Self-starting 9-shaped cavity laser and device based on motor disturbance

Abstract

The invention discloses a self-starting 9-shaped cavity laser and device based on motor disturbance, and relates to the technical field of lasers. The laser comprises a nonlinear amplification loop, a linear arm, a polarization maintaining optical fiber coupler and a motor disturbance module. And the polarization-maintaining optical fiber coupler is connected with the linear arm and the nonlinear amplification loop respectively. High-frequency mechanical vibration is applied to the polarization-maintaining passive optical fiber in the nonlinear amplification loop through the motor disturbance module, so that a high-strength initial noise signal is formed in the cavity, mode competition in the cavity is promoted, and noise is accelerated to enter a positive feedback area of the resonant cavity. Mode locking self-starting under the low pumping condition is achieved, pumping power waste is reduced, and the device cost is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of lasers, and in particular relates to a self-starting 9-shaped cavity laser and a device based on motor disturbance. Background Art

[0002] Mode locking technology is a key technology for ultrafast lasers to generate ultrashort pulses. Its basic principle is to introduce a specific phase relationship or nonlinear effect in the laser cavity so that the randomly fluctuating light signal oscillates back and forth multiple times in the cavity to form a stable ultrashort pulse sequence.

[0003] As a new type of mode-locking technology, the figure-9 cavity laser has gradually attracted attention in the fields of ultrafast laser processing, spectral detection, bio-optics, etc. due to its advantages of long life and high stability. The existing figure-9 cavity laser mode-locking generally requires a high pump current to achieve rapid self-starting, and after starting, it is in a multi-pulse state. The fundamental frequency single pulse state is obtained by gradually reducing the pump current, and this transition process from multi-pulses to single pulses may fail under unreasonable design; the start-up time of the figure-9 cavity will have a certain probability distribution, and the individual start-up time may be longer; this leads to the problems of pump waste, probabilistic distribution of start-up time, cumbersome optimization and adjustment, and limited optical path parameter space and pulse parameter space in the existing figure-9 cavity mode-locked laser. Summary of the invention

[0004] The purpose of the present invention is to solve the problems of pump waste, probabilistic distribution of start-up time, cumbersome optimization and adjustment, limited optical path parameter space and pulse parameter space in the existing 9-cavity mode-locked laser, and propose a self-starting 9-cavity laser and device based on motor disturbance.

[0005] In the first aspect of the implementation of the present invention, a self-starting 9-shaped cavity laser based on motor perturbation is first proposed, comprising a nonlinear amplification loop, a linear arm, a polarization-maintaining fiber coupler, and a control module. The nonlinear amplification loop comprises a motor perturbation module, a fiber fixing patch, and a polarization-maintaining passive fiber, wherein: The two optical fiber fixing stickers are used to fix the two ends of the polarization-maintaining passive optical fiber respectively, and the optical fiber of the polarization-maintaining passive optical fiber located between the optical fiber fixing stickers is used as a disturbance optical fiber, and a motor disturbance module is provided on one side of the disturbance optical fiber in the horizontal direction; The motor disturbance module is connected to the control module; the control module is used to receive the optical signal of the 2x2 polarization-maintaining fiber coupler and determine whether the optical signal is successfully locked. If not, a start instruction is sent to the motor disturbance module; the start instruction is used to control the motor disturbance module to tap the disturbance optical fiber to cause the disturbance optical fiber to vibrate mechanically at high frequency.

[0006] Preferably, the output module includes an output jumper head, a polarization-maintaining fiber isolator and a polarization-maintaining fiber grating; One end of the output jumper head is connected with a polarization-maintaining optical fiber isolator and a polarization-maintaining optical fiber grating in sequence.

[0007] Preferably, the control module comprises: a polarization-maintaining isolator, a photodetector, a main control board and a driving module; The control module is composed of a polarization-maintaining isolator, a photodetector, a main control board and a driving module, and the control module is respectively connected to a 2x2 polarization-maintaining fiber coupler, a motor disturbance module and a polarization-maintaining wavelength division multiplexer; The photoelectric detector is used to convert the optical signal in the 9-shaped cavity laser into an electrical signal, and send the electrical signal to the main control board and the driving module; The main control board and the driving module are used to obtain the electrical signal and determine whether the mode is locked. If the mode is locked, a start instruction is sent to the motor disturbance module. The main control board and the driving module are also used to load a preset program and inject pump light into the polarization-maintaining wavelength division multiplexer, so that the polarization-maintaining wavelength division multiplexer optically couples the pump light into the polarization-maintaining active optical fiber.

[0008] Preferably, the nonlinear amplification loop further includes: a motor disturbance module, an optical fiber fixing patch, a polarization-maintaining passive optical fiber, a polarization-maintaining active optical fiber, a polarization-maintaining wavelength division multiplexer and a phase shifter; A polarization-maintaining wavelength division multiplexer and a phase shifter are respectively arranged at one end of the 2x2 polarization-maintaining fiber coupler away from the output module, a polarization-maintaining active fiber is connected between the 2x2 polarization-maintaining fiber coupler and the polarization-maintaining wavelength division multiplexer, a polarization-maintaining passive fiber is connected between the 2x2 polarization-maintaining fiber coupler and the phase shifter, and an optical fiber is connected between the polarization-maintaining wavelength division multiplexer and the phase shifter.

[0009] Preferably, the control module is connected to a 2x2 polarization-maintaining fiber coupler and a polarization-maintaining wavelength division multiplexer, respectively.

[0010] Preferably, the motor disturbance module consists of a slapping handle and a motor, and the motor output end is connected to the slapping handle. The motor disturbance module is used to receive the start-up instruction and load the preset motor voltage and motor working time according to the start-up instruction.

[0011] Preferably, the 9-shaped cavity laser further includes a pump source, and the pump source includes a 14-pin butterfly laser with a wavelength of 980 nm.

[0012] Preferably, the splitting ratio of the 2x2 polarization-maintaining fiber coupler is 40 / 60.

[0013] Beneficial effects of the present invention: 1) The motor of the present invention is powered on and rotates, driving the striking handle to continuously strike the polarization-maintaining passive optical fiber. Since the optical fiber is elastic and is fixed by the optical fiber fixing sticker, the polarization-maintaining passive optical fiber is in a state of high-frequency vibration under the striking of the striking handle, and can introduce a noise signal of sufficient intensity when the laser is powered on, thereby accelerating the locking mode.

[0014] 2) The present invention introduces a noise signal of a certain intensity by tapping the tapping handle, thereby achieving mode-locking self-starting under low pump current, reducing pump power waste and lowering device cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention will be further described below in conjunction with the accompanying drawings.

[0016] Figure 1 A schematic diagram of the structure of a self-starting 9-shaped cavity laser based on motor disturbance provided in an embodiment of the present invention; Figure 2 A schematic diagram of a motor disturbance module of another self-starting 9-shaped cavity laser based on motor disturbance provided in an embodiment of the present invention; Figure 3 A schematic diagram of a slap handle of a self-starting 9-shaped cavity laser based on motor disturbance provided in an embodiment of the present invention; Figure 4 A startup comparison diagram of a self-starting 9-shaped cavity laser based on motor disturbance provided in an embodiment of the present invention.

[0017] In the figure: 100, nonlinear amplification loop; 101, linear arm; 102, motor disturbance module; 103, control module; 104, fiber fixing sticker; 105, polarization-maintaining passive fiber; 106, 2x2 polarization-maintaining fiber coupler; 107, polarization-maintaining active fiber; 108, polarization-maintaining wavelength division multiplexer; 109, optical fiber; 1010, phase shifter; 1011, output jumper head; 1012, polarization-maintaining fiber isolator; 1013, polarization-maintaining fiber grating; 1021, striking handle; 1022, motor; 1031, polarization-maintaining isolator; 1032, photodetector; 1033, main control board and drive module. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The term "and / or" herein is only a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, A and B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the present invention, the description of "first", "second", etc. is only used for descriptive purposes, and cannot be understood as indicating or implying its relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" can explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in the field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0019] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative work shall fall within the scope of protection of the present invention.

[0020] The embodiment of the present invention provides a self-starting 9-shaped cavity laser based on motor disturbance. Figure 1-3 , Figure 1 A schematic diagram of the structure of a self-starting 9-shaped cavity laser based on motor disturbance provided by an embodiment of the present invention. The 9-shaped cavity laser nonlinear amplification loop 100, linear arm 101, polarization-maintaining fiber coupler 106, control module 103, nonlinear amplification loop 100 includes a motor disturbance module 102, fiber fixing sticker 104 and polarization-maintaining passive fiber 105, wherein: The two optical fiber fixing stickers 104 are used to fix the two ends of the polarization-maintaining passive optical fiber 105 respectively, and the optical fiber of the polarization-maintaining passive optical fiber 105 located between the optical fiber fixing stickers 104 is used as a disturbance optical fiber, and a motor disturbance module 102 is provided on one side of the disturbance optical fiber in the horizontal direction; The motor disturbance module 102 is connected to the control module 103; the control module 103 is used to receive the optical signal of the 2x2 polarization-maintaining fiber coupler 106 and determine whether the optical signal is successfully locked. If not, a start instruction is sent to the motor disturbance module; the start instruction is used to control the motor disturbance module 102 to tap the disturbance optical fiber to make the disturbance optical fiber vibrate at high frequency.

[0021] In one implementation, the main control board and the driving module 1033 are powered on to drive the pump source and the motor disturbance module 102. The motor disturbance module 102 is loaded with a preset motor voltage and a motor working time. The pump source injects pump light into the polarization-maintaining wavelength division multiplexer 108. The polarization-maintaining wavelength division multiplexer 108 receives the pump light and propagates it in the direction of the polarization-maintaining active optical fiber 107. The pump light propagates to the polarization-maintaining active optical fiber 107, and the polarization-maintaining active optical fiber 107 absorbs and emits continuous signal light. The signal light is transmitted clockwise and counterclockwise in the loop, and a nonlinear phase shift is generated under the action of the asymmetry of the positions of the phase shifter 1010 and the polarization-maintaining active optical fiber 107. When the two optical signals reach the 2x2 polarization-maintaining fiber coupler 106, they interfere with each other and propagate to the polarization-maintaining fiber grating 1013. The polarization-maintaining fiber grating 1013 reflects a part of the optical signal and propagates to the 2x2 polarization-maintaining fiber coupler 106. After passing through the 2x2 polarization-maintaining fiber coupler 106, the optical signals are split into two optical signals again. The optical signals propagate clockwise and counterclockwise in the 2x2 polarization-maintaining fiber coupler 106-polarization-maintaining wavelength division multiplexer 108-phase shifter 1010-2x2 polarization-maintaining fiber coupler 106 respectively, and are split into two optical signals. One optical signal passes through the polarization-maintaining fiber grating 1013-polarization-maintaining fiber isolator 1012-output jumper head 1011 outputs, and another beam of light passes through the polarization-maintaining isolator 1031-photodetector 1032-main control board and drive module 1033 for mode locking judgment. The photodetector 1032 converts the optical signal into an electrical signal, and the main control board and drive module 1033 judge whether the mode is locked according to the electrical signal. If it fails, the motor disturbance module 102 reloads the preset motor voltage and motor working time, and the motor 1022 in the motor disturbance module drives the clapping handle 1021 to continuously clap the polarization-maintaining passive optical fiber 105 until the mode is successfully locked.

[0022] In one implementation, the 2x2 polarization-maintaining fiber coupler 106 and the polarization-maintaining wavelength division multiplexer 108 are connected through the polarization-maintaining active fiber 107, and the 2x2 polarization-maintaining fiber coupler 106 and the phase shifter 1010 are connected through the polarization-maintaining passive fiber 105. The polarization-maintaining passive fiber 105 is fixed to the laser housing through two fiber fixing stickers 104. The polarization-maintaining passive fiber 105 between the two fiber fixing stickers 104 is 20 mm higher than the laser housing. The motor 1022 drives the slapping handle 1021 so that the slapping handle 1021 continuously rotates to slap the polarization-maintaining passive fiber 105. The length of the slapping handle 1021 is 20 mm, and the rotation speed of the motor 1022 is: DC=3V, 15200RPM; DC=6V, 28000RPM. That is, when the DC voltage is 3V, the rotation speed of the motor is 15200RPM. When the DC voltage is 6V, the rotation speed of the motor is 28000RPM.

[0023] In one implementation, the linear arm 101 is connected to the 2x2 polarization-maintaining fiber coupler 106, the control module 103 is respectively connected to the 2x2 polarization-maintaining fiber coupler 106 and the polarization-maintaining wavelength division multiplexer 108 through an optical path, and the control module 103 is connected to the motor 1022 in the motor disturbance module 102 through a circuit.

[0024] In one implementation, the 2x2 polarization-maintaining fiber coupler 106 and the polarization-maintaining wavelength division multiplexer 108 are connected via a polarization-maintaining active optical fiber 107, the polarization-maintaining wavelength division multiplexer 108 and the phase shifter 1010 are connected via an optical fiber 109, the 2x2 polarization-maintaining fiber coupler 106 and the phase shifter 1010 are connected via a polarization-maintaining passive optical fiber 105, the polarization-maintaining passive optical fiber 105 is fixed via two optical fiber fixing stickers 104, and a motor disturbance module 102 is provided on one side of the horizontal direction of the polarization-maintaining passive optical fiber 105 located between the two optical fiber fixing stickers 104.

[0025] In one implementation, for example, if there is no motor perturbation module 102 to perturb the optical fiber, a high pump current must be applied to achieve self-starting. At this time, the internal optical signal is in a multi-pulse state, and the pump current needs to be gradually reduced to obtain a baseband single pulse state. The motor perturbation module 102 can introduce additional noise intensity to the laser under low pump current, thereby accelerating the evolution of the baseband single pulse and achieving rapid self-starting.

[0026] In one implementation, Figure 4 A startup comparison diagram of a self-starting 9-shaped cavity laser based on motor disturbance provided by an embodiment of the present invention; the startup effect finally achieved is as follows Figure 4 As shown, the characteristic of the traditional 9-shaped cavity that fast self-starting requires the application of high pump current is avoided, and the locked mode self-starting is achieved under low pump current, which reduces the waste of pump power, reduces the device cost, and simplifies the optimization process of the 9-shaped cavity.

[0027] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A self-starting 9-shaped cavity laser based on motor disturbance, characterized in that: It comprises a nonlinear amplification loop (100), a linear arm (101), a polarization-maintaining optical fiber coupler (106), and a control module (103); the nonlinear amplification loop (100) comprises a motor disturbance module (102), an optical fiber fixing patch (104), and a polarization-maintaining passive optical fiber (105), wherein: Two optical fiber fixing stickers (104) are used to fix two ends of a polarization-maintaining passive optical fiber (105) respectively, and the polarization-maintaining passive optical fiber (105) is used as a disturbance optical fiber, and a motor disturbance module (102) is provided on one side of the disturbance optical fiber in the horizontal direction; The motor disturbance module (102) is connected to a control module (103); the control module (103) is used to receive an optical signal from a 2x2 polarization-maintaining optical fiber coupler (106) and determine whether the optical signal is successfully mode-locked, and if not, to send a start instruction to the motor disturbance module; the start instruction is used to control the motor disturbance module (102) to strike the disturbance optical fiber, so as to cause the disturbance optical fiber to vibrate mechanically at high frequency.

2. A self-starting 9-shaped cavity laser based on motor disturbance according to claim 1, characterized in that: The linear arm (101) comprises an output jumper head (1011), a polarization-maintaining optical fiber isolator (1012) and a polarization-maintaining optical fiber grating (1013); One end of the output jumper head (1011) is connected in sequence to a polarization-maintaining optical fiber isolator (1012) and a polarization-maintaining optical fiber grating (1013).

3. A self-starting 9-shaped cavity laser based on motor disturbance according to claim 1, characterized in that: The control module (103) comprises: a polarization-maintaining isolator (1031), a photodetector (1032), and a main control board and a driving module (1033); The control module (103) is composed of a polarization-maintaining isolator (1031), a photodetector (1032), a main control board and a driving module (1033); the control module (103) is respectively connected to a 2x2 polarization-maintaining optical fiber coupler (106), a motor disturbance module (102) and a polarization-maintaining wavelength division multiplexer (108); The photoelectric detector (1032) is used to convert the optical signal in the 9-shaped cavity laser into an electrical signal, and send the electrical signal to the main control board and the driving module (1033); The main control board and the driving module (1033) are used to obtain the electrical signal and determine whether the mode is locked; The main control board and the driving module (1033) contain a 980nm band pump source, which injects pump light into the polarization-maintaining wavelength division multiplexer (108).

4. A self-starting 9-shaped cavity laser based on motor disturbance according to claim 1, characterized in that: The nonlinear amplification loop (100) further comprises: an optical fiber fixing patch (104), a polarization-maintaining passive optical fiber (105), a polarization-maintaining active optical fiber (107), a polarization-maintaining wavelength division multiplexer (108), an optical fiber (109), and a phase shifter (1010); A polarization-maintaining wavelength division multiplexer (108) and a phase shifter (1010) are respectively arranged at one end of the 2x2 polarization-maintaining optical fiber coupler (106) away from the linear arm (101); a polarization-maintaining active optical fiber (107) is connected between the 2x2 polarization-maintaining optical fiber coupler (106) and the polarization-maintaining wavelength division multiplexer (108); a polarization-maintaining passive optical fiber (105) is connected between the 2x2 polarization-maintaining optical fiber coupler (106) and the phase shifter (1010); and an optical fiber (109) is connected between the polarization-maintaining wavelength division multiplexer (108) and the phase shifter (1010).

5. The self-starting 9-shaped cavity laser based on motor disturbance according to claim 1 is characterized in that: The control module (103) is respectively connected to a 2x2 polarization-maintaining optical fiber coupler (106) and a polarization-maintaining wavelength division multiplexer (108).

6. A self-starting 9-shaped cavity laser based on motor disturbance according to claim 1, characterized in that: The motor disturbance module (102) is composed of a slapping handle (1021) and a motor (1022); an output end of the motor (1022) is connected to the slapping handle (1021); and the motor disturbance module (102) is used to receive the start instruction and load a preset motor voltage and motor working time according to the start instruction.

7. The self-starting 9-shaped cavity laser based on motor disturbance according to claim 1 is characterized in that The 9-shaped cavity laser also includes a pump source, which includes a 14-pin butterfly laser with a wavelength of 980 nm.

8. The self-starting 9-shaped cavity laser based on motor disturbance according to claim 1 is characterized in that The splitting ratio of the 2x2 polarization-maintaining fiber coupler (106) is 40 / 60.

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