CN109361145A - Single wavelength is tunable Q-switch and mode-locking pulse laser - Google Patents
Single wavelength is tunable Q-switch and mode-locking pulse laser Download PDFInfo
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- CN109361145A CN109361145A CN201811581662.7A CN201811581662A CN109361145A CN 109361145 A CN109361145 A CN 109361145A CN 201811581662 A CN201811581662 A CN 201811581662A CN 109361145 A CN109361145 A CN 109361145A
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- 230000010287 polarization Effects 0.000 claims abstract description 29
- 239000013307 optical fiber Substances 0.000 claims abstract description 25
- 239000000835 fiber Substances 0.000 claims abstract description 24
- 239000006185 dispersion Substances 0.000 claims description 6
- 230000009286 beneficial effect Effects 0.000 claims description 2
- 238000000034 method Methods 0.000 abstract description 3
- 238000004891 communication Methods 0.000 abstract description 2
- 239000003814 drug Substances 0.000 abstract description 2
- 239000000203 mixture Substances 0.000 abstract description 2
- 230000008569 process Effects 0.000 abstract description 2
- 238000001514 detection method Methods 0.000 abstract 1
- 230000010363 phase shift Effects 0.000 description 4
- 239000006096 absorbing agent Substances 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 230000003595 spectral effect Effects 0.000 description 1
Classifications
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- 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
- H01S3/1112—Passive mode locking
-
- 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
- H01S3/05—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
- H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
- H01S3/10061—Polarization control
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- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Plasma & Fusion (AREA)
- Optics & Photonics (AREA)
- Lasers (AREA)
Abstract
The invention discloses the tunable Q-switch and mode-locking pulse lasers of Single wavelength, it include: pump light source, Unidirectional ring, two-way ring, Unidirectional ring includes: the first Polarization Controller, the unrelated isolator of polarization, output coupler, output coupler, the unrelated isolator of polarization, the first Polarization Controller pass sequentially through optical fiber and concatenate to form ring-type, and two-way ring includes: wavelength division multiplexer, er-doped gain fibre, the second Polarization Controller, single mode optical fiber.It realizes that Q-switch and mode-locking and Single wavelength are tunable using the laser cavity of Unidirectional ring and the two-way ring composition figure of eight, the first and second Polarization Controllers, can be used for the fields such as micro Process, nonlinear optics, surgical medicine, optic communication and Photoelectric Detection.
Description
Technical field
The invention is related to optical technical field, in particular to a kind of laser.
Background technique
The study found that there is a variety of operating state, such as mode locking, tune Q, Q-switch and mode-locking, continuous wave and harmonic wave in the laser
Mode locking etc..In various operating state, Q-switch and mode-locking pulse is characterized in that mode locking pulse has the macrocyclic envelope for adjusting Q.
Q-switch and mode-locking is because it has the characteristic for adjusting two kinds of operating state of Q and mode locking simultaneously in terms of the mechanism study to optical fiber laser
With its unique value.In addition, Q-switch and mode-locking pulse is in micro Process, nonlinear optics, surgical medicine and multiphoton microscope etc.
Aspect also has potential using value, therefore is widely paid close attention to and studied.
Currently, there are many technical solutions that Q-switch and mode-locking may be implemented in optical fiber laser, such as revolved based on nonlinear polarization
Turn technology, nonlinear amplification environment and semiconductor saturable absorber etc., but generates the technology of Q-switch and mode-locking, primarily directed to
Traditional Single wavelength Q-switch and mode-locking pulse.And in terms of tunable wave length, since the central wavelength of the pulse of generation can be very wide again
Spectral region in be tuned, therefore can be applied to the dense wave division multipurpose field of optic communication, can be also used for optical signal
Processing and wavelength conversion field also can be used as the light source of high-speed light switching, have very broad application prospect.
Existing laser, it is difficult to realize Q-switch and mode-locking tunable wave length.Present invention aims at can be in optical fiber laser
Realize that Q-switch and mode-locking Single wavelength is tunable.
Summary of the invention
The object of the present invention is to provide a kind of optical fiber lasers that achievable Q-switch and mode-locking Single wavelength is tunable.
The solution that the present invention solves its technical problem is: Single wavelength is tunable Q-switch and mode-locking pulse laser, comprising:
Pump light source, Unidirectional ring, two-way ring, the Unidirectional ring include: the first Polarization Controller, the unrelated isolator of polarization,
Output coupler, the output coupler, the unrelated isolator of polarization, the first Polarization Controller pass sequentially through optical fiber and concatenate to form ring
Shape, the two-way ring include: wavelength division multiplexer, er-doped gain fibre, the second Polarization Controller, single mode optical fiber, and described second partially
Vibration controller, single mode optical fiber, wavelength division multiplexer, er-doped gain fibre concatenate to form ring-type by optical fiber, and the two of Unidirectional ring
End is respectively connected to a side ports of 2 × 2 fiber couplers, and the both ends of two-way ring are respectively connected to the other side of 2 × 2 fiber couplers
The output light of port, the pump light source enters the two-way ring by wavelength division multiplexer.
Further, the group velocity dispersion parameter of the er-doped gain fibre is -15ps/nm/km, the group of the single mode optical fiber
Velocity dispersion parameter is 17ps/nm/km, and the length of the er-doped gain fibre is 1.8m, and the length of the single mode optical fiber is
30m。
Further, the wavelength of the output light of the pump light source is 980nm.
The beneficial effects of the present invention are: being utilized simultaneously using the laser cavity of Unidirectional ring and the two-way ring composition figure of eight
First Polarization Controller and the second Polarization Controller realize that Q-switch and mode-locking and Single wavelength are tunable.
Detailed description of the invention
To describe the technical solutions in the embodiments of the present invention more clearly, make required in being described below to embodiment
Attached drawing is briefly described.Obviously, described attached drawing is a part of the embodiments of the present invention, rather than is all implemented
Example, those skilled in the art without creative efforts, can also be obtained according to these attached drawings other designs
Scheme and attached drawing.
Fig. 1 is the structural schematic diagram of the invention laser；
Fig. 2 is the light path schematic diagram of the laser cavity of the invention laser.
Specific embodiment
It is carried out below with reference to technical effect of the embodiment and attached drawing to design of the invention, specific structure and generation clear
Chu is fully described by, to be completely understood by the purpose of the present invention, feature and effect.Obviously, described embodiment is this hair
Bright a part of the embodiment, rather than whole embodiments, based on the embodiment of the present invention, those skilled in the art are not being paid
Other embodiments obtained, belong to the scope of protection of the invention under the premise of creative work.In addition, be previously mentioned in text
All connection/connection relationships not singly refer to that component directly connects, and referring to can be added deduct according to specific implementation situation by adding
Few couple auxiliary, to form more preferably coupling structure.Each technical characteristic in the invention, in not conflicting conflict
Under the premise of can be with combination of interactions.
Embodiment 1, with reference to Fig. 1, Single wavelength is tunable Q-switch and mode-locking pulse laser, comprising: pump light source 4, Unidirectional
Ring 1, two-way ring 2；The Unidirectional ring 1 includes: the first Polarization Controller 13, the unrelated isolator 12 of polarization, output coupler
11, the output coupler 11, the unrelated isolator 12 of polarization, the first Polarization Controller 13 pass sequentially through optical fiber and concatenate to form ring
Shape；Wherein, the incident light of specific direction can be connected in the unrelated isolator 12 of the polarization, to realize the work of one-way conduction
With.
The two-way ring 2 includes: wavelength division multiplexer 23, er-doped gain fibre 24, the second Polarization Controller 21, single mode optical fiber
22, second Polarization Controller 21, single mode optical fiber 22, wavelength division multiplexer 23, er-doped gain fibre 24 concatenate shape by optical fiber
Circlewise；The both ends of Unidirectional ring 1 are respectively connected to a side ports of 2 × 2 fiber couplers 3, and the both ends of two-way ring 2 connect respectively
Enter another side ports of 2 × 2 fiber couplers 3.As optimization, the group velocity dispersion parameter of the er-doped gain fibre 24 is-
The group velocity dispersion parameter of 15ps/nm/km, the single mode optical fiber 22 are about 17ps/nm/km, the er-doped gain fibre 24
Length is 1.8m, and the length of the single mode optical fiber 22 is 30m.The wavelength of the output light of the pump light source 4 is 980nm.
In the present embodiment, the light wave that the wavelength division multiplexer 23 is 980nm and 1550nm is multiplexed, that is, the wavelength-division multiplex
Device 23 is equipped with 980nm lightwave entry end and 1550nm lightwave entry end, wherein 980nm lightwave entry end is defeated with pump light source 4
The output light of outlet connection, the pump light source 4 enters the two-way ring 2 by wavelength division multiplexer 23.
With reference to Fig. 2, when this laser works, the light that pump light source 4 issues 980nm is entered by wavelength division multiplexer 23
In er-doped gain fibre 24, the laser of 1550nm is generated, the laser of the 1550nm is by 2 × 2 fiber couplers 3 in the list
The laser for dividing equally light intensity is issued to the both ends of operating ring 1, due to polarizing the isolation of unrelated isolator 12, so that laser is unidirectionally being transported
It is transmitted clockwise in change 1, as indicated by the arrows of fig. 2, the laser rotated clockwise is from the side of 2 × 2 fiber coupler 3
Port enters 2 × 2 fiber couplers 3, and enters two-way ring 2 from another side ports of 2 × 2 fiber coupler 3, at this point,
The laser for entering two-way ring 2 is transmitted along the both direction clockwise and anticlockwise of two-way ring 2 respectively, and two-beam passes through two-way ring
2 loop has accumulated nonlinear phase shift, simultaneously as have passed through single mode optical fiber 22 and er-doped gain fibre 24, so that laser obtains
It to positive feedback, then meets at 2 × 2 couplers 3 and interferes, and exported from the output end of output coupler 11.
This laser forms the laser cavity of the figure of eight using Unidirectional ring 1 and two-way ring 2, and two beams pass in opposite direction
Defeated light obtains different nonlinear phase shifts in two-way ring 2 after transmission primaries, and nonlinear phase shift can along pulse when
Domain profile variations.The parameter of laser cavity is suitably adjusted by the first Polarization Controller 13 and the second Polarization Controller 21, respectively
Q and tuning to be adjusted, the nearly π of fractional phase differential of pulse centre light intensity is made, transmissivity is close to 100%, thus be transmitted, and pulse
Both wings partially due to the lower gained phase shift of power is smaller, transmissivity is small, thus by reflecting.Therefore, it is exported out of two-way ring 2
The pulse of pulse ratio input is narrow, this is similar with the function of true saturable absorber.By suitably adjusting the second Polarization Control
Device 21, two-way ring 2 can be used as a wavelength selector, realize that Single wavelength is tunable, obtain the adjustable harmony Q lock of stable Single wavelength
The output of mould pulse train.
Better embodiment of the invention is illustrated above, but the invention is not limited to the implementation
Example, those skilled in the art can also make various equivalent modifications on the premise of without prejudice to spirit of the invention or replace
It changes, these equivalent variation or replacement are all included in the scope defined by the claims of the present application.
Claims (3)
1. Single wavelength is tunable Q-switch and mode-locking pulse laser, including pump light source, which is characterized in that further include: Unidirectional
Ring, two-way ring, the Unidirectional ring includes: the first Polarization Controller, polarizes unrelated isolator, output coupler, described defeated
Coupler, the unrelated isolator of polarization, the first Polarization Controller pass sequentially through optical fiber and concatenate to form ring-type out, the two-way ring packet
It includes: wavelength division multiplexer, er-doped gain fibre, the second Polarization Controller, single mode optical fiber, second Polarization Controller, single-mode optics
Fibre, wavelength division multiplexer, er-doped gain fibre concatenate to form ring-type by optical fiber, and the both ends of Unidirectional ring are respectively connected to 2 × 2 light
One side ports of fine coupler, the both ends of two-way ring are respectively connected to another side ports of 2 × 2 fiber couplers, the pump light
The output light in source enters the two-way ring by wavelength division multiplexer.
2. the tunable Q-switch and mode-locking pulse laser of Single wavelength according to claim 1, which is characterized in that the er-doped increases
The group velocity dispersion parameter of beneficial optical fiber is -15ps/nm/km, and the group velocity dispersion parameter of the single mode optical fiber is 17ps/nm/km,
The length of the er-doped gain fibre is 1.8m, and the length of the single mode optical fiber is 30m.
3. the tunable Q-switch and mode-locking pulse laser of Single wavelength according to claim 1, which is characterized in that the pump light
The wavelength of the output light in source is 980nm.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811581662.7A CN109361145B (en) | 2018-12-24 | 2018-12-24 | Single-wavelength tunable Q-mode locking pulse laser |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811581662.7A CN109361145B (en) | 2018-12-24 | 2018-12-24 | Single-wavelength tunable Q-mode locking pulse laser |
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| CN109361145A true CN109361145A (en) | 2019-02-19 |
| CN109361145B CN109361145B (en) | 2023-12-01 |
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| CN201811581662.7A Active CN109361145B (en) | 2018-12-24 | 2018-12-24 | Single-wavelength tunable Q-mode locking pulse laser |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113097844A (en) * | 2021-04-02 | 2021-07-09 | 电子科技大学 | Single frequency Q-switching laser |
| CN114935795A (en) * | 2022-07-25 | 2022-08-23 | 中国科学技术大学 | Bidirectional isolator related to polarization maintaining optical fiber fast and slow axes and bidirectional mode-locked laser |
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|---|---|---|---|---|
| KR970031506A (en) * | 1995-11-29 | 1997-06-26 | 양승택 | Tunable Soliton Fiber Laser |
| US6385216B1 (en) * | 1998-12-03 | 2002-05-07 | Electronics And Telecommunications Research Institute | Optical fiber mode-locked laser |
| CN1909306A (en) * | 2006-09-01 | 2007-02-07 | 中国科学院西安光学精密机械研究所 | '8' character cavity passive mode-locking pulse optical fibre laser |
| WO2015073257A1 (en) * | 2013-11-12 | 2015-05-21 | Imra America, Inc. | Compact fiber short pulse laser sources |
| CN108847570A (en) * | 2018-08-06 | 2018-11-20 | 佛山科学技术学院 | It is a kind of for generating the device of Q-switch and mode-locking noise like square-wave pulse |
| CN209056762U (en) * | 2018-12-24 | 2019-07-02 | 佛山科学技术学院 | Single wavelength is tunable Q-switch and mode-locking pulse laser |
-
2018
- 2018-12-24 CN CN201811581662.7A patent/CN109361145B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR970031506A (en) * | 1995-11-29 | 1997-06-26 | 양승택 | Tunable Soliton Fiber Laser |
| US6385216B1 (en) * | 1998-12-03 | 2002-05-07 | Electronics And Telecommunications Research Institute | Optical fiber mode-locked laser |
| CN1909306A (en) * | 2006-09-01 | 2007-02-07 | 中国科学院西安光学精密机械研究所 | '8' character cavity passive mode-locking pulse optical fibre laser |
| WO2015073257A1 (en) * | 2013-11-12 | 2015-05-21 | Imra America, Inc. | Compact fiber short pulse laser sources |
| CN108847570A (en) * | 2018-08-06 | 2018-11-20 | 佛山科学技术学院 | It is a kind of for generating the device of Q-switch and mode-locking noise like square-wave pulse |
| CN209056762U (en) * | 2018-12-24 | 2019-07-02 | 佛山科学技术学院 | Single wavelength is tunable Q-switch and mode-locking pulse laser |
Non-Patent Citations (1)
| Title |
|---|
| 叶雯: "基于8字型腔的自调Q多波长被动锁模光纤激光器", 《中国光学学会2010年光学大会论文集》, pages 1 - 9 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113097844A (en) * | 2021-04-02 | 2021-07-09 | 电子科技大学 | Single frequency Q-switching laser |
| CN114935795A (en) * | 2022-07-25 | 2022-08-23 | 中国科学技术大学 | Bidirectional isolator related to polarization maintaining optical fiber fast and slow axes and bidirectional mode-locked laser |
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| CN109361145B (en) | 2023-12-01 |
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