause noise suppression failure due to environmental vibration noise and mode field asymmetry. Therefore, the multimode pump noise suppressor 10 provided in this embodiment can successfully realize intensity noise suppression of multimode pump laser. In addition, the multimode pump noise suppressor 10 has a simple structure and stable performance, and is suitable for various multimode pump light source 112 intensity noise suppression scenarios.

[0066] As shown in FIG. 2 , in one embodiment, the spatial beam sampling module 12 includes a first collimator 121 , a spatial beam sampler 122 , a spatial light attenuator 123 , a second collimator 124 and a convex lens 125 .

[0067] The input end of the first collimator 121 is connected to the output end of the pump driving module 11, and the output end is connected to the input end of the spatial beam sampler 122. The first collimator 121 is used to convert the light beam into parallel light in space. The first collimator 121 can also be understood as a first collimating mirror.

[0068] The first output end of the spatial beam sampler 122 is connected to the input end of the spatial light attenuator 123 , and the second output end is connected to the input end of the second collimator 124 .

[0069] The output end of the spatial light attenuator 123 is arranged corresponding to the concave surface of the optical convex lens 125, and the convex surface of the optical convex lens 125 is arranged corresponding to the input end of the photoelectric converter.

[0070] The concave surface of the optical convex lens 125 transmits the first optical signal.

[0071] The output end of the second collimator 124 is used to output the second optical signal. The second collimator 124 can also be understood as a second collimating lens.

[0072] The spatial beam sampler 122 is used to output the first parallel light to the second output end according to the transmission direction of the parallel light, and to output the second parallel light to the first output end according to the reflection direction of part of the parallel light. The spatial beam sampler 122 can also be understood as a spatial beam sampling mirror.

[0073] The spatial light attenuator 123 is used to adjust the power of the first parallel light. The spatial light attenuator 123 can also be understood as a spatial light attenuation plate.

[0074] The optical convex lens 125 is used to focus and convert the first parallel light into a first optical signal.

[0075] That is to say, after the pump driving module 11 outputs the light beam, the light beam passes through the first collimator 121, so that the light beam is converted into parallel light in space. After passing through the spatial beam sampler 122, the parallel light is divided into two directions of transmission and reflection, wherein the transmission direction is converted into light beams as the multi-mode pump output of the overall structure after passing through the second collimator, and the reflection direction is adjusted in power by the spatial light attenuator 123, and then the parallel light is converted into focused light by the optical convex lens 125, and then enters the photoelectric conversion module 13.

[0076] Optionally, the light reflectivity of the spatial beam sampler 122 is two percent (2%), that is, the sampling rate of the intensity sampling performed by the spatial beam sampling module 12 is 2%.

[0077] The maximum attenuation of the spatial optical attenuator 123 is 20 decibels (20 dB).

[0078] The focal length of the optical convex lens 125 is fifty millimeters (50 mm).

[0079] As shown in FIG. 3 , in one embodiment, the photoelectric conversion module 13 includes a spatial photoelectric detector 131 and a one-dimensional translation stage 132 .

[0080] The one-dimensional translation stage 132 is used to adjust the relative position of the spatial photodetector 131 and the optical convex lens 125. The relative position of the spatial photodetector and the optical convex lens 125 in the spatial beam sampling module 12 can be adjusted by the one-dimensional translation stage 132 to ensure that all light beams transmitted from the optical convex lens 125 can be focused to the light response area of ​​the spatial photodetector 131.

[0081] The spatial photoelectric detector 131 is used to convert the first optical signal into an electrical signal carrying intensity noise fluctuations, and output the electrical signal to the signal processing module 14 via a radio frequency line.

[0082] The spatial photoelectric detector 131 converts the first optical signal with intensity noise into an electrical noise signal with intensity noise fluctuation, and transmits the electrical noise signal to the signal processing module 14 via a radio frequency line.

[0083] Optionally, the maximum displacement range of the one-dimensional translation stage 132 is 3 cm, the input voltage of the spatial light detector is 12 volts (12V), the response rate is 10 megahertz (10MHz), the maximum output is 1 volt (1V), and the maximum input light is 4 milliwatts (mW).

[0084] As shown in FIG. 4 , in one embodiment, the signal processing module 14 includes a stable voltage reference source generating unit 141 and a control signal generating unit 142 .

[0085] The stable voltage reference source generating unit 141 is used to generate a negative voltage signal with noise and to adjust the magnitude of the negative voltage signal. The control signal generating unit 142 is used to compare the electrical signal output by the photoelectric conversion module 13 with the negative voltage signal and obtain the control electrical signal with noise signal compensation information according to the comparison result.

[0086] That is, the signal processing module 14 mainly includes a stable voltage reference source generating unit 141 and a control signal generating unit 142. The stable voltage reference source generating unit 141 can generate a negative voltage signal with ultra-low noise, and can adjust the negative voltage of the negative voltage signal so that the negative voltage signal is balanced with the electrical signal output by the photoelectric conversion module 13. The control signal generating unit 142 can compare and process the electrical signal output by the photoelectric conversion module 13 with the negative voltage signal, and finally obtain a control electrical signal. The control electrical signal is a nearly 0V control signal with noise signal compensation information. The signal processing module 14 is also used to transmit the control electrical signal to the external electrical signal input port in the pump driving module 11.

[0087] Optionally, the stable voltage reference source generating unit 141 is used to adjust the magnitude of the negative voltage signal within a range between 0 volts and 10 volts. That is, the adjustment range of the negative voltage signal generated by the signal processing module 14 is 0V-10V. The control electrical signal output by the signal processing module 14 can achieve a modulation speed of up to 10 kilohertz (kHz).

[0088] The signal processing module 14 can be an integrated module, which is directly integrated by the stable voltage reference source generating unit 141 and the control signal generating unit 142, avoiding the additional noise introduced by the separation of the reference signal and the processing structure. The reference signal includes the electrical signal output by the above-mentioned photoelectric conversion module 13.

[0089] As shown in FIG. 5 , in one embodiment, the pump driving module 11 includes a pump driver 111 and a multi-mode pump light source 112 .

[0090] The input end of the pump driver 111 is connected to the output end of the signal processing module 14 , and the output end is connected to the multi-mode pump light source 112 .

[0091] The pump driver 111 is used to drive the multi-mode pump light source 112 according to the control electrical signal output by the signal processing module 14. The multi-mode pump light source 112 is used to generate a multi-mode pump laser signal and output a light beam based on the multi-mode pump laser signal.

[0092] It should be noted that the pump driver 111 itself generates a driving voltage, which is used to drive the multi-mode pump light source 112. The driving voltage has noise (or noise disturbance voltage), and the control electrical signal is used to suppress the noise in the driving voltage, or to compensate for the noise disturbance voltage.

[0093] As shown in Fig. 6, in one embodiment, the pump driving module 11 further includes a pump light source direct control unit 113 and an external electrical signal modulation unit 114. The pump light source direct control unit 113 and the external electrical signal modulation unit 114 are located in independent modules.

[0094] The pump light source direct control unit 113 is used to power the multi-mode pump light source 112 and to control the power of the multi-mode pump light source 112. The pump light source direct control unit 113 can control the second optical signal output by the multi-mode pump noise suppressor 10 to adapt to different application scenarios by controlling the power of the multi-mode pump light source 112. Specifically, the pump light source direct control unit 113 can directly power the multi-mode pump light source 112 so that the multi-mode pump light source 112 generates multi-mode continuous pump light (i.e., a multi-mode pump laser signal), and controls the power of the multi-mode pump laser signal by adjusting the current. The pump light source direct control unit 113 is powered by 220V AC and can generate a DC signal of 0V to 4V, with a maximum modulation response speed of 10kHz.

[0095] The external electrical signal modulation unit 114 is used to receive an external electrical signal and control the power of the multimode pump light source 112 based on the external electrical signal and the internal electrical signal. Specifically, the external electrical signal modulation function can mix the external electrical signal with the internal electrical signal to control the multimode pump light source 112.

[0096] In summary, the multi-mode pump noise suppressor 10 provided in the embodiment of the present application adopts mature and stable optical principles, combines advanced processes of space optics, fiber optics, and electronics, performs light splitting, sampling, and photoelectric conversion through spatial light, and then generates a control signal through a reference voltage and processing structure integrated module, and finally achieves the suppression of the noise of the multi-mode pump light source 112. At the same time, the multi-mode pump noise suppressor 10 has a small structure, high stability, and significant feedback effect, and can be directly integrated into various devices or systems using multi-mode pumps as light sources. The multi-mode pump noise suppressor 10 can realize the application of ultra-low noise multi-mode pump light sources 112.

[0097] An embodiment of the present application further provides a multi-mode pump laser device, comprising the multi-mode pump noise suppressor provided in any of the above embodiments. The multi-mode pump laser device is used to output the second optical signal described in the above embodiments.

[0098] The multimode pump laser device realizes noise suppression of the multimode pump laser based on the spatial light structure. This spatial light structure adopts spatial light intensity reflection sampling, does not introduce multimode interference noise in the multimode optical fiber, has pure light intensity information sampling capability, and does not cause noise suppression failure due to environmental vibration noise and mode field asymmetry. Therefore, the multimode pump laser device provided in this embodiment can successfully realize intensity noise suppression of the multimode pump laser. In addition, the multimode pump laser device has a simple structure and stable performance, and is suitable for noise suppression scenarios of various multimode pump laser devices.

[0099] In the description of this specification, the description with reference to the terms "some embodiments", "other embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic description of the above terms does not necessarily refer to the same embodiment or example.

[0100] The technical features of the above embodiment can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above embodiment are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0101] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A multimode pump noise suppressor, characterized in that: include: Pump driving module, spatial beam sampling module, photoelectric conversion module and signal processing module; The output end of the pump driving module is connected to the input end of the spatial beam sampling module; the first output end of the spatial beam sampling module is connected to the input end of the photoelectric conversion module, the first output end is used to output a first optical signal, and the second output end is used to output a second optical signal; the output end of the photoelectric conversion module is connected to the input end of the signal processing module; the output end of the signal processing module is connected to the output end of the pump driving module; The pump driving module is used to generate a multi-mode pump laser signal and output a light beam based on the multi-mode pump laser signal; The spatial beam sampling module is used to output a first light signal to a first output end along a reflection direction to perform intensity sampling on the light beam, and is also used to output a second light signal to a second output end along a transmission direction; The photoelectric conversion module is used to convert the first optical signal into an electrical signal; The signal processing module is used to generate and output a control electric signal according to the electric signal, and the control electric signal is used to achieve noise suppression of the multi-mode pump laser signal by controlling the current intensity.

2. The multi-mode pump noise suppressor according to claim 1, characterized in that: The spatial beam sampling module comprises: a first collimator, a spatial beam sampler, a spatial light attenuator, a second collimator and a convex lens; The input end of the first collimator is connected to the output end of the pump driving module, and the output end is connected to the input end of the spatial beam sampler; the first output end of the spatial beam sampler is connected to the input end of the spatial light attenuator, and the second output end is connected to the input end of the second collimator; the output end of the spatial light attenuator is arranged corresponding to the concave surface of the optical convex lens, and the convex surface of the optical convex lens is arranged corresponding to the input end of the photoelectric converter; the concave surface of the optical convex lens transmits the first light signal; the output end of the second collimator is used to output the second light signal; The first collimator is used to convert the light beam into parallel light in space; The spatial beam sampler is used to output the parallel light as a first parallel light to the second output end according to the transmission direction, and to output a part of the parallel light as a second parallel light to the first output end according to the reflection direction; The spatial light attenuator is used to adjust the power of the first parallel light; The optical convex lens is used to focus and convert the first parallel light into a first optical signal.

3. The multi-mode pump noise suppressor according to claim 2, characterized in that: The light reflectivity of the spatial beam sampler is 2%; the maximum attenuation of the spatial light attenuator is 20 decibels; and the focal length of the optical convex lens is 50 mm.

4. The multi-mode pump noise suppressor according to claim 2, characterized in that: The photoelectric conversion module includes: a spatial photoelectric detector and a one-dimensional displacement stage; The one-dimensional displacement stage is used to adjust the relative position of the spatial photoelectric detector and the optical convex lens; The spatial photoelectric detector is used to convert the first optical signal into an electrical signal carrying intensity noise fluctuations, and output the electrical signal to the signal processing module via a radio frequency line.

5. The multi-mode pump noise suppressor according to claim 4, characterized in that: The input voltage of the spatial photoelectric detector is 12 volts, the response speed is 10 MHz, the maximum voltage of the electrical signal is 1 volt, and the maximum power of the first optical signal is 4 milliwatts.

6. The multi-mode pump noise suppressor according to any one of claims 1 to 5, characterized in that: The signal processing module includes: a stable voltage reference source generating unit and a control signal generating unit; The stable voltage reference source generating unit is used to generate a negative voltage signal with noise, and is also used to adjust the magnitude of the negative voltage signal; The control signal generating unit is used to compare the electrical signal output by the photoelectric conversion module with the negative voltage signal, and obtain the control electrical signal with noise signal compensation information according to the comparison result.

7. The multi-mode pump noise suppressor according to claim 6, characterized in that: The stable voltage reference source generating unit is used to adjust the magnitude of the negative voltage signal within a range between 0 volts and 10 volts.

8. The multi-mode pump noise suppressor according to any one of claims 1 to 5, characterized in that: The pump driving module includes: a pump driving and a multi-mode pump light source; The input end of the pump driver is connected to the output end of the signal processing module, and the output end is connected to the multi-mode pump light source; The pump driver is used to drive the multi-mode pump light source according to the control electrical signal output by the signal processing module; The multi-mode pump light source is used to generate a multi-mode pump laser signal and output a light beam based on the multi-mode pump laser signal.

9. The multi-mode pump noise suppressor according to claim 8, characterized in that: The pump driving module further includes: a pump light source direct control unit and an external electrical signal modulation unit; The pump light source direct control unit is used to supply power to the multi-mode pump light source and to control the power of the multi-mode pump light source; The external electrical signal modulation unit is used to receive an external electrical signal and control the power of the multi-mode pump light source based on the external electrical signal and its own electrical signal.

10. A multi-mode pump laser device, characterized in that: It comprises a multimode pump noise suppressor according to any one of claims 1 to 9, used for outputting a second optical signal.

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