CN104466669A - Tunable laser device - Google Patents
Tunable laser device Download PDFInfo
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- CN104466669A CN104466669A CN201310434383.9A CN201310434383A CN104466669A CN 104466669 A CN104466669 A CN 104466669A CN 201310434383 A CN201310434383 A CN 201310434383A CN 104466669 A CN104466669 A CN 104466669A
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Abstract
The invention discloses a tunable laser device which comprises a semiconductor refrigerator, a transitional heat sink, a laser device array chip, a micromotor, an optical fiber, a first splitter, a mode switcher, a single mode fiber, a second splitter, a wavelength locker, an optical detector, a laser device array chip drive circuit, a temperature control circuit, a micromotor drive circuit and a microprocessor. A sliding block capable of moving in the stoke direction of the micromotor is arranged on the micromotor, the optical fiber is fixed to the sliding block of the micromotor, the end, fixedly connected with the sliding block, of the optical fiber is a laser incoming end, and the other end of the optical fiber is connected with the mode switcher. The first splitter is connected with the mode switcher and the second splitter through the single mode fiber, and the other end of the second splitter is further connected with the wavelength locker and the optical detector. The transitional heat sink is fixed to the top of the semiconductor refrigerator, and the laser device array chip is fixed to the top of the transitional heat sink. The tunable laser device has the advantages of being low in power consumption, high in precision, low in cost and the like.
Description
Technical field
The invention belongs to LASER Light Source field, refer more particularly to a kind of tunable laser, be applicable to the Wavelength tunable laser of communication and sensing.
Background technology
Tunable laser is the laser that can continuously change laser output wavelength in a wavelength range, it is of many uses, can be used for spectroscopy, photochemistry, medical science, biology, integrated optics, pollution monitoring, semi-conducting material processing, information processing and communicates.Along with WDM(wavelength division multiplexing) technology more and more applies at fiber optic communication field, tunable laser by be now and future an each colleges and universities and research emphasis of scientific research institution, in addition domestic optical communication enterprise is faced with the pressure of industry technology upgrade, and this will expedite the emergence of market greatly to tunable laser instrument demand.But current actual conditions are that the type product relies on import substantially, not only expensive and monopolized by overseas enterprise few in number.
Realize the tuning principle of optical maser wavelength and roughly have three kinds.Most of tunable laser all uses the operation material with wide fluorescent line.The resonant cavity forming laser only just has very low loss in very narrow wave-length coverage.Therefore, the first is the wavelength being changed laser by some element (as grating) wavelength changed corresponding to resonant cavity low-loss district.The second is the energy shift making laser transition by changing some external parameter (as magnetic field, temperature etc.).The third utilizes nonlinear effect to realize the conversion of wavelength and tuning (see nonlinear optics, stimulated Raman scattering, light two frequency multiplication, optical parametric oscillation).
The tuning principle that realizes of external semiconductor laser with tunable mainly can be divided into three kinds at present: electric current tuning, thermal tuning and mechanical tuning, and selected semiconductor laser light source also determined by tuning manner.
Electric current tuning realizes the tuning of wavelength by changing Injection Current, and its tuned speed is ns rank, is mainly used in SG-DBR(sampling grating DBR) assist grating directional couple to sample reflection dorsad with GCSR() laser.Its General Principle is by changing the fiber grating of diverse location and the electric current of phase control part in tunable laser, making the relative index of refraction of fiber grating change, produce different spectrum.The selection of specific wavelength is carried out in the superposition of the different spectrum produced by zones of different fiber grating, thus produces the laser of the specific wavelength needed.Change echo area material effective refractive index by the Injection Current changing Bragg grating district, front and back, bragg wavelength changes thereupon, completes the coarse adjustment of wavelength.Then the electric current in control phase district makes chamber mould unanimously realize fine tuning with the reflection peak of echo area.But this type tunable laser exists mode hopping problem, stability during laser works can be had a strong impact on.
Thermal tuning is adjustment laser cavity temperature thus realizes wavelength change, is mainly used in Distributed Feedback Laser.In module, general built-in FP etalon and luminous power detect, separately have two independently TEC mono-be used for controlling the wavelength of laser, one is used for guaranteeing FP etalon and the work of optical power detector constant temperature.Operating temperature range when-10 degree are to 50 degree, tunable about 6nm, but required tuning period is a second rank.
Mechanical tuning generally adopts MEMS to realize, and is applicable to DFB structure and vcsel structure.Tunable laser mainly comprises dfb laser array or VCSEL laser array and MEMs part and controls and slave part with other.By selecting the specific wavelength needed of control MEMs part, thus export the light of the specific wavelength needed.Tunable laser tuning period based on this principle is generally a millisecond rank.
Summary of the invention
The object of the present invention is to provide a kind of tunable laser, the present invention be low in energy consumption, height is accurate, low cost.
The technical solution realizing the object of the invention is: a kind of tunable laser, comprises semiconductor cooler, transition heat sink, laser array chip, electrical micro-machine, optical fiber, the first splitter, mode converter, monomode fiber, the second splitter, wavelength locker, photo-detector, laser array chip drive circuit, temperature control circuit, micromotor drive circuit and microprocessor; Electrical micro-machine is provided with the slide block that can move along electrical micro-machine stroke directions, and optical fiber is fixed on the slide block of electrical micro-machine, and one end that optical fiber and slide block are fixed is laser incidence end, other end connection mode transducer; First splitter is connected with mode converter and the second splitter respectively by monomode fiber, and the other end of the second splitter is connected with wavelength locker and photo-detector again; Transition heat sink is fixed on semiconductor cooler top, laser array chip is fixed on transition heat sink top, laser array chip drive circuit connecting laser array chip provides drive current for it, semiconductor cooler is connected with laser array chip, and temperature control circuit connects semiconductor cooler and controls laser array chip temperature; Laser array chip drive circuit is connected with microprocessor respectively with temperature control circuit, the signal of telecommunication of laser array chip drive circuit and temperature control circuit provides output by microprocessor, and laser array chip drive circuit provides bias current to laser array chip work; The signal of telecommunication of micromotor drive circuit provides output by microprocessor, and micromotor drive circuit drives electrical micro-machine work; The light signal that laser array chip exports externally carries out data output from the first splitter by the first port, then connects the second splitter by the second port and carry out Data Detection; Wherein, the second splitter first port connects the wavelength parameter in wavelength locker sensed light signal, and the second port connects the power parameter in photo-detector sensed light signal, completes the Data Detection to light signal; These detect data and feed back to microprocessor again, thus maintain the normal work of whole system.
Array laser is the bar stripe shape dfb laser array of 1 × N, and N is natural number.
Electrical micro-machine integrated motion precision is 1um, and electrical micro-machine is the motor that diameter is less than 160mm or rated power and is less than 750W.
Optical fiber is communication class special optical fiber.
Mode converter realizes the conversion of optical fiber to monomode fiber, and typical loss is 3dB.
Wavelength locker is used for feedback wavelength shifted signal to microprocessor.
Photo-detector is photodiode, and the laser in coupled into optical fibres is converted to electric current, and its current feedback carrys out control micro electric machine drive circuit to microprocessor makes optical fiber reach Best Coupling position to control stroke.
Laser array chip drive circuit, temperature control circuit, micromotor drive circuit and microprocessor are integrated in a PCB.
The splitting ratio of the feedback port of the first splitter is 1%-10%; The splitting ratio of the second splitter first port is 50%.
The present invention compared with prior art, its remarkable advantage: 1, higher coupling efficiency: optical fiber adopts grinding core to burn after ball, can reach more than 95% with the coupling efficiency of chip of laser.It is comparatively large that monomode fiber tolerance compared by optical fiber, and existing general micromachine precision can meet the requirement of higher coupling efficiency in motor adjustment process.Add the loss of splitter and mode converter, the coupling efficiency of this tunable laser can reach more than 45%.
2, tuning bandwidth is large: this programme adopts laser array chip+semiconductor cooler thermal tuning to realize tunable laser.General single chips changes temperature 10 degree, wavelength shift 1nm, changing 40 degree can the bandwidth of stable regulation 4nm, and in this programme, only need improve number of chips can realize super large-scale bandwidth tuning, and the array of 8 chips can realize the full C-band wavelength tuning of 32nm.
3, low cost: the core laser array chip used in this programme makes for autonomous Design, ensure the consistency of chip wavelength interval, the DBR chip of laser of cost general tunable laser on market, remaining part is all the existing mature technology in market, only need adjust a little.
Accompanying drawing explanation
Fig. 1 is the general structure schematic diagram of tunable laser of the present invention.
Fig. 2 is the schematic diagram of tunable laser of the present invention.
Embodiment
Below in conjunction with accompanying drawing, the present invention is described in further detail.
Composition graphs 1 and Fig. 2, a kind of tunable laser, is made up of semiconductor cooler 1, transition heat sink 2, laser array chip 3, electrical micro-machine 4, optical fiber 5, first splitter 6, mode converter 7, monomode fiber 11, second splitter 8, wavelength locker 9, photo-detector 10, laser array chip drive circuit, temperature control circuit, micromotor drive circuit and microprocessor.The tunable implementation method of the present invention is undertaken tentatively tuning, then carries out precision tuning by electric current and temperature.Therefore, laser array chip drive circuit provides suitable output current driving laser array chip, and temperature control circuit provides suitable working temperature to array laser chip 3 by semiconductor cooler 1, above-mentioned two drive circuits ensure that the normal running conditions of array laser chip 3 also can realize the precision tuning of electric current and temperature.And the tentatively tuning of machinery is that micromotor drive circuit drives electrical micro-machine 4 work to drive optical fiber 5 to be coupled, the realization of its coupling process drives electrical micro-machine 4 by microprocessor by control micro electric machine drive circuit, make its linear scanning carrying out one dimension (unclear and coherent, can make pauses in reading unpunctuated ancient writings), scanning direction is consistent with the orientation along array laser chip 3.The light signal that in scanning process, laser array chip 3 exports can enter in optical fiber 5, through mode converter 7, light signal is proceeded in monomode fiber 11 again, monomode fiber 11 externally carries out data output through the first splitter 6 by the first port, connect the second splitter 8 by the second port again and carry out Data Detection, wherein the optimum light splitting ratio going out optical port and feedback port of the first splitter 6 is 9:1.Moreover, second splitter 8 first port connects the wavelength parameter in wavelength locker 9 sensed light signal, second port connects the power parameter in photo-detector 10 sensed light signal, complete the Data Detection to light signal, wherein the first port of the second splitter 8 and the optimum light splitting ratio of the second port are 1:1.Above-mentioned photo-detector 10 detects that luminous power parameter feeds back to microprocessor again, and microprocessor carrys out control micro electric machine adjustment fiber position, until optical power value reaches predetermined optical power value thus completes the coupling operational of electrical micro-machine 4 according to the size of luminous power.And the wavelength parameter that wavelength locker 9 obtains also feeds back to microprocessor, microprocessor 4 controls array laser chip drive circuit and temperature control circuit according to the difference of gained wavelength and preset wavelength, until gained wavelength value reaches presetting light wave long value, thus complete whole wavelength tuning work.
Laser array chip drive circuit is current driving circuit, and the voltage signal provided by microprocessor converts current signal to and sends corresponding light signal with drive laser array chip; Temperature control circuit drives semiconductor cooler control temperature, is temperature signal, to ensure that laser array chip is operated in suitable temperature environment by the transform electrical signals of microprocessor; Micromotor drive circuit drives electrical micro-machine work and drives optical fiber to move, and its function is low is the spatial movement amount of optical fiber by the transform electrical signals of microprocessor; Microprocessor is the information processing centre controlled this system.
A kind of tunable laser, laser array chip 3 is four dfb laser array chips, at semiconductor cooler 1(TEC) under temperature control 25 degree, wavelength is respectively 1529.55nm, 1532.68nm, 1535.82nm, 1538.98nm(and meets ITU-T optical communication standard).Drive circuit for laser provides bias current to laser array chip, and temperature control circuit is used for regulating the temperature of semiconductor cooler 1, and the rectilinear path of Microprocessor S3C44B0X electrical micro-machine 4 makes optical fiber be coupled with the laser array chip 3 of required passage.Coupling output is connected to mode converter 7, transfers monomode fiber 11 to.Monomode fiber 11 connects the first splitter 6, and wherein 95% end exports, and 5% termination enters the second splitter 8.Second splitter 8 by light 1:1 along separate routes, then accesses photo-detector 10 and wavelength locker 9 respectively.Electrical micro-machine control circuit realizes being coupled of optical fiber and laser array chip 3 by detecting the electric current of photo-detector 10 and then control micro electric machine.Meanwhile, whether wavelength locker 9 determined wavelength reaches preset wavelength, and differential signal is fed back to microprocessor, and microprocessor regulates temperature by temperature control circuit, controls wavelength.
Optical fiber 5 adopts 100/125 multimode fiber, motor: three association SM06
Embodiment one, the 1st step, only give first passage chip power supply about 30mA in laser array chip, TEC temperature 25 degree, optical fiber and first laser alignment, realize output wavelength 1532.68nm; 2nd step, by the feedback of wavelength locker 9, improving TEC temperature is about 33 degree, output wavelength 1533.48nm; 3rd step, by the feedback of wavelength locker 9, improving TEC temperature is about 41 degree, output wavelength 1534.28nm; 4th step, by the feedback of wavelength locker 9, improving TEC temperature is about 49 degree, output wavelength 1535.08nm; 5th step, only gives second channel chip power supply about 30mA in laser array chip, by the feedback of photo-detector 10, drive motors regulates optical fiber to aim at second channel chip, by the feedback of wavelength locker 9, TEC temperature is regulated to be 25 degree, output wavelength 1535.82nm; 5th step, by the feedback of wavelength locker 9, regulates TEC temperature to be 33 degree, output wavelength 1536.62nm; By that analogy, realize 12nm bandwidth, the tunable laser at 0.8nm interval exports.
The above; it is only preferred embodiment of the present invention; not the present invention is imposed any restrictions, every above embodiment is done according to the technology of the present invention essence any simple modification, change and equivalent structure change, all still belong in the protection range of technical solution of the present invention.
Claims (9)
1. a tunable laser, is characterized in that: comprise semiconductor cooler (1), transition heat sink (2), laser array chip (3), electrical micro-machine (4), optical fiber (5), the first splitter (6), mode converter (7), monomode fiber (11), the second splitter (8), wavelength locker (9), photo-detector (10), laser array chip drive circuit, temperature control circuit, micromotor drive circuit and microprocessor; Electrical micro-machine (4) is provided with can along the slide block of electrical micro-machine (4) stroke directions motion, and optical fiber (5) is fixed on the slide block of electrical micro-machine (4), and one end that optical fiber (5) is fixed with slide block is laser incidence end, other end connection mode transducer (7); First splitter (6) is connected with mode converter (7) and the second splitter (8) respectively by monomode fiber (11), and the other end of the second splitter (8) is connected with wavelength locker (9) and photo-detector (10) again; Transition heat sink (2) is fixed on semiconductor cooler (1) top, laser array chip (3) is fixed on transition heat sink (2) top, laser array chip drive circuit connecting laser array chip provides drive current for it, semiconductor cooler is connected with laser array chip (3), and temperature control circuit connects semiconductor cooler and controls laser array chip (3) temperature; Laser array chip drive circuit is connected with microprocessor respectively with temperature control circuit, the signal of telecommunication of laser array chip drive circuit and temperature control circuit provides output by microprocessor, and laser array chip drive circuit provides bias current to work to laser array chip (3); The signal of telecommunication of micromotor drive circuit provides output by microprocessor, and micromotor drive circuit drives electrical micro-machine (4) work; The light signal that laser array chip (3) exports passes through optical port from the first splitter (6) and externally carries out data output, then connects the second splitter (8) by feedback port and carry out Data Detection; Wherein, the second splitter (8) first port connects the wavelength parameter in wavelength locker (9) sensed light signal, and the second port connects the power parameter in photo-detector (10) sensed light signal, completes the Data Detection to light signal; These detect data and feed back to microprocessor again, thus maintain the normal work of whole system.
2. tunable laser according to claim 1, is characterized in that: array laser is the bar stripe shape dfb laser array of 1 × N, and N is natural number.
3. tunable laser according to claim 1, is characterized in that: electrical micro-machine (4) integrated motion precision is 1um, and electrical micro-machine (4) is less than the motor that 160mm or rated power is less than 750W for diameter.
4. tunable laser according to claim 1, is characterized in that: optical fiber (5) is communication class special optical fiber.
5. tunable laser according to claim 1, is characterized in that: mode converter (7) realizes the conversion of optical fiber (5) to monomode fiber (11), and typical loss is 3dB.
6. tunable laser according to claim 1, is characterized in that: wavelength locker (9) is used for feedback wavelength shifted signal to microprocessor.
7. tunable laser according to claim 1, it is characterized in that: photo-detector (10) is photodiode, laser in coupled into optical fibres is converted to electric current, and its current feedback carrys out control micro electric machine drive circuit to microprocessor makes optical fiber reach Best Coupling position to control stroke.
8. tunable laser according to claim 1, is characterized in that: laser array chip drive circuit, temperature control circuit, micromotor drive circuit and microprocessor are integrated on a PCB (12).
9. tunable laser according to claim 1, is characterized in that: the splitting ratio of the feedback port of the first splitter (6) is 1%-10%; The splitting ratio of the second splitter (8) first port is 50%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201310434383.9A CN104466669A (en) | 2013-09-23 | 2013-09-23 | Tunable laser device |
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| CN201310434383.9A CN104466669A (en) | 2013-09-23 | 2013-09-23 | Tunable laser device |
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| CN104466669A true CN104466669A (en) | 2015-03-25 |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107394579A (en) * | 2017-07-04 | 2017-11-24 | 浙江省广电科技股份有限公司 | A kind of RFoG optical nodes of wavelength tuning |
| CN109188614A (en) * | 2018-08-28 | 2019-01-11 | 武汉电信器件有限公司 | Dual carrier integrated optical device and optical-electric module |
| CN112985586A (en) * | 2021-02-09 | 2021-06-18 | 南方电网科学研究院有限责任公司 | Polarization maintaining light source and optical power detection integrated equipment |
| CN114221212A (en) * | 2021-12-15 | 2022-03-22 | 山东省计量科学研究院 | Stable light source for light transmission and cooling method thereof |
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Patent Citations (6)
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| US20020064192A1 (en) * | 2000-08-09 | 2002-05-30 | Mark Missey | Tunable distributed feedback laser |
| US6839364B1 (en) * | 2000-09-29 | 2005-01-04 | Triquint Technology Holding Co. | Feedback control loop operating system for tunable source |
| CN1420640A (en) * | 2001-11-17 | 2003-05-28 | 中国科学技术大学 | Multipath high-speed light emitting module |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107394579A (en) * | 2017-07-04 | 2017-11-24 | 浙江省广电科技股份有限公司 | A kind of RFoG optical nodes of wavelength tuning |
| CN109188614A (en) * | 2018-08-28 | 2019-01-11 | 武汉电信器件有限公司 | Dual carrier integrated optical device and optical-electric module |
| US11675149B2 (en) | 2018-08-28 | 2023-06-13 | Wuhan Telecommunication Devices Co., Ltd | Dual-carrier integrated optical device and photoelectric module |
| CN112985586A (en) * | 2021-02-09 | 2021-06-18 | 南方电网科学研究院有限责任公司 | Polarization maintaining light source and optical power detection integrated equipment |
| CN114221212A (en) * | 2021-12-15 | 2022-03-22 | 山东省计量科学研究院 | Stable light source for light transmission and cooling method thereof |
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