CN111600180A - Femtosecond fiber laser with frequency adjustable according to scanning path and working method thereof - Google Patents

Femtosecond fiber laser with frequency adjustable according to scanning path and working method thereof Download PDF

Info

Publication number
CN111600180A
CN111600180A CN202010524571.0A CN202010524571A CN111600180A CN 111600180 A CN111600180 A CN 111600180A CN 202010524571 A CN202010524571 A CN 202010524571A CN 111600180 A CN111600180 A CN 111600180A
Authority
CN
China
Prior art keywords
femtosecond
laser beam
pulse laser
frequency
fiber
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202010524571.0A
Other languages
Chinese (zh)
Inventor
周辉
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ji Hua Laboratory
Original Assignee
Ji Hua Laboratory
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ji Hua Laboratory filed Critical Ji Hua Laboratory
Priority to CN202010524571.0A priority Critical patent/CN111600180A/en
Publication of CN111600180A publication Critical patent/CN111600180A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
    • H01S3/06—Construction or shape of active medium
    • H01S3/063—Waveguide lasers, i.e. whereby the dimensions of the waveguide are of the order of the light wavelength
    • H01S3/067—Fibre lasers
    • H01S3/06708—Constructional details of the fibre, e.g. compositions, cross-section, shape or tapering
    • H01S3/06716—Fibre compositions or doping with active elements
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/005—Optical devices external to the laser cavity, specially adapted for lasers, e.g. for homogenisation of the beam or for manipulating laser pulses, e.g. pulse shaping
    • H01S3/0085—Modulating the output, i.e. the laser beam is modulated outside the laser cavity
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
    • H01S3/06—Construction or shape of active medium
    • H01S3/063—Waveguide lasers, i.e. whereby the dimensions of the waveguide are of the order of the light wavelength
    • H01S3/067—Fibre lasers
    • H01S3/0675—Resonators including a grating structure, e.g. distributed Bragg reflectors [DBR] or distributed feedback [DFB] fibre lasers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
    • H01S3/08—Construction or shape of optical resonators or components thereof
    • H01S3/08013—Resonator comprising a fibre, e.g. for modifying dispersion or repetition rate
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
    • H01S3/08—Construction or shape of optical resonators or components thereof
    • H01S3/08018—Mode suppression
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
    • H01S3/10007—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating in optical amplifiers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
    • H01S3/11—Mode locking; Q-switching; Other giant-pulse techniques, e.g. cavity dumping
    • H01S3/1106—Mode locking
    • H01S3/1109—Active mode locking

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Optics & Photonics (AREA)
  • Lasers (AREA)

Abstract

The femtosecond fiber laser with the adjustable frequency according to the scanning path comprises a self-mode-locking fiber oscillator, a first Bragg grating, an amplifying unit, a second Bragg grating, a laser galvanometer scanning unit, a control unit and a data analysis processing unit, wherein the first Bragg grating and the second Bragg grating form a resonator.

Description

Femtosecond fiber laser with frequency adjustable according to scanning path and working method thereof
Technical Field
The invention relates to the technical field of medical instruments, in particular to a femtosecond fiber laser with adjustable frequency according to a scanning path and a working method thereof.
Background
The effect of the laser pulses is a highly non-linear function of its parameters within the eye tissue, including the anterior ocular segment region, the mid-ocular segment region, the posterior ocular segment region, and so forth. Thus, lasers with the same energy/pulse but different pulse durations may have different results during surgery, requiring accurate determination of data information for each point of the eye tissue, timely feedback to the control unit, adjustment of the laser pulse energy at each point of the eye tissue, and mitigation of surgical problems associated with the information about changes in the shape of the eye tissue before and during surgery. Different eye tissues need lasers with different energy, namely, different frequencies, and the problem of urgent need to be solved is to rapidly and accurately perform surgery by obtaining the lasers with the required frequencies through data analysis and processing according to image information of the different eye tissues. Meanwhile, the over-high laser pulse energy can cause the over-high temperature of the circuit, easily burn out the gain optical fiber and even burn out all optical path devices, and the problem of circuit safety caused by the over-high laser pulse energy is urgently needed to be solved.
Disclosure of Invention
Therefore, it is necessary to provide a femtosecond laser capable of adjusting the frequency of the pulse laser beam according to the image information to achieve all-fiber femtosecond laser outputs with different energy requirements, in order to overcome the drawbacks of the prior art.
In order to achieve the purpose, the invention adopts the following technical scheme:
a frequency is according to the femtosecond fiber laser that the scanning path is adjustable, the self-mode-locked fiber oscillator, the first Bragg grating, the amplification unit, the second Bragg grating, the laser galvanometer scanning unit, the control unit and the data analysis processing unit, the first Bragg grating and the second Bragg grating form the resonator; wherein:
the femtosecond seed pulse laser beam output by the self-mode-locked fiber oscillator enters the first Bragg grating through a fiber transmission line, the femtosecond seed pulse laser beam forms a second femtosecond pulse laser beam in the resonator, the resonator expands the duration of the second femtosecond pulse laser beam and outputs the second femtosecond pulse laser beam to the amplifying unit, the amplifying unit receives the second femtosecond pulse laser beam and amplifies the second femtosecond pulse laser beam to form a third femtosecond pulse laser beam, and the third femtosecond pulse laser beam returns to the first Bragg grating, is compressed by the first Bragg grating for the duration and is output;
the compressed third femtosecond pulse laser beam is focused in the target area by the laser galvanometer scanning unit through an optical fiber transmission line, the laser galvanometer scanning unit scans the target area information in real time in a three-dimensional mode through a variable scanning path and transmits the information to the data analysis processing unit for analysis processing of the scanning path, and the control unit scans the path information in real time to adjust the frequency of the self-mode-locking optical fiber oscillator and generates and outputs a frequency femtosecond pulse laser beam.
In some of the embodiments, the amplifying unit comprises a polarization isolator, a polarizer, a side-pumped amplifier and a dispersion compensator which are sequentially fusion spliced through an active fiber, the polarization isolator is configured to receive the first bragg grating stretched femtosecond seed pulsed laser beam, the polarizer receives the stretched femtosecond seed pulse laser beam and directs the stretched femtosecond seed pulse laser beam toward the side-pumped amplifier, the side pumping amplifier amplifies the gain-stretched femtosecond seed pulse laser beam and outputs the femtosecond seed pulse laser beam to the dispersion compensator, the dispersion compensator is for reducing the dispersion of the amplified stretched femtosecond seed pulsed laser beam, the polarization isolator is also used for receiving the femtosecond seed pulse laser beam amplified by the side-pumped amplifier and outputting the femtosecond seed pulse laser beam to the first Bragg grating.
In some of these embodiments, the active fibers are doped with gain ions.
In some of these embodiments, the gain ion is one or more of neodymium, ytterbium, erbium, thulium, holmium, dysprosium, or praseodymium.
In some of these embodiments, the active fiber core diameter is 6.2 and the mode field diameter is 8.8 μm to 9.2 μm.
In some of these embodiments, the reflectivity of the first bragg grating is equal to or higher than the reflectivity of the second bragg grating.
In some embodiments, the optical fiber transmission line is a single-mode field photonic crystal fiber with a length of 10-20 cm and a mode field diameter of 4.8 μm.
In some of these embodiments, the femtosecond seed pulsed laser beam has a wavelength of 1030nm ± 5nm, a pulse width of less than 500fs, a pulse frequency of 120kHz, a pulse energy of 10-40 μ J, a beam diameter of 3 ± 1 μ M, a beam mass M2<1.2, a pulse energy stability < 2% RMS, an average power of 2.5W, and a peak power of >40 MW.
In some of these embodiments, the laser galvanometer scanning unit scans the target area along a minimum acceleration path.
In some of these embodiments, the laser galvanometer scanning unit scans the target area along a path, and the control unit adjusts the laser frequency of the self-mode-locked fiber oscillator when approaching a retraced portion of the path; or the laser galvanometer scanning unit scans the target area in XYZ three-dimensional directions, and the control unit adjusts the laser frequency of the self-mode-locked fiber oscillator when the target area is close to the path turning part; or the laser galvanometer scanning unit carries out spiral scanning on the target area, and the control unit adjusts the laser frequency of the self-mode-locked fiber oscillator when the scanning is close to the spiral central part; or the laser galvanometer scanning unit carries out linear scanning on the target area, and the control unit adjusts the laser frequency of the self-mode-locked optical fiber oscillator when the laser galvanometer scanning unit is close to a linear end point or a retraced part.
In addition, the invention also provides a working method of the femtosecond fiber laser with the frequency adjustable according to the scanning path, which comprises the following steps:
the femtosecond seed pulse laser beam output by the self-mode-locked fiber oscillator enters the first Bragg grating through a fiber transmission line;
the femtosecond seed pulse laser beam forms a second femtosecond pulse laser beam in the resonator, and the resonator widens the duration of the second femtosecond pulse laser beam and outputs the second femtosecond pulse laser beam to the amplifying unit;
the amplifying unit receives the second femtosecond pulse laser and amplifies the amplitude of the second femtosecond pulse laser to form a third femtosecond pulse laser beam, and the third femtosecond pulse laser beam returns to the first Bragg grating, is compressed for duration by the first Bragg grating and is output;
the compressed third femtosecond pulse laser beam is focused in the target area by the laser galvanometer scanning unit through an optical fiber transmission line, the laser galvanometer scanning unit scans the target area information in real time in a three-dimensional mode through a variable scanning path and transmits the information to the data analysis processing unit for analysis processing of the scanning path, and the control unit scans the path information in real time to adjust the frequency of the self-mode-locking optical fiber oscillator and generates and outputs a frequency femtosecond pulse laser beam.
In some of these embodiments, the following steps are also included:
when the laser is focused on a second target area, the steps are repeated, and the control unit adjusts the frequency of the self-mode-locked fiber oscillator according to the real-time image information of the second target area, generates and outputs a second frequency femtosecond pulse laser beam.
In some of these embodiments, the following steps are also included:
and when the laser is focused on a third target area, repeating the steps, and adjusting the frequency of the self-mode-locked fiber oscillator by the control unit according to the real-time image information of the third target area to generate and output a third frequency femtosecond pulse laser beam.
In some of these embodiments, the first target region is a corneal region, the second target region is at least one of a lens and a cataract region, the third target region is at least one of a retinal and maculopathy deformed region, the first frequency femtosecond pulsed laser beam has a frequency of 50 to 100kHz, the second frequency femtosecond pulsed laser beam has a frequency of 100 to 200kHz, and the third frequency femtosecond pulsed laser beam has a frequency of 50 to 100 kHz.
The invention adopts the technical scheme that the method has the advantages that:
according to the femtosecond fiber laser with the frequency adjustable according to the scanning path, a femtosecond seed pulse laser beam output by a self-mode-locked fiber oscillator enters a first Bragg grating through a fiber transmission line, the femtosecond seed pulse laser beam forms a second femtosecond pulse laser beam in a resonator, the resonator widens the duration time of the second femtosecond pulse laser and outputs the second femtosecond pulse laser beam to an amplifying unit, the amplifying unit receives the second femtosecond pulse laser beam and amplifies the amplitude of the second femtosecond pulse laser beam to form a third femtosecond pulse laser beam, and the third femtosecond pulse laser beam returns to the first Bragg grating, is compressed by the first Bragg grating for the duration time and is output; the compressed third femtosecond pulse laser beam is focused in a target area by the laser galvanometer scanning unit through an optical fiber transmission line, the laser galvanometer scanning unit scans target area information in real time in a three-dimensional mode through a variable scanning path and transmits the target area information to the data analysis processing unit for analysis processing of the scanning path, the control unit scans the path information in real time to adjust the frequency of the self-mode-locking optical fiber oscillator and generates and outputs a frequency femtosecond pulse laser beam.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
Fig. 1 is a schematic structural diagram of a femtosecond fiber laser with adjustable frequency according to a scanning path, provided by the invention.
Fig. 2 is a schematic structural diagram of an amplifying unit provided by the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
Referring to fig. 1, a schematic structural diagram of a femtosecond fiber laser with a frequency adjustable according to a scanning path according to the present invention includes: the self-mode-locked fiber oscillator comprises a self-mode-locked fiber oscillator 110, a first Bragg grating 120, an amplifying unit 130, a second Bragg grating 140, a laser galvanometer scanning unit 150, a control unit 160 and a data analysis processing unit 170, wherein the first Bragg grating 120 and the second Bragg grating 140 form a resonator 121.
The working principle of the femtosecond fiber laser with the frequency adjustable according to the scanning path is as follows:
the femtosecond seed pulse laser beam output by the self-mode-locked fiber oscillator 110 enters the first bragg grating 120 through a fiber transmission line, the femtosecond seed pulse laser beam forms a second femtosecond pulse laser beam in the resonator 121, the resonator 121 widens the duration of the second femtosecond pulse laser beam and outputs the second femtosecond pulse laser beam to the amplifying unit 130, the amplifying unit 130 receives the second femtosecond pulse laser beam and amplifies the second femtosecond pulse laser beam to form a third femtosecond pulse laser beam, and the third femtosecond pulse laser beam returns to the first bragg grating 120, is compressed by the first bragg grating 120 for the duration and is output.
The compressed third femtosecond pulse laser beam is focused in the target area by the laser galvanometer scanning unit 150 through an optical fiber transmission line, the laser galvanometer scanning unit 150 scans the target area information in real time in a three-dimensional manner by a variable scanning path and transmits the information to the data analysis processing unit 170 for analysis processing of the scanning path, and the control unit 160 scans the path information in real time to adjust the frequency of the self-mode-locked optical fiber oscillator 110 and generate and output a frequency femtosecond pulse laser beam.
It can be understood that the frequency of the femtosecond pulse laser beam output by the femtosecond fiber laser device with the adjustable frequency according to the scanning path can be also output by the femtosecond pulse laser beam with the second frequency and/or the femtosecond pulse laser beam with the third frequency by utilizing the optical path structure, and the output laser pulse duration is less than 500fs for the frequency of the femtosecond pulse laser beam, the femtosecond pulse laser beam with the second frequency and the femtosecond pulse laser beam with the third frequency.
Referring to fig. 2, which is a schematic structural diagram of an amplifying unit according to an embodiment of the present invention, the amplifying unit 130 includes a polarization isolator 131, a polarizer 132, a side pump amplifier 133, and a dispersion compensator 134 that are sequentially fusion spliced by an active fiber, the polarization isolator 131 is configured to receive the femtosecond seed pulse laser beam broadened by the first bragg grating 120, the polarizer 132 receives the broadened femtosecond seed pulse laser beam and directs the broadened femtosecond seed pulse laser beam toward the side pump amplifier 133, the side pump amplifier 133 amplifies the gain broadened femtosecond seed pulse laser beam and outputs the femtosecond seed pulse laser beam to the dispersion compensator 134, the dispersion compensator 134 is configured to reduce dispersion of the amplified broadened femtosecond seed pulse laser beam, and the polarization isolator 131 is further configured to receive the femtosecond seed pulse laser beam amplified by the side pump amplifier 133 and output the femtosecond seed pulse laser beam to the dispersion compensator 134 The first bragg grating 120 outputs, thereby realizing the amplification of pulse power, improving the average power of pulse laser output by the femtosecond pulse laser, reducing dispersion and improving the beam quality.
It can be understood that the present invention adopts the amplifying unit 130 composed of the polarization isolator 131, the polarizer 132, the side pump amplifier 133 and the dispersion compensator 134 which are sequentially fused and spliced by the active fiber 135 through the seed/pump fiber coupler, and forms high power density in the fiber by the action of the external pump light, outputs laser from the fiber core, and performs high gain and distortion-free amplification on the seed femtosecond pulse.
Further, the femtosecond fiber oscillator 110 and the side pump amplifier 133 are combined to integrate the comprehensive characteristics of the fiber laser and the all-solid-state laser, so that the laser has the characteristics of compact structure, high stability, high single-pulse energy and the like.
In some of the embodiments, the active optical fibers 135 are doped with gain ions, the gain ions are one or more of neodymium, ytterbium, erbium, thulium, holmium, dysprosium, or praseodymium, the core diameter of the active optical fibers 135 is 6.2 ± 0.5 μm, and the mode field diameter is 9.2 ± 0.5 μm; the active fiber 135 generates a new light wave or amplified optical signal, enabling a series of laser outputs in narrow linewidth, single frequency, continuous or pulsed lasers.
It can be understood that the combination of the active fiber and the first bragg grating 120 and/or the second bragg grating 140 can function as a sensor, and can measure temperature and tension simultaneously, once the temperature of the sensor is too high, the stronger laser self-generated oscillation generated in the power amplifier stage can be automatically transmitted to the control system to disconnect the whole optical path system, so that the gain fiber cannot be burnt out, all optical path devices cannot be burnt out, and the safety of the whole femtosecond laser is improved.
In some of these embodiments, the reflectivity of the first bragg grating 120 is equal to or higher than the reflectivity of the second bragg grating 140.
It is understood that the resonator formed by the first bragg grating 120 and the second bragg grating 140 can receive, circulate and amplify the femtosecond seed laser beam, and the pump light becomes the seed laser in the active fiber and the resonator.
In some embodiments, the optical fiber transmission line is a single-mode field photonic crystal fiber, the length of the single-mode field photonic crystal fiber is 10-20 cm, and the diameter of a mode field is 4.8 μm; and the single-mode-field photonic crystal fiber is adopted, so that the adjustment difficulty of the femtosecond pulse laser can be effectively reduced, the structure of the femtosecond pulse laser is simplified, the volume of the laser is reduced, the use of space optical devices is reduced, and the long-term stability of the femtosecond pulse laser is improved.
In some of these embodiments, the femtosecond seed pulsed laser beam has a wavelength of 1030nm ± 5nm, a pulse width of less than 500fs, a pulse frequency of 120kHz, a pulse energy of 10-40 μ J, a beam diameter of 3 ± 1 μ M, a beam mass M2<1.2, a pulse energy stability < 2% RMS, an average power of 2.5W, and a peak power of >40 MW.
It is understood that the above parameters can be adjusted according to actual needs.
In some of these embodiments, the laser galvanometer scanning unit 150 scans the target area along a path of minimum acceleration.
Specifically, the laser galvanometer scanning unit 150 scans the target area along the zigzag path, and the control unit 160 adjusts the laser frequency of the self-mode-locked fiber oscillator 110 when approaching the retraced portion of the path; or the laser galvanometer scanning unit 150 scans the target area in XYZ three-dimensional directions, and the control unit 160 adjusts the laser frequency of the self-mode-locked fiber oscillator 110 when approaching a path retracing part; or the laser galvanometer scanning unit 150 performs a helical scan of the target area, and the control unit 160 adjusts the laser frequency of the self-mode-locked fiber oscillator 110 when the scan is close to the helical center portion; or the laser galvanometer scanning unit 150 performs linear scanning on the target area, and the control unit 160 adjusts the laser frequency of the self-mode-locked fiber oscillator 110 when approaching a linear end point or a retraced portion.
The femtosecond fiber laser with the adjustable laser frequency according to the scanning path provided by the embodiment of the invention can adjust the frequency of the pulse laser beam according to the scanning path, realize the output of all-fiber femtosecond lasers with different energy requirements, and simultaneously ensure the structural compactness and the circuit safety of the device.
Example 2
The invention also provides an operating method of the femtosecond fiber laser with the frequency adjustable according to the scanning path, which is described in embodiment 1, and the operating method comprises the following steps:
step S110: the femtosecond seed pulse laser beam output from the self-mode-locked fiber oscillator 110 enters the first bragg grating 120 through a fiber transmission line.
Step S120: the femtosecond seed pulse laser beam forms a second femtosecond pulse laser beam in the resonator 121, and the resonator 121 widens the duration of the second femtosecond pulse laser beam and outputs the same to the amplifying unit 130.
Step S130: the amplifying unit 130 receives the second femtosecond pulse laser and performs amplitude amplification to form a third femtosecond pulse laser beam, and the third femtosecond pulse laser beam returns to the first bragg grating 120, is compressed by the first bragg grating 120 for a duration, and is output.
Step S140: the compressed third femtosecond pulse laser beam is focused in the target area by the laser galvanometer scanning unit 150 through an optical fiber transmission line, the laser galvanometer scanning unit 150 scans the target area information in real time in a three-dimensional manner by a variable scanning path and transmits the information to the data analysis processing unit 170 for analysis processing of the scanning path, and the control unit 160 scans the path information in real time to adjust the frequency of the self-mode-locked optical fiber oscillator 110 and generate and output a frequency femtosecond pulse laser beam.
In some of these embodiments, the following steps are also included:
step S150: when the eye region is focused on the second target region, the above steps are repeated, and the control unit 160 adjusts the frequency of the self-mode-locked fiber oscillator 110 according to the real-time image information of the second target region, generates and outputs a second frequency femtosecond pulse laser beam, so as to perform an operation on the corresponding eye region.
In some of these embodiments, the following steps are also included:
step S160: when the eye region is focused on the third target region, the above steps are repeated, and the control unit 160 adjusts the frequency of the self-mode-locked fiber oscillator 110 according to the real-time image information of the third target region, and generates and outputs a third frequency femtosecond pulse laser beam to perform an operation on the corresponding eye region.
In some of these embodiments, the first target region is a corneal region, the second target region is at least one of a lens and a cataract region, the third target region is at least one of a retinal and maculopathy deformed region, the first frequency femtosecond pulsed laser beam has a frequency of 50 to 100kHz, the second frequency femtosecond pulsed laser beam has a frequency of 100 to 200kHz, and the third frequency femtosecond pulsed laser beam has a frequency of 50 to 100 kHz.
The femtosecond fiber laser with the adjustable laser frequency according to the scanning path provided by the embodiment of the invention can adjust the frequency of the pulse laser beam according to the scanning path, realize the output of all-fiber femtosecond lasers with different energy requirements, and simultaneously ensure the structural compactness and the circuit safety of the device.
Of course, the frequency of the femtosecond fiber laser adjustable according to the scanning path can be changed and modified in various ways, and is not limited to the specific structure of the above embodiment. In conclusion, the scope of the present invention should include those changes or substitutions and modifications which are obvious to those of ordinary skill in the art.

Claims (14)

1. A femtosecond fiber laser with adjustable frequency according to a scanning path, comprising: the self-mode-locking optical fiber oscillator comprises a self-mode-locking optical fiber oscillator, a first Bragg grating, an amplifying unit, a second Bragg grating, a laser galvanometer scanning unit, a control unit and a data analysis processing unit, wherein the first Bragg grating and the second Bragg grating form a resonator; wherein:
the femtosecond seed pulse laser beam output by the self-mode-locked fiber oscillator enters the first Bragg grating through a fiber transmission line, the femtosecond seed pulse laser beam forms a second femtosecond pulse laser beam in the resonator, the resonator expands the duration of the second femtosecond pulse laser beam and outputs the second femtosecond pulse laser beam to the amplifying unit, the amplifying unit receives the second femtosecond pulse laser beam and amplifies the second femtosecond pulse laser beam to form a third femtosecond pulse laser beam, and the third femtosecond pulse laser beam returns to the first Bragg grating, is compressed by the first Bragg grating for the duration and is output;
the compressed third femtosecond pulse laser beam is focused in the target area by the laser galvanometer scanning unit through an optical fiber transmission line, the laser galvanometer scanning unit scans the target area information in real time in a three-dimensional mode through a variable scanning path and transmits the information to the data analysis processing unit for analysis processing of the scanning path, and the control unit scans the path information in real time to adjust the frequency of the self-mode-locking optical fiber oscillator and generates and outputs a frequency femtosecond pulse laser beam.
2. The femtosecond fiber laser with adjustable frequency according to a scan path as set forth in claim 1, wherein the amplifying unit includes a polarization isolator, a polarizer, a side-pumped amplifier and a dispersion compensator, which are sequentially fusion-spliced by an active fiber, the polarization isolator is configured to receive the first bragg-grating-stretched femtosecond seed pulse laser beam, the polarizer receives the stretched femtosecond seed pulse laser beam and directs the stretched femtosecond seed pulse laser beam toward the side-pumped amplifier, the side-pumped amplifier amplifies the gain-stretched femtosecond seed pulse laser beam and outputs the femtosecond seed pulse laser beam to the dispersion compensator, the dispersion compensator is configured to reduce the dispersion of the amplified stretched femtosecond seed pulse laser beam, and the polarization isolator is further configured to receive the amplified femtosecond seed pulse laser beam from the side-pumped amplifier and direct the amplified femtosecond seed pulse laser beam to the first cloth And (4) outputting the Lag grating.
3. The femtosecond fiber laser with adjustable frequency according to a scanning path as claimed in claim 2, wherein gain ions are doped in the active fiber.
4. A femtosecond fiber laser with adjustable frequency according to scanning path as claimed in claim 3, wherein the gain ions are one or more of neodymium, ytterbium, erbium, thulium, holmium, dysprosium, or praseodymium.
5. The femtosecond fiber laser with adjustable frequency according to the scanning path as set forth in claim 4, wherein the active fiber core diameter is 6.2 μm, and the mode field diameter is 8.8 μm-9.2 μm.
6. The femtosecond fiber laser with adjustable frequency according to a scanning path of claim 1, wherein the reflectivity of the first bragg grating is equal to or higher than that of the second bragg grating.
7. The femtosecond fiber laser with adjustable frequency according to a scanning path as claimed in claim 1, wherein the fiber transmission line is a single-mode-field photonic crystal fiber with a length of 10-20 cm and a mode-field diameter of 4.8 μm.
8. The femtosecond fiber laser with adjustable frequency according to a scanning path as claimed in claim 1, wherein the wavelength of the femtosecond seed pulsed laser beam is 1030nm ± 5nm, the pulse width is less than 500fs, the pulse frequency is 120kHz, the pulse energy is 10-40 μ J, the beam diameter is 3 ± 1 μ M, the beam quality M2 is less than 1.2, the pulse energy stability is less than 2% RMS, the average power is 2.5W, and the peak power is >40 MW.
9. The femtosecond fiber laser with adjustable frequency according to a scanning path as set forth in claim 1, wherein the laser galvanometer scanning unit scans the target region along a minimum acceleration path.
10. The femtosecond fiber laser with adjustable frequency according to the scanning path as claimed in claim 9, wherein the laser galvanometer scanning unit scans the target area along the zigzag path, and the control unit adjusts the laser frequency of the self-mode-locked fiber oscillator when approaching the path retracing part; or the laser galvanometer scanning unit scans the target area in XYZ three-dimensional directions, and the control unit adjusts the laser frequency of the self-mode-locked fiber oscillator when the target area is close to the path turning part; or the laser galvanometer scanning unit carries out spiral scanning on the target area, and the control unit adjusts the laser frequency of the self-mode-locked fiber oscillator when the scanning is close to the spiral central part; or the laser galvanometer scanning unit carries out linear scanning on the target area, and the control unit adjusts the laser frequency of the self-mode-locked optical fiber oscillator when the laser galvanometer scanning unit is close to a linear end point or a retraced part.
11. A method of operating a femtosecond fiber laser with adjustable frequency according to scanning paths as claimed in any one of claims 1 to 10, comprising the following steps:
the femtosecond seed pulse laser beam output by the self-mode-locked fiber oscillator enters the first Bragg grating through a fiber transmission line;
the femtosecond seed pulse laser beam forms a second femtosecond pulse laser beam in the resonator, and the resonator widens the duration of the second femtosecond pulse laser beam and outputs the second femtosecond pulse laser beam to the amplifying unit;
the amplifying unit receives the second femtosecond pulse laser and amplifies the amplitude of the second femtosecond pulse laser to form a third femtosecond pulse laser beam, and the third femtosecond pulse laser beam returns to the first Bragg grating, is compressed for duration by the first Bragg grating and is output;
the compressed third femtosecond pulse laser beam is focused in the target area by the laser galvanometer scanning unit through an optical fiber transmission line, the laser galvanometer scanning unit scans the target area information in real time in a three-dimensional mode through a variable scanning path and transmits the information to the data analysis processing unit for analysis processing of the scanning path, and the control unit scans the path information in real time to adjust the frequency of the self-mode-locking optical fiber oscillator and generates and outputs a frequency femtosecond pulse laser beam.
12. The method of operating a femtosecond fiber laser with adjustable frequency according to a scanning path as claimed in claim 11, further comprising the steps of:
when the laser is focused on a second target area, the steps are repeated, and the control unit adjusts the frequency of the self-mode-locked fiber oscillator according to the real-time image information of the second target area, generates and outputs a second frequency femtosecond pulse laser beam.
13. The method of operating a femtosecond fiber laser with adjustable frequency according to a scanning path as claimed in claim 11, further comprising the steps of:
and when the laser is focused on a third target area, repeating the steps, and adjusting the frequency of the self-mode-locked fiber oscillator by the control unit according to the real-time image information of the third target area to generate and output a third frequency femtosecond pulse laser beam.
14. The method of claim 11, wherein the first target region is a corneal region, the second target region is at least one of a crystalline lens and a cataractous region, the third target region is at least one of a retinal and maculopathy variant region, the first frequency femtosecond pulsed laser beam has a frequency of 50 to 100kHz, the second frequency femtosecond pulsed laser beam has a frequency of 100 to 200kHz, and the third frequency femtosecond pulsed laser beam has a frequency of 50 to 100 kHz.
CN202010524571.0A 2020-06-10 2020-06-10 Femtosecond fiber laser with frequency adjustable according to scanning path and working method thereof Pending CN111600180A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010524571.0A CN111600180A (en) 2020-06-10 2020-06-10 Femtosecond fiber laser with frequency adjustable according to scanning path and working method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010524571.0A CN111600180A (en) 2020-06-10 2020-06-10 Femtosecond fiber laser with frequency adjustable according to scanning path and working method thereof

Publications (1)

Publication Number Publication Date
CN111600180A true CN111600180A (en) 2020-08-28

Family

ID=72187854

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010524571.0A Pending CN111600180A (en) 2020-06-10 2020-06-10 Femtosecond fiber laser with frequency adjustable according to scanning path and working method thereof

Country Status (1)

Country Link
CN (1) CN111600180A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112276362A (en) * 2020-11-13 2021-01-29 深圳市杰普特光电股份有限公司 Laser welding device and welding method thereof
CN115275741A (en) * 2022-07-22 2022-11-01 深圳技术大学 Pulse stretching device, pulse stretching system and laser

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112276362A (en) * 2020-11-13 2021-01-29 深圳市杰普特光电股份有限公司 Laser welding device and welding method thereof
CN115275741A (en) * 2022-07-22 2022-11-01 深圳技术大学 Pulse stretching device, pulse stretching system and laser

Similar Documents

Publication Publication Date Title
US6757310B2 (en) Solid-state laser for customized cornea ablation
US7626758B2 (en) Method and apparatus for controlling and protecting pulsed high power fiber amplifier systems
US10859888B2 (en) System for generating brief or ultra-brief light pulses
EP0609978A1 (en) Variable repetition rate picosecond laser
CN111600180A (en) Femtosecond fiber laser with frequency adjustable according to scanning path and working method thereof
JP2013520847A (en) High-power femtosecond laser with adjustable repetition rate and simplified structure
JP2012512539A (en) Pulse laser having optical fiber for L-band high energy subpicosecond pulse, and laser device for ophthalmic surgery
CA2456445A1 (en) Suppression of mode-beating noise in a q-switched pulsed laser using novel q-switch device
AU2018235246B2 (en) Laser device for material processing
US20210260401A1 (en) Medical laser system
US20140269786A1 (en) Continuously variable pulse-width, high-speed laser
CN212571667U (en) Femtosecond fiber laser with frequency adjustable according to scanning path
TW201228161A (en) Mode locked fiber laser system
CN212571666U (en) Femtosecond fiber laser with frequency adjustable according to image information
CN212571665U (en) Femtosecond fiber laser with frequency capable of being positioned and adjusted in real time according to eye tissues
CN111600182A (en) Femtosecond fiber laser with adjustable frequency according to image information and working method thereof
CN111600181A (en) Femtosecond fiber laser with frequency capable of being positioned and adjusted in real time according to eye tissues and working method thereof
WO2019117808A1 (en) Laser system and method of forming the same
JP2012038895A (en) Fiber laser light source and wavelength conversion laser light source using the same
US20140276672A1 (en) Stable mode-locked laser apparatus
CN105390933B (en) Laser device and laser machine
Pal et al. COM stone dusting and soft tissue ablation with Q-switched thulium fiber laser
Cerný et al. Actively stabilised diode pumped Tm: YAlO laser
US20240055817A1 (en) Duration-tunable high-energy picosecond pulsed optical fibre laser system and use of such laser system
US20230223729A1 (en) Mode-lockable ring oscillator and associated methods

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination