CN103779777A - Tunable laser using tunable fabry-perot filter - Google Patents
Tunable laser using tunable fabry-perot filter Download PDFInfo
- Publication number
- CN103779777A CN103779777A CN201210416719.4A CN201210416719A CN103779777A CN 103779777 A CN103779777 A CN 103779777A CN 201210416719 A CN201210416719 A CN 201210416719A CN 103779777 A CN103779777 A CN 103779777A
- Authority
- CN
- China
- Prior art keywords
- filter
- tunable
- perot
- fabry
- phase
- 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
Links
Images
Abstract
The present invention relates to a tunable laser using a tunable fabry-perot filter. The tunable laser using the tunable fabry-perot filter comprises a laser cavity end mirror, a laser gain medium, an intracavity collimating lens, an active optical phase modulator, the tunable fabry-perot filter, an output lens and a laser driving and controlling system which are arranged orderly. The tunable fabry-perot filter comprises two design schemes. The main technical features of the first design scheme are that the tunable fabry-perot filter comprises a first band pass filter, a liquid crystal phase modulator, a second band pass filter and a drive circuit, the liquid crystal phase modulator is arranged in a fabry-perot cavity formed by a first band pass filter and a second band pass filter, and the drive circuit realizes a tuning function of the filter by controlling the effective refractive index of a liquid crystal material in the fabry-perot cavity. The difference of the second design scheme and the first design scheme is that a long wavelength pass step-type filter and a short wavelength pass step-type filter which have different cut-off frequency spectrums substitute for the first and second band pass filters respectively.
Description
Technical field
The invention belongs to optoelectronic areas, especially a kind of tunable laser that uses tunable fabry-perot filter.
Background technology
In external-cavity tunable laser, conventional tunable technology mainly contains following mode: 1, drive the rotation of grating to carry out tuning by accurate stepper motor, the problem of its existence is embodied in: the one, for realizing the fine tune of light frequency, very high to the stepping accuracy of stepper motor and repeatability requirement, therefore manufacturing cost is higher; The 2nd, owing to adopting stepper motor, be difficult for accomplishing miniaturization; The 3rd, the job stability under severe operational environment is poor, and particularly the ability of anti-all kinds of mechanical oscillation is poor, therefore, adopts the tunable laser of this technology to be only suitable for using for laboratory work environment.2, utilize Acousto-optical Tunable Filters to carry out tuning, its advantage is that tuned speed is fast, there is no mechanical displacement means, can accomplish miniaturization, shortcoming is that the filtering bandwidth of Acousto-optical Tunable Filters is wider, makes the tuning precision of laser not high, therefore, the simple tunable laser that adopts this technology is difficult to accomplish precise tunable, is only suitable for for to tuning precision and the not high application of output bandwidth.3, utilize other optically filtering devices in grating or laserresonator, as the transmitted light frequencies such as optical standard tool are carried out tuning with the feature of temperature drift, its advantage is that tuning precision spectral bandwidth high and output light is narrow, shortcoming is that speed is slow, particularly in the situation that requiring tuned light spectral limit wide, this shortcoming is particularly evident, for example: the temperature drift coefficient of optically filtering device is 0.02 nanometer/degree, the spectral range requiring is 20 nanometers, temperature regulating range is 100 degree, and this is to be difficult to realize in actual applications.
Summary of the invention
The object of the invention is to overcome the deficiencies in the prior art, provide that a kind of tuned speed is fast, precision is high, cost is low, simple in structure, size is little and be easy to the tunable laser of producing.
The present invention solves existing technical problem and takes following technical scheme to realize:
A kind of tunable laser that uses tunable Fabry-Perot-type filter, comprise the laser cavity surface mirror of installing successively, gain medium, collimating lens in chamber, active optical phase modulator, tunable fabry-perot filter, outgoing mirror and laser drive and control system, form laser resonant cavity by described laser cavity surface mirror and outgoing mirror, described tunable fabry-perot filter comprises two kinds of designs: the first design comprises the first band pass filter of installing successively, liquid crystal phase-modulator, the second band pass filter and drive circuit, liquid crystal phase-modulator is arranged in the Fabry-Perot-type cavity being made up of the first band pass filter and the second band pass filter, drive circuit is realized the tuber function of filter by controlling the effective refractive index of liquid crystal material in described Fabry-Perot-type cavity, the second design comprises long-pass phase step type filter, liquid crystal phase-modulator, short-pass phase step type filter filtering device and the drive circuit installed successively, liquid crystal phase-modulator is arranged in the Fabry-Perot-type cavity being made up of long-pass phase step type filter and short-pass phase step type filter, and drive circuit is realized the tuber function of filter by controlling the effective refractive index of the liquid crystal material of liquid crystal phase-modulator in described Fabry-Perot-type cavity.The output tuning range of laser and tuning precision are determined by tuning range and the tuning precision of described tunable fabry-perot filter.
And, described the first band pass filter and the second band pass filter are two band pass filters with identical transmission bandwidth, in transmission bandwidth, there is partial reflectance, this reflectivity has determined the transmitted light acutance of described tunable fabry-perot filter, different reflectivity can be set as required, for the application of optical-fibre communications, generally between 70% to 95%, have 100% or approach 100% reflectivity outward at transmission bandwidth.
And, described long-pass phase step type filter has 100% or approach 100% reflectivity for the light that is less than cut-off frequency, there is partial reflectance for being greater than in the passband of cut-off frequency, described short-pass phase step type filter has 100% or approach 100% reflectivity for the light that is greater than cut-off frequency, there is partial reflectance for being less than in the passband of cut-off frequency, reflectivity in the passband of the reflectivity in the band of described long-pass phase step type filter and described short-pass phase step type filter is identical, this reflectivity has determined the transmitted light acutance of described tunable fabry-perot filter, different reflectivity can be set as required, reflectivity is higher, transmitted light acutance is higher, for the application of optical-fibre communications, generally between 70% to 95%, the cut-off frequency of described long-pass phase step type filter is less than the cut-off frequency of described short-pass phase step type filter.
And, described the first band pass filter, described the second band pass filter, described long-pass phase step type filter and described short-pass phase step type filter are a kind of multilayer dielectric films of the plating of the medial surface at optically transparent material, at the outside of described optically transparent material plating optical anti-reflective film.
And described gain medium is a kind of broad band laser gain media.
And described laser drives and control system comprises active phase-modulator drive source and gain medium pumping source and system, control circuit, the drive circuit of described liquid crystal phase-modulator is connected with described system, control circuit.
And described active optical phase modulator can be one of following several types: electro-optic phase modulator, acousto-optic phase-modulator, certain combination of magneto-optic phase-modulator or above-mentioned several phase-modulators.
And, liquid crystal material in described liquid crystal phase-modulator is a kind of nematic phase type liquid crystal (nematic phase liquid crystal) material, thickness is several microns to tens microns, the linearly polarized light of a direction is there is the light phase delay of at least 2 π under the driving of extra electric field, and there is the spectral region identical with described gain medium.
And the pass band width of described the first band pass filter and the second band pass filter is less than the Free Spectral Range of described tunable fabry-perot filter; After the combination of described long-pass phase step type filter and described short-pass phase step type filter, passband broadband is less than the Free Spectral Range of described tunable fabry-perot filter.
And the drive circuit of described tunable fabry-perot filter is the square-wave pulse circuit that a kind of frequency is about 2 KHz, pulse voltage amplitude from 0 volt to positive and negative 5 volts adjustable.
Advantage of the present invention and good effect are:
1, the present invention utilizes the phase-modulation of liquid crystal to light and the feature at optical direction size thin (approximately 10 microns), in conjunction with the technology of traditional Fabry-Perot (Fabry-Perot) etalon, design tunable fabry-perot (Fabry-Perot) filter with large Free Spectral Range, and the fast precise of realizing the laser frequency in broad spectrum is tuning, has guaranteed large tuned light spectral limit and narrow laser output spectrum;
2, two of the chamber of tunable fabry-perot filter of the present invention to have high reflectance face be to have the wide band pass filter of identical logical light belt by two to form, or the combination of a long-pass phase step type filter and a short-pass phase step type filter forms, utilize the tunable range of filter limits tunable fabry-perot filter, in the time that the Free Spectral Range of tunable fabry-perot filter is greater than the synthetic passband width of band pass filter or two logical phase step type filters, can realize the single-mode output of tunable fabry-perot filter;
3, the present invention is reasonable in design, can realize the stabilized lasers output that in broad spectrum light frequency tuning precision is less than 1GHz and narrow spectral bandwidth, there is machinery-free moving-member, stable and reliable for performance, cost is low, simple in structure, size is little, be easy to install and the feature such as production, can meet for the reliability service requiring under the little and extreme operational environment of size, can be widely used in the fields such as optic test, optical-fibre communications, biology, medicine equipment and Fibre Optical Sensor network.
Accompanying drawing explanation
Fig. 1 is the schematic diagram of a common law F-P etalon;
Fig. 2 is a kind of structural representation of liquid crystal phase-modulator;
Fig. 3 is that the phase place of light transmission liquid crystal phase-modulator is with the change curve of extra electric field;
Fig. 4 is the schematic diagram of the driving signal of telecommunication of liquid crystal phase-modulator;
Fig. 5 is a kind of structural representation of the present invention;
Fig. 6 is the transmitted spectrum schematic diagram of the first and second band pass filters;
Fig. 7 is the transmitted spectrum schematic diagram of long-pass step filter;
Fig. 8 is the transmitted spectrum schematic diagram of short-pass step filter;
Fig. 9 is the transmitted spectrum schematic diagram of common law F-P etalon;
Figure 10 is the transmitted spectrum schematic diagram of tunable fabry-perot filter;
Figure 11 is structural representation of the present invention;
Figure 12 is the transmitted spectrum schematic diagram of tunable laser of the present invention;
Figure 13 is the theory diagram of laser driving control system of the present invention.
Embodiment
Below in conjunction with accompanying drawing, the embodiment of the present invention is further described.
Fig. 1 has provided the schematic diagram of a kind of common Fabry-Perot (Fabry-Perot) light standard tool 100.The material of this Fabry-Perot light standard tool 100 generally uses to resemble at near-infrared and visible light wave range and melts quartz or the such optical glass of BK7, the refractive index of supposing material is n, two logical light faces 2 and 4 all plate highly reflecting films, its reflectivity is R, thickness is h, and light, to approach the incidence angle incident of zero degree, only has the 2nh=m of meeting λ, could see through etalon, wherein m is the level time of transmitted light.The Free Spectral Range FSR of light standard tool 100
1can be expressed as: Δ λ=λ
2/ (2nh), or with frequency representation: Δ ν=c/ (2nh), wherein c is the light velocity.The crest frequency of transmitted light can be expressed as: ν=mc/ (2nh), and wherein m is order of interference, the frequency bandwidth of transmitted light can be expressed as:
Δ ν
1/2(FWHM)=c (1-R)/(2nhR
1/2), wherein c is the light velocity.
Can find out the Free Spectral Range FSR of light standard tool 100 from above-mentioned two formula
1with thickness be that h is inversely proportional to.The refractive index of supposing material is n=1.5, realize FSR
1=100GHz, 1 millimeter of thickness h ≈.Free Spectral Range FSR
1larger, its thickness is just less.After the material of etalon and thickness are determined, the frequency bandwidth of transmitted light is main relevant with reflectivity R, and reflectivity is higher, and (finesse) is less for frequency broadband or acutance.The feature of the transmitted spectrum of Fabry-Perot (Fabry-Perot) light standard tool is that the bandwidth of each transmission spectrum can be accomplished very narrow, the frequency interval of transmitted spectrum equates and the non-constant width of optical frequency bandwidth, generally can cover optical frequency bands of a spectrum more than 100 nanometers, as shown in Figure 9.
Because the general liquid crystal material as photoelectric device has high resistivity, therefore, can be considered to desirable dielectric substance.Owing to forming the orderly orientation of molecule and the form of extension elongation, liquid crystal has anisotropic dielectric characteristic and mono-symmetry, and as a uniaxial crystal, the direction of its optical axis is consistent with the oriented of molecule.When under the effect of liquid crystal molecule at external electrical field, can form electric dipole.Under the moment loading forming at electric dipole, make the orientation of liquid crystal molecule turn to the direction of electric field, can, by changing the power of electric field, change the direction of the optical axis of liquid crystal.Therefore, can utilize this characteristic of liquid crystal to make optical phase modulator, tunable optic filter or other photoelectric devices, as optical switch and light intensity modulator etc.The thickness of the general liquid crystal rete as photoelectric device is several microns to tens microns.The present invention utilizes just liquid crystal, under electric field action, the refractive index of linearly polarized light is produced to this characteristics design of change and forms.
Fig. 2 is the structural representation of a liquid crystal phase-modulator 200, comprises outer optically transparent material 12 and 24, transparent electrode layer 16 and 26, and separator 19 and liquid crystal layer 18. generally plate optical anti-reflective films in the inside and outside both side surface 5 and 7 of optically transparent material 12 and 24.Two transparency electrodes 16 of liquid crystal phase tuner are connected with drive circuit 14 with 26, the driving signal being produced by drive circuit forms and drives electric field between two transparency electrode retes, utilize the effective refractive index n of electric field change Fabry-Perot intraluminal fluid crystalline substance, regulate light frequency ν and the Free Spectral Range (FSR) of the transmitted light of fabry-perot filter.Fig. 3 has provided a thickness and has been about the nematic phase type liquid crystal of 10 microns at 2KHz, and amplitude peak is (as shown in Figure 4) under the driving of square-wave voltage of 5 volts of +/-, to optical wavelength be 1550 nanometer optical wave phase places change be related to schematic diagram.The maximum light phase that can realize approximately 2 π postpones.
It shown in Fig. 5, is the first structure of tunable fabry-perot filter, tunable fabry-perot filter 300 comprise the first band pass filter 10, liquid crystal phase-modulator 200, the second band pass filter 20 and drive circuit 14, the first band pass filters 10 and the second band pass filter 20 be respectively the outer surface 8 of optically transparent material 9 and 23 and 22 or inner surface 11 and 21 on plate multilayer dielectric film and realize.The first band pass filter 10 and the second band pass filter 20 have identical filtering characteristic, as shown in Figure 6, and at free transmission range ν
1with ν
2between (filtering interval 32), reflectivity is R, reflectivity is higher, transmitted spectrum approximately narrow (generally for optical communication, this reflectivity between 70% to 95%, for other application, as requested specially arrange), be less than ν
1(filtering interval 30) or be greater than ν
2(filtering interval 34) reflectivity is 100% or approaches 100%, and modern coating technique can accomplish to be greater than 100 nanometers this passband frequency spectrum scope.
The first Design of Bandpass scheme: as plated band pass filter multilayer dielectric film on the outer surface 8 and 22 at optically transparent material 9 and 23, the length in forming method Fabry-Perot-type (Fabry-Perot) chamber is D between two filters 10 and 20
1.The second Design of Bandpass scheme: as plated band pass filter multilayer dielectric film on the inner surface 11 and 21 at optically transparent material 9 and 23, the length in forming method Fabry-Perot-type (Fabry-Perot) chamber is D between two filters 10 and 20
2, obviously, due to D
1be greater than D
2.The Free Spectral Range of the fabry-perot filter that therefore, the first Design of Bandpass scheme can realize is less than the second design.Certainly, also can between the inner side of optically transparent material 12 and 24 and transparent electrode layer 16 and 26, directly plate multilayer thin-film-filter realizes, like this, due to the thickness very little (several microns to tens microns) of liquid crystal, therefore, can realize the larger tunable fabry-perot filter of intrinsic Free Spectral Range (i.e. the Free Spectral Range of the tunable optic filter when without extra electric field), but filter manufacture difficulty is larger.
Take above-mentioned the first Design of Bandpass scheme as example, in Fig. 5, the light beam 6 that incides filter 300 is a branch ofly to propagate along z direction, polarization axle is the linearly polarized light of x direction, identical with the optical axis direction of liquid crystal phase-modulator 200, the refractive index of supposing light transparent materials is n, at free transmission range ν
1with ν
2between, only have the 2nD of meeting
1the light of+Γ=m λ could see through etalon, and wherein m is the level time of transmitted light.The Free Spectral Range FSR of filter 300
2for: Δ λ=λ
2/ (2nD
1+ Γ), or with frequency representation:
?Δ ν=c/ (2nD
1+ Γ), wherein c is the light velocity, and Γ representative changes by refraction the light path that incident light is produced by liquid crystal under DC Electric Field, and the crest frequency of transmitted light can be expressed as: ν=mc/ (2nD
1+ Γ), wherein m is order of interference, transmission light frequency broadband can be expressed as:
Δ ν (FWHM)=c (1-R)/((2nD
1+ Γ) R
1/2), wherein c is the light velocity.
According to above-mentioned formula, tunable fabry-perot filter 300, for the linearly polarized light that approaches zero degree incident, is supposed n=1.5, D
1=1 millimeter, λ=1550 nanometer, the tuning range that can obtain the transmitted light crest frequency of about 150GHz (is about the intrinsic Free Spectral Range FSR of filter 300
21.5 times).Comparatively speaking, according to formula above, the change in the frequency band broadband to Free Spectral Range Δ ν and transmitted light is much smaller.The transmitted spectrum schematic diagram of tunable fabry-perot filter as shown in figure 10.
As can be seen here, tunable fabry-perot filter 300, under the effect of extra electric field, can be realized the tuning of transmitted light crest frequency in a big way and substantially not change transmission light frequency broadband and Free Spectral Range.This characteristic is for many application of tunable fabry-perot filter 300, as it is significant to be applied to laser and frequency spectrum instrument etc.Similarly, also can do identical analysis to the second Design of Bandpass scheme.At free transmission range ν
1with ν
2between spectrum region in addition 30 and 34, because the reflectivity of band pass filter 10 and 20 is 100% or approaches 100%, therefore, the filtered device 300 of this part incident light has stoped.
Can be found out by above analysis, as the intrinsic Free Spectral Range FSR of filter 300
2be greater than free transmission range ν
2-ν
1time, only have a mould to see through filter 300; Work as FSR
2be less than free transmission range ν
2-ν
1, and be greater than (the ν of 0.5 times
2-ν
1) time; only have 2 moulds to see through filter 300. therefore, after the free transmission range of the first band pass filter 10 and the second band pass filter 20 is determined, can be by intrinsic Free Spectral Range be set; realize in this free transmission range the single mode of filter 300 or 2 and 2 tunable outputs with patrix.Due to Fig. 6 demonstration is the filter characteristic of a desirable filter, in fact, above-mentioned band pass filter is between spectrum region 30 and 32, when 32 and 34 transition, can not a saltus step, but exist between a transition region, therefore, in the time that the free transmission range of the first band pass filter 10 and the second band pass filter 20 is set, also to consider above-mentioned factor.
For free transmission range ν
2-ν
1larger situation, as be greater than 50 nanometers, the manufacture difficulty of band pass filter 10 and band pass filter 20 is larger, particularly, as requires between spectrum region little situation between 30 and 32,32 and 34 transition region, and difficulty is larger.For this reason, designed the second structure of tunable fabry-perot filter: this structure adopts a kind of phase step type filter.This project organization has used two phase step type filters with different filter ranges to replace respectively the first band pass filter 10 and the second band pass filter 20.As shown in Figure 7, be a long-pass phase step type filter, light frequency is greater than ν
1light to have reflectivity be R, and light frequency is less than ν
1light to have reflectivity be 100% or approach 100%, replace band pass filter 10 with this long pass filter.Shown in Fig. 8 is a short-pass phase step type filter, and light frequency is less than ν
2light to have reflectivity be R, and light frequency is greater than ν
2light to have reflectivity be 100% or approach 100%, with this short bandpass filter replacement band pass filter 20, obviously, the structure of this use long-pass and short-pass phase step type filter is identical to the function of filter 300 with the design of above-mentioned use band pass filter.
This uses the advantage of the second structure of long-pass and short-pass phase step type filter to be: (1) relatively easily realizes large free transmission range (ν
2-ν
1), (2) relatively easily realize smaller from by the end of passband or the frequency spectrum transition from passband to rejection zone, because filter 300 has the invertibity of symmetry and light path, therefore, above-mentioned two phase step type filters are exchanged, do not affect the performance of filter 300.
Below the structure of external-cavity tunable laser of the present invention is elaborated.
A kind of tunable laser that adopts tunable fabry-perot filter 300, as shown in figure 11, the concrete structure of this tunable laser 400 is: comprise the laser cavity surface mirror 40 of installing successively, gain medium 42, collimating lens 43 in chamber, active optical phase modulator 44, tunable fabry-perot filter 300 and outgoing mirror 46, form laser resonant cavity by laser cavity surface mirror 40 and outgoing mirror 46, laser cavity speculum is the reflectivity difference to different wave length or color of light conventionally, here the reflectivity of mentioning is the reflectivity corresponding with the spectral bandwidth of laser operation.Laser cavity surface mirror 40 can, according to different situations, adopt total reflective mirror, or partially reflecting mirror.If when gain medium 42 is semiconductor gain media, owing to generally having larger output dispersion angle, therefore, in chamber, collimating lens 43 is generally to use while being semiconductor gain media for gain medium.When gain medium is gas, when liquid or some solid dielectric, generally without collimating lens in chamber, but the laser cavity surface mirror of employing on-plane surface chamber mirror and outgoing mirror 46 are to realize the reasonable layout of chamber inner light beam.
The light that in chamber, collimating lens 43 not only can send gain medium 42 plays collimating effect, is also the collimating lens of Laser Output Beam 48 simultaneously.For this class laser of optical-fibre communications, output beam 48 need to be coupled in optical fiber, collimating lens 43 is absolutely necessary.Meanwhile, it should be noted that, in the application of tunable laser of the present invention, what tunable fabry-perot filter 300 adopted is single-mode output, Figure 12 is the transmitted spectrum schematic diagram of tunable laser of the present invention.
In tunable laser 400, the broadband fluorescent light beam of being sent by gain medium 42 sees through active optical phase modulator 44 after collimating lens in chamber 43 collimates, again after tunable fabry-perot filter 300, in having formed laser resonant cavity by laser cavity surface mirror 40 and outgoing mirror 46, form laser resonance and amplification, in the time that the gain in chamber is greater than loss, form Laser output.Because the output light of semiconductor gain media is generally to have linear polarization characteristic, therefore, output light 48 is linearly polarized lights.The output light frequency of tunable laser 400 is tuning to be realized tuning by active optical phase modulator 44 and tunable fabry-perot filter 300.
What Figure 13 showed is the control system of tunable laser 400.Laser drives and control system comprises laser pumping source 50 and Laser Control System 56.By Laser Control System 56, to active phase-modulator drive source 52, laser pumping source 50 and filter drive source 14 are controlled.Select the light frequency of the chamber interior resonance film of tunable laser 400 by controlling filter drive source 14, the phase matched that regulates the phase place of chamber inner light beam to realize chamber interior resonance film by control source phase-modulator drive source 52 makes the mould of some specific light frequencies in laser cavity, produce laser generation and amplification.Due to active optical phase modulator 52, have very wide spectral range, therefore, the maximum output spectrum scope of tunable laser 400 is to be determined by the Free Spectral Range of tunable fabry-perot filter 300, in this spectral region, realize precise tunable.
Meanwhile, tunable fabry-perot filter 300 has also determined that tunable laser 400 exports the spectrum width of light.Adopt the tunable fabry-perot filter 300 of high sharpness coefficient can play the spectral bandwidth of compression output beam and improve side mode suppression ratio.By analysis above, because the bandwidth impact of the transmitted spectrum of tuning process on tunable fabry-perot filter 300 can be ignored, therefore, tunable laser 400 is in tuning process, and the bandwidth of output spectrum can be accomplished basically identical.
At present, in optical-fibre communications, conventional C frequency band (approximately 1530 nanometer-1570 nanometer) or the optical spectrum broadband of L frequency band (approximately 1570 nanometer-1610 nanometer) are about 40 nanometers, and tunable laser 400 can realize the fine tune within the scope of C frequency band and/or L frequency band completely.
It is emphasized that above-mentioned explanation only plays demonstration and describes, is not an in detail exhaustively explanation, is not intended to limit the present invention on described concrete form yet.Through description above, all may occur many changes of the present invention and variation.Selected concrete enforcement is only used to better explain the application in principle of the present invention and reality.This explanation can make the people who is familiar with this field can better utilize the present invention, designs according to actual needs different concrete enforcement and changes accordingly.
Claims (10)
1. one kind uses the tunable laser of tunable fabry-perot filter, comprise the laser cavity surface mirror of installing successively, gain medium, collimating lens in chamber, active optical phase modulator, tunable fabry-perot filter, outgoing mirror and laser drive and control system, form laser resonant cavity by described laser cavity surface mirror and outgoing mirror, described tunable fabry-perot filter comprises two kinds of designs: the first design comprises the first band pass filter of installing successively, liquid crystal phase-modulator, the second band pass filter and drive circuit, liquid crystal phase-modulator is arranged in the Fabry-Perot-type cavity being made up of the first band pass filter and the second band pass filter, drive circuit is realized the tuber function of filter by controlling the effective refractive index of liquid crystal material in described Fabry-Perot-type cavity, the second design comprises the long-pass phase step type filter of installing successively, liquid crystal phase-modulator, short-pass phase step type filter filtering device and drive circuit, liquid crystal phase-modulator is arranged in the Fabry-Perot-type cavity being made up of long-pass phase step type filter and short-pass phase step type filter, drive circuit is realized the tuber function of filter by controlling the effective refractive index of the liquid crystal material of liquid crystal phase-modulator in described Fabry-Perot-type cavity, the output tuning range of laser and tuning precision are determined by tuning range and the tuning precision of described tunable fabry-perot filter.
2. a kind of tunable laser according to claim 1, is characterized in that:
Described the first band pass filter and the second band pass filter are two band pass filters with identical transmission bandwidth, in transmission bandwidth, there is partial reflectance, this reflectivity has determined the transmitted light acutance of described tunable fabry-perot filter, different reflectivity can be set as required, for the application of optical-fibre communications, generally between 70% to 95%, have 100% or approach 100% reflectivity outward at transmission bandwidth.
3. a kind of tunable laser according to claim 1, is characterized in that:
Described long-pass phase step type filter has 100% or approach 100% reflectivity for the light that is less than cut-off frequency, there is partial reflectance for being greater than in the passband of cut-off frequency, described short-pass phase step type filter has 100% or approach 100% reflectivity for the light that is greater than cut-off frequency, there is partial reflectance for being less than in the passband of cut-off frequency, reflectivity in the passband of the reflectivity in the band of described long-pass phase step type filter and described short-pass phase step type filter is identical, this reflectivity has determined the transmitted light acutance of described tunable fabry-perot filter, different reflectivity can be set as required, reflectivity is higher, transmitted light acutance is higher, for the application of optical-fibre communications, generally between 70% to 95%, the cut-off frequency of described long-pass phase step type filter is less than the cut-off frequency of described short-pass phase step type filter.
4. a kind of tunable laser according to claim 1, is characterized in that:
Described the first band pass filter, described the second band pass filter, described long-pass phase step type filter and described short-pass phase step type filter are a kind of multilayer dielectric films of the plating of the medial surface at optically transparent material, at the outside of described optically transparent material plating optical anti-reflective film.
5. a kind of tunable laser according to claim 1, is characterized in that:
Described gain medium is a kind of broad band laser gain media.
6. a kind of tunable laser according to claim 1, is characterized in that:
Described laser drives and control system comprises active phase-modulator drive source and gain medium pumping source and system, control circuit, and the drive circuit of described liquid crystal phase-modulator is connected with described system, control circuit.
7. a kind of tunable laser according to claim 1, is characterized in that:
Described active optical phase modulator can be one of following several types: electro-optic phase modulator, acousto-optic phase-modulator, certain combination of magneto-optic phase-modulator or above-mentioned several phase-modulators.
8. a kind of tunable laser according to claim 1, it is characterized in that: the liquid crystal material in described liquid crystal phase-modulator is a kind of nematic phase type liquid crystal (nematic phase liquid crystal) material, thickness is several microns to tens microns, the linearly polarized light of a direction is there is the light phase delay of at least 2 π under the driving of extra electric field, and there is the spectral region identical with described gain medium.
9. a kind of tunable laser according to claim 1, is characterized in that:
The pass band width of described the first band pass filter and the second band pass filter is less than the Free Spectral Range of described tunable fabry-perot filter; After the combination of described long-pass phase step type filter and described short-pass phase step type filter, passband broadband is less than the Free Spectral Range of described tunable fabry-perot filter.
10. a kind of tunable laser according to claim 1, is characterized in that:
The drive circuit of described tunable fabry-perot filter is the square-wave pulse circuit that a kind of frequency is about 2 KHz, pulse voltage amplitude from 0 volt to positive and negative 5 volts adjustable.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210416719.4A CN103779777A (en) | 2012-10-28 | 2012-10-28 | Tunable laser using tunable fabry-perot filter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210416719.4A CN103779777A (en) | 2012-10-28 | 2012-10-28 | Tunable laser using tunable fabry-perot filter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN103779777A true CN103779777A (en) | 2014-05-07 |
Family
ID=50571752
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210416719.4A Pending CN103779777A (en) | 2012-10-28 | 2012-10-28 | Tunable laser using tunable fabry-perot filter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103779777A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106229807A (en) * | 2016-09-27 | 2016-12-14 | 中国科学技术大学 | A kind of laser pulse generator of CFS center frequency stabilization power amplification |
| CN106602398A (en) * | 2017-01-25 | 2017-04-26 | 中国科学院福建物质结构研究所 | Electro-optic Q-modulated tunable laser and method thereof, and laser medical equipment applying the laser |
| CN107247298A (en) * | 2017-07-06 | 2017-10-13 | 聊城大学 | A kind of medium film filter and YAG laser |
| CN110366699A (en) * | 2017-04-20 | 2019-10-22 | 松下知识产权经营株式会社 | Optical scanning device, optical receiving device and optical detection system |
| CN117353148B (en) * | 2023-10-07 | 2024-05-03 | 重庆大学 | Linear Fabry-Perot cavity optical feedback frequency locking device based on asymmetric cavity mirror reflectivity |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0545618A (en) * | 1991-02-04 | 1993-02-26 | Nippon Telegr & Teleph Corp <Ntt> | Variable wavelength filter |
| US5710655A (en) * | 1993-07-21 | 1998-01-20 | Apeldyn Corporation | Cavity thickness compensated etalon filter |
| US6545739B1 (en) * | 1997-09-19 | 2003-04-08 | Nippon Telegraph And Telephone Corporation | Tunable wavelength filter using nano-sized droplets of liquid crystal dispersed in a polymer |
| WO2005036241A1 (en) * | 2003-10-10 | 2005-04-21 | Shoei Kataoka | Wavelength variable filter and production method therefor |
| CN102244358A (en) * | 2011-06-02 | 2011-11-16 | 天津奇谱光电技术有限公司 | External-cavity tunable laser |
-
2012
- 2012-10-28 CN CN201210416719.4A patent/CN103779777A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0545618A (en) * | 1991-02-04 | 1993-02-26 | Nippon Telegr & Teleph Corp <Ntt> | Variable wavelength filter |
| US5710655A (en) * | 1993-07-21 | 1998-01-20 | Apeldyn Corporation | Cavity thickness compensated etalon filter |
| US6545739B1 (en) * | 1997-09-19 | 2003-04-08 | Nippon Telegraph And Telephone Corporation | Tunable wavelength filter using nano-sized droplets of liquid crystal dispersed in a polymer |
| WO2005036241A1 (en) * | 2003-10-10 | 2005-04-21 | Shoei Kataoka | Wavelength variable filter and production method therefor |
| CN102244358A (en) * | 2011-06-02 | 2011-11-16 | 天津奇谱光电技术有限公司 | External-cavity tunable laser |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106229807A (en) * | 2016-09-27 | 2016-12-14 | 中国科学技术大学 | A kind of laser pulse generator of CFS center frequency stabilization power amplification |
| CN106229807B (en) * | 2016-09-27 | 2019-07-23 | 中国科学技术大学 | A kind of laser pulse generation device of CFS center frequency stabilization power amplification |
| CN106602398A (en) * | 2017-01-25 | 2017-04-26 | 中国科学院福建物质结构研究所 | Electro-optic Q-modulated tunable laser and method thereof, and laser medical equipment applying the laser |
| CN110366699A (en) * | 2017-04-20 | 2019-10-22 | 松下知识产权经营株式会社 | Optical scanning device, optical receiving device and optical detection system |
| US20200003873A1 (en) * | 2017-04-20 | 2020-01-02 | Panasonic Intellectual Property Management Co., Ltd. | Optical scanning device, photoreceiver device, and photodetection system |
| US11644540B2 (en) * | 2017-04-20 | 2023-05-09 | Panasonic Intellectual Property Management Co., Ltd. | Optical scanning device, photoreceiver device, and photodetection system |
| CN110366699B (en) * | 2017-04-20 | 2023-09-22 | 松下知识产权经营株式会社 | Optical scanning device, optical receiving device, and optical detection system |
| CN107247298A (en) * | 2017-07-06 | 2017-10-13 | 聊城大学 | A kind of medium film filter and YAG laser |
| CN117353148B (en) * | 2023-10-07 | 2024-05-03 | 重庆大学 | Linear Fabry-Perot cavity optical feedback frequency locking device based on asymmetric cavity mirror reflectivity |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103762487B (en) | A kind of tunable laser with dual output light beam | |
| CN102709799B (en) | A kind of broadband continuous tunable frequency-stabilized laser | |
| CN102820611B (en) | Tunable laser for outputting non-polarized light | |
| CN103776530B (en) | A kind of spectral analysis apparatus using tunable fabry-perot filter | |
| CN101814694B (en) | Tunable laser | |
| CN103730826A (en) | Tunable laser system | |
| CN101794958A (en) | Tunable laser | |
| CN102799013A (en) | Polarization-irrelevant tunable Fabry-Perot filter | |
| CN102306900B (en) | External cavity broadband tunable laser with double gain mediums of polarization coupling | |
| WO2013007027A1 (en) | Optical frequency precision tunable laser | |
| CN102829870B (en) | Spectrum analytical equipment | |
| CN103779777A (en) | Tunable laser using tunable fabry-perot filter | |
| CN106772752A (en) | Based on MEMS tunable wave length FP optical fiber filters and preparation method thereof | |
| CN102798991B (en) | Tunable optical filter irrelevant to polarization state of incident light | |
| CN102332678B (en) | External cavity type broadband tunable laser coupling filter with double laser gain media | |
| CN102798987B (en) | Tunable optical filter with fixed frequency space and single-mode output | |
| CN103777381A (en) | Tunable narrowband optical filtering equipment with liquid crystal phase modulator | |
| US20120268709A1 (en) | Tunable optical filters with liquid crystal resonators | |
| CN103776791A (en) | Carbon monoxide gas sensing equipment | |
| CN102798998A (en) | Single-mode continuous tunable optical filter | |
| CN104166243A (en) | Unequal-bandwidth optical comb filter | |
| CN102955279A (en) | Tunable Fabry-Perot filter | |
| CN204086700U (en) | A kind of different-bandwidth optics comb filter | |
| CN103776799A (en) | Hydrogen sulfide gas sensing equipment | |
| CN103776794A (en) | Methane gas sensing equipment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20140507 |