CN207994331U - A kind of full polarization fibre mode-locked laser of the high single pulse energy of low-repetition-frequency - Google Patents
A kind of full polarization fibre mode-locked laser of the high single pulse energy of low-repetition-frequency Download PDFInfo
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- CN207994331U CN207994331U CN201820449539.9U CN201820449539U CN207994331U CN 207994331 U CN207994331 U CN 207994331U CN 201820449539 U CN201820449539 U CN 201820449539U CN 207994331 U CN207994331 U CN 207994331U
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Abstract
The utility model discloses a kind of full polarization fibre mode-locked lasers of the high single pulse energy of low-repetition-frequency, are related to Fiber laser technology.Fiber optic splitter, the second pumping source, the second polarization-maintaining gain fibre constitute nonlinear amplified loop mirror；Pulse is divided into two-beam by beam splitter, is returned and is interfered on beam splitter with clockwise transmission counterclockwise respectively, and nonlinear amplified loop mirror plays the role of fast saturable absorber in mode locked fiber laser and realizes mode locking；Realize that the ultrashort pulse of the high single pulse energy of low-repetition-frequency exports by power pre-amplification, main power amplification and dispersion compensation again.The structure greatly reduces the threshold value of mode locking startup, reduces repetition rate, simplifies Optical Maser System while improving whole stability and reliability.
Description
Technical field
The utility model is related to all risk insurance of Fiber laser technology more particularly to a kind of high single pulse energy of low-repetition-frequency is inclined
Optical fiber mode locked laser.
Background technology
The demand in growing high-precision micro Process market proposes the peak power and repetition rate of laser pulse
Higher requirement, nanosecoud pulse laser generally cannot be satisfied the requirement of retrofit.It is at low cost, stability is high, high-gain
The ultrashort pulse fiber laser of amplification causes the extensive concern of people.These advantages are for industrial materials processing laser
It is particularly important.It is being operated in the past picosecond or the low-repetition-frequency of femtosecond region, the high power laser of high single pulse energy
It is that clamping system carries out pulse choice reduction repetition rate by acousto-optic modulator or electrooptic modulator mostly, is used for after amplification
High-precision micro Process.Usual mode locking oscillator is combined and passes through regenerative amplifier with pulse selector, often leads in this way
Systems bulky, complexity are high, expensive, system stability is poor.It is these fields of representative to ultrafast laser using industry
Under various circumstances, more stringent requirements are proposed for the stability of operating for device, and technical grade ultrafast laser especially seed source
Stability and reliability are not well solved always.The seed source technology of solid is replaced to itself have using optical fiber technology
Many advantages, having for environment transformation can be resisted by being more considered using the laser of full polarization fibre in optical fiber technology
Efficacious prescriptions method.
The mode locking mechanism of full polarization fibre mode-locked laser mainly has non-linear loop speculum, saturable absorption at present
Body.Semiconductor saturable absorber has the service life in saturable absorber, is easily damaged；Other carbon-based saturable absorbers, such as
Carbon nanotube, graphene etc. are easy to deteriorate in a natural environment, lose mode locking startup function.Claude Aguergaray etc.
What people delivered in 2012 on Optics Express《Mode-locked femtosecond all-normalall-PM
Yb-doped fiber laser using anonlinear amplifying loop mirror》Paper reports that all risk insurance is partially non-
Linear loop reflector modulus-locking laser.The 8 font mode locked fiber lasers that non-linear loop speculum is constituted can utilize complete
Polarization maintaining optical fibre structure carries out mode locking, but the repetition rate of the optical fiber laser of all which mode lockings is all in a megahertz amount at present
Grade or more, it is difficult to realize hundred kHz magnitude repetition rates, picosecond or femtosecond magnitude pulse width optical fiber laser.
Utility model content
Technical problem to be solved in the utility model is：
In order to directly obtain the hundred high single pulse energies of kHz repetition rates, self-starting is well and mode locking steady in a long-term
Pulse laser, the utility model proposes a kind of full polarization fibre mode-locked lasers of low-repetition-frequency single pulse energy.
The utility model uses following technical scheme to solve above-mentioned technical problem：
A kind of full polarization fibre mode-locked laser of the high single pulse energy of low-repetition-frequency, which is characterized in that described low heavy
The full polarization fibre mode-locked laser of the high single pulse energy of complex frequency includes：First wavelength division multiplexer, the second wavelength division multiplexer,
One pumping source, the second pumping source, the first polarization-maintaining gain fibre, the second polarization-maintaining gain fibre, bandpass filter, fiber coupler,
Fiber optic splitter, fibre optic isolater, small-power image intensifer, main power image intensifer and dispersion compensation device；Wherein, optical fiber point
Beam device is 2 ' 2 beam splitters, including first to fourth port；There are three ends for first wavelength division multiplexer and the second wavelength division multiplexer
Mouth, respectively signal input port, pump ports, public port；The fiber coupler has public port, the first output port
With three ports of second output terminal mouth；
First pumping source is connect with the pump ports of first wavelength division multiplexer；The first polarization-maintaining gain fibre
One end connect with the first wavelength division multiplexer common end, the other end is connect with the input terminal of the fibre optic isolater；Isolator is defeated
Exit port is connect with the beam splitter first port；The beam splitter second port is connect with fiber coupler public port, the
Three ports are connect with the second wavelength division multiplexer signal input part, one end of the 4th port and the second polarization-maintaining gain fibre
Connection；Second pumping source is connect with the pumping end of the second wavelength division multiplexer；The common end of second wavelength division multiplexer and second
The other end of polarization-maintaining gain fibre connects.One end of the bandpass filter and the first output port of fiber coupler connect,
The other end is connect with the signal input port of the first wavelength division multiplexer；Pulse laser is defeated from fiber coupler second output terminal mouth
Go out, be incident to the small-power image intensifer, enters back into the main power image intensifer；Pulse laser is finally by dispersion compensation
Device exports after carrying out pulse compression.
A kind of foregoing full polarization fibre mode-locked laser of the high single pulse energy of low-repetition-frequency, further,
Including hundred meters of magnitude polarization maintaining optical fibres, are arranged between bandpass filter and the first wavelength division multiplexer, repeated to reduce laser
Frequency.
A kind of foregoing full polarization fibre mode-locked laser of the high single pulse energy of low-repetition-frequency, further,
Polarization maintaining optical fibre used is using polarization-maintaining single-mode fiber, big mode field area polarization maintaining optical fibre, doping gain polarization maintaining optical fibre, big mode field area
It is one or more in double clad polarization maintaining optical fibre and polarization-maintaining photonic crystal fiber.
A kind of foregoing full polarization fibre mode-locked laser of the high single pulse energy of low-repetition-frequency, further,
The dispersion compensation device is using prism to, grating to the one or more of, chirped mirror centering.
The utility model has the following technical effects using above technical scheme is compared with the prior art：
The full polarization fibre mode-locked laser of the high single pulse energy of low-repetition-frequency described in the utility model, in oscillator
Including hundred meters of magnitude polarization maintaining optical fibres, pulse recurrence frequency is less than 1MHz, and pulse spectrum width is more than 5nm, compresses afterpulse width
It can reach picosecond or femtosecond magnitude；
The optical fiber laser of the utility model can be obtained self-starting mode-locked laser pulse row, and the characteristic of spike train not by
The interference of external environment；Whole stability and reliability are improved using full polarization fibre structure simultaneously；
Laser oscillation intracavitary described in the utility model includes two wavelength division multiplexers, two gain fibres and two pumpings
Source, directly hundred kHz magnitudes of output are repetitive frequency pulsed, enormously simplify the high single pulse energy mode-locked fiber lasers of low-repetition-frequency
The system of device.
Description of the drawings
Fig. 1 is the schematic diagram of the utility model embodiment one.
Specific implementation mode
The technical solution of the utility model is described in further detail below in conjunction with the accompanying drawings.
Those skilled in the art of the present technique are it is understood that unless otherwise defined, all terms used herein（Including skill
Art term and scientific terminology）With meaning identical with the general understanding of the those of ordinary skill in the utility model fields
Justice.It should also be understood that those terms such as defined in the general dictionary should be understood that with upper with the prior art
The consistent meaning of meaning hereinafter, and unless defined as here, will not with the meaning of idealization or too formal come
It explains.
In the utility model, the first pumping source is connect with the pump ports of first wavelength division multiplexer；Hundred meters are measured
One end of grade polarization maintaining optical fibre is connect with the signal input port of the first wavelength division multiplexer；One end of first polarization-maintaining gain fibre and the
One wavelength division multiplexer common end connects, and the input terminal of the other end and fibre optic isolater connects；Isolator output port and beam splitter
First port connects；Beam splitter second port is connect with fiber coupler public port, third port and the second wavelength division multiplexer
Signal input part connects, and the 4th port is connect with one end of the second polarization-maintaining gain fibre；Second pumping source and the second wavelength-division
The pumping end of multiplexer connects；The common end of second wavelength division multiplexer is connect with the other end of the second polarization-maintaining gain fibre.Band logical
One end of filter and the first output port of fiber coupler connect, and the other end is connect with hundred meters of magnitude polarization maintaining optical fibres；
By the first wavelength division multiplexer and the second wavelength division multiplexer by pumping source laser coupled to intracavitary, pump power is carried
On height to optical fiber laser threshold value, laser is made to vibrate；
Oscillation in laser forms random small-pulse effect；
Laser pulse is input to the first port of fiber optic splitter by isolator, connects the polarization-maintaining of the first and second ports
Evanescent wave in optical fiber is coupled into the polarization maintaining optical fibre of the third and fourth port of connection, to be exported from the third and fourth port；
The fiber amplifier that the pulse exported from third port is made up of the second pumping source, the second wavelength division multiplexer and the second gain fibre
Device is amplified into the 4th port；The laser pulse exported from the 4th port passes through the second gain fibre, the second wavelength division multiplexer
The fiber amplifier constituted with the second pumping source is amplified into third port；Fiber optic splitter is by the incident laser of first port
It is divided into two light propagated in opposite directions, asymmetric lower acquisition asymmetric phase difference of the amplifier in ring returns beam splitter progress
Interference enters fiber coupler from second port output；For fiber coupler by after laser beam splitter, a part of laser passes through first end
Mouthful be incident to bandpass filter and hundred meters of magnitude polarization maintaining optical fibres, be incident in the first wavelength division multiplexer, by the first pumping source and
It is incident on the oscillation circuit that entire laser is constituted in fibre optic isolater after the amplification of first polarization-maintaining gain fibre；Another part laser
It is exported from fiber coupler second port.Fiber optic splitter, the second pumping source, the second wavelength division multiplexer, the second polarization-maintaining gain light
Fibre constitutes nonlinear amplified loop mirror, and nonlinear amplified loop mirror plays fast saturable absorber in mode locked fiber laser and makees
With the transmissivity of pulse is related with two-beam nonlinear phase shift amount in nonlinear amplified loop mirror, and transmissivity is the phase of two-beam
The function of difference is moved, the introducing bigger transmissivity of phase shift offset phase-shift phase is higher, and phase-shift phase more low transmission is lower, the central part of pulse
By force, the phase-shift phase generated in nonlinear amplified loop mirror is big, so transmission is high, pulse is more prone to form oscillation, to make
The effect that nonlinear amplified loop mirror realizes fast saturable absorber is obtained, realizes Mode-locking For Lasers, forms ultrashort pulse output.It will
The laser of fiber coupler second port output by small-power image intensifer prevent greatly, then passing through main power light amplification
Device is amplified, and single pulse energy is amplified to burnt magnitude micro- more than 10, then carry out pulse compression by dispersion compensation device, most
Eventually realize the high single pulse energy of low-repetition-frequency picosecond or femtosecond pulse output.
The optical fiber laser of the utility model can be obtained self-starting mode-locked laser pulse row, and the characteristic of spike train not by
The interference of external environment；Using all pulse shaping mechanism that can be used in nonlinear polarization rotation mode locked fiber laser,
Including orphan, self similarity, Totally positive dispersion and amplification self similarity etc..Pulse recurrence frequency is less than 1MHz, and pulse spectrum width is more than
5nm, compression afterpulse width can reach picosecond or femtosecond magnitude.Spatial dispersion compensation device such as prism is to, grating to, Zhou
Mirror of singing is reciprocity.
Polarization maintaining optical fibre is using polarization-maintaining single-mode fiber, big mode field area polarization maintaining optical fibre, doping gain polarization maintaining optical fibre, big mode field
It is one or more in product double clad polarization maintaining optical fibre and polarization-maintaining photonic crystal fiber, thought highly of by changing fiber lengths change laser
Complex frequency.
Embodiment one
As shown in Figure 1, in the present embodiment, the full polarization fibre laser of the high single pulse energy of low-repetition-frequency includes：The
One wavelength division multiplexer 1, the second wavelength division multiplexer 7, the first pumping source 2, the second pumping source 8, the first polarization-maintaining gain fibre 11, second
Polarization-maintaining gain fibre 6, hundred meters of magnitude polarization maintaining optical fibres 3, bandpass filter 4, fiber coupler 5, fiber optic splitter 9, Fiber isolations
Device 10, small-power image intensifer 12, main power image intensifer 13, dispersion compensation device 14；Wherein, fiber optic splitter 9 is 2 ' 2 points
Beam device, including first to fourth port；There are three ports for first wavelength division multiplexer 1 and the second wavelength division multiplexer 7, respectively believe
Number input port, pump ports, public port；Fiber coupler 5 has public port, the first output port and second output terminal mouth
Three ports；First pumping source 2 is connect with the pump ports of the first wavelength division multiplexer 1；Hundred meters of magnitude polarization maintaining optical fibres 3 and first wave
The signal input port of division multiplexer 1 connects；One end of first polarization-maintaining gain fibre 11 connects with 1 common end of the first wavelength division multiplexer
It connects, the other end of the first polarization-maintaining gain fibre 11 is connect with the input terminal of fibre optic isolater 10；10 output port of isolator with point
9 first port of beam deviceConnection；9 second port of beam splitterIt is connect with 5 public port of fiber coupler, third portWith
Two wavelength division multiplexers, 7 signal input part connects, the 4th portIt is connect with one end of the second polarization-maintaining gain fibre 6；Second pumping
Source 8 is connect with the pumping end of the second wavelength division multiplexer 7；The common end of second wavelength division multiplexer 7 and the second polarization-maintaining gain fibre 6
The other end connects.One end of bandpass filter 4 is connect with the first output port of fiber coupler 5, bandpass filter 4 it is another
End is connect with hundred meters of magnitude polarization maintaining optical fibres 3；
By the first wavelength division multiplexer 1 and the second wavelength division multiplexer 7 by pumping source laser coupled to intracavitary, by pump power
It is increased on optical fiber laser threshold value, laser is made to vibrate；Oscillation in laser forms random small-pulse effect；Laser arteries and veins
Punching is transferred into the first port of fiber optic splitter 9 by isolator 10, connect first portAnd second portGuarantor
Evanescent wave in polarisation fibre is coupled into connection third portWith the 4th portPolarization maintaining optical fibre in, to from third port
With the 4th portOutput；From third portThe pulse of output passes through the second pumping source 8, the second wavelength division multiplexer 7 and second
The fiber amplifier that polarization-maintaining gain fibre 6 is constituted is amplified into the 4th port；From the 4th portThe laser pulse of output
The fiber amplifier being made up of the second polarization-maintaining gain fibre 6, the second wavelength division multiplexer 7 and the second pumping source 8 is amplified into
Third port；Fiber optic splitter 9 is by first portIncident laser be divided into two light propagated in opposite directions, amplifier is in ring
It is asymmetric it is lower obtain asymmetric phase difference, return beam splitter 9 and interfered from second portOutput enters fiber coupling
Device 5；For fiber coupler 5 by after laser beam splitter, a part of laser is incident to bandpass filter 4 and hundred meters of magnitudes by first port
Polarization maintaining optical fibre 3 is incident in the first wavelength division multiplexer 1, by entering after the first pumping source 2 and the amplification of the first polarization-maintaining gain fibre 11
It is mapped to the oscillation circuit that entire laser is constituted in fibre optic isolater 10；Another part laser is from 5 second port of fiber coupler
Output.Fiber optic splitter 9, the second pumping source 8, the second wavelength division multiplexer 7, the second polarization-maintaining gain fibre 6 constitute nonlinear amplification
Annular mirror, nonlinear amplified loop mirror play the role of fast saturable absorber, the transmissivity of pulse in mode locked fiber laser
Related with two-beam nonlinear phase shift amount in nonlinear amplified loop mirror, transmissivity is the function of the phase shift difference of two-beam, is introduced
Phase shift offset phase-shift phase is bigger, and transmissivity is higher, and phase-shift phase more low transmission is lower, and the central part of pulse is strong, in nonlinear amplification
The phase-shift phase generated in annular mirror is big, so transmission is high, pulse is more prone to form oscillation, so that nonlinear amplification is annular
Mirror realizes the effect of fast saturable absorber, realizes Mode-locking For Lasers, forms ultrashort pulse output.By fiber coupler 5 second
The laser of port output carries out pre-amplification by small-power image intensifer 12, is then amplified by main power amplifier 13,
Single pulse energy is amplified to burnt magnitude micro- more than 10, then pulse compression is carried out by dispersion compensation device 14, is finally realized low
The femtosecond or picosecond pulse of the high single pulse energy of repetition rate export.
The above is only some embodiments of the utility model, it is noted that for the common skill of the art
For art personnel, without departing from the principle of this utility model, several improvements and modifications can also be made, these improve and
Retouching also should be regarded as the scope of protection of the utility model.
Claims (4)
1. a kind of full polarization fibre mode-locked laser of the high single pulse energy of low-repetition-frequency, which is characterized in that the low repetition
The full polarization fibre mode-locked laser of the high single pulse energy of frequency includes：First wavelength division multiplexer, the second wavelength division multiplexer, first
Pumping source, the second pumping source, the first polarization-maintaining gain fibre, the second polarization-maintaining gain fibre, bandpass filter, fiber coupler, light
Fine beam splitter, fibre optic isolater, small-power image intensifer, main power image intensifer and dispersion compensation device；Wherein, fiber beam splitting
Device is 2 ' 2 beam splitters, including first to fourth port；First wavelength division multiplexer and the second wavelength division multiplexer there are three port,
Respectively signal input port, pump ports, public port；The fiber coupler have public port, the first output port and
Three ports of second output terminal mouth；
First pumping source is connect with the pump ports of first wavelength division multiplexer；The one of the first polarization-maintaining gain fibre
End is connect with the first wavelength division multiplexer common end, and the other end is connect with the input terminal of the fibre optic isolater；Isolator output end
Mouth is connect with the beam splitter first port；The beam splitter second port is connect with fiber coupler public port, third end
Mouth is connect with the second wavelength division multiplexer signal input part, and the 4th port and one end of the second polarization-maintaining gain fibre connect
It connects；Second pumping source is connect with the pumping end of the second wavelength division multiplexer；The common end of second wavelength division multiplexer is protected with second
The other end connection of inclined gain fibre；One end of the bandpass filter and the first output port of fiber coupler connect, separately
One end is connect with the signal input port of the first wavelength division multiplexer；Pulse laser is exported from fiber coupler second output terminal mouth,
It is incident to the small-power image intensifer, enters back into the main power image intensifer；Pulse laser is filled finally by dispersion compensation
It sets and is exported after carrying out pulse compression.
2. a kind of full polarization fibre mode-locked laser of the high single pulse energy of low-repetition-frequency as described in claim 1, special
Sign is, including hundred meters of magnitude polarization maintaining optical fibres, are arranged between bandpass filter and the first wavelength division multiplexer, to reduce laser
Think highly of complex frequency.
3. a kind of full polarization fibre mode-locked laser of the high single pulse energy of low-repetition-frequency as described in claim 1, special
Sign is that polarization maintaining optical fibre used uses polarization-maintaining single-mode fiber, big mode field area polarization maintaining optical fibre, adulterates gain polarization maintaining optical fibre, is big
It is one or more in mode field area double clad polarization maintaining optical fibre and polarization-maintaining photonic crystal fiber.
4. a kind of full polarization fibre mode-locked laser of the high single pulse energy of low-repetition-frequency as described in claim 1, special
Sign is, the dispersion compensation device is using prism to, grating to the one or more of, chirped mirror centering.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110350387A (en) * | 2018-04-02 | 2019-10-18 | 雷小权 | A kind of full polarization fibre mode-locked laser of the high single pulse energy of low-repetition-frequency |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110350387A (en) * | 2018-04-02 | 2019-10-18 | 雷小权 | A kind of full polarization fibre mode-locked laser of the high single pulse energy of low-repetition-frequency |
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