WO2016169007A1 - 一种波长锁定器、波长锁定方法和装置 - Google Patents

一种波长锁定器、波长锁定方法和装置 Download PDF

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Publication number
WO2016169007A1
WO2016169007A1 PCT/CN2015/077192 CN2015077192W WO2016169007A1 WO 2016169007 A1 WO2016169007 A1 WO 2016169007A1 CN 2015077192 W CN2015077192 W CN 2015077192W WO 2016169007 A1 WO2016169007 A1 WO 2016169007A1
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Prior art keywords
optical signal
etalon
electrical signal
converted
laser
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PCT/CN2015/077192
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English (en)
French (fr)
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韦逸嘉
李良川
赵平
吴波
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华为技术有限公司
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Priority to CN201580079093.4A priority Critical patent/CN107534495B/zh
Priority to PCT/CN2015/077192 priority patent/WO2016169007A1/zh
Publication of WO2016169007A1 publication Critical patent/WO2016169007A1/zh

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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01SDEVICES 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
    • H01S5/00Semiconductor lasers
    • H01S5/06Arrangements for controlling the laser output parameters, e.g. by operating on the active medium
    • H01S5/068Stabilisation of laser output parameters
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01SDEVICES 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
    • H01S5/00Semiconductor lasers
    • H01S5/10Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region
    • H01S5/12Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region the resonator having a periodic structure, e.g. in distributed feedback [DFB] lasers
    • H01S5/125Distributed Bragg reflector [DBR] lasers
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B10/00Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/50Transmitters
    • H04B10/572Wavelength control

Definitions

  • the present invention relates to the field of communications technologies, and in particular, to a wavelength locker, a wavelength locking method, and a device.
  • a wavelength tunable laser is generally used as a transmitting laser with a wavelength interval of 50 GHz, if the laser wavelength of the transmitting end drifts. It may cause channel crosstalk and generate transmission cost. In this case, high requirements are placed on the laser wavelength stability. At present, the highest precision laser is biased throughout the life cycle, that is, from the end of the factory to the end of the service life. The maximum shift is no more than ⁇ 2.5G Hz.
  • each subband is only spaced about 2.5 GHz apart, the baud rate is greater than 2 Gbaud, if the frequency offset is greater than 1 GHz It may cause the transmission to fail. Even in the transceiver module of 10G network, a higher precision wavelength locking device is also required to prevent channel crosstalk.
  • the tunable lasers used in DWDM systems mainly include Distributed Bragg Reflector (DBR) lasers, Distributed Feedback (DFB) lasers, and External Cavity Lasers (ECL).
  • DBR Distributed Bragg Reflector
  • DFB Distributed Feedback
  • ECL External Cavity Lasers
  • the cost of ECL is relatively high, the DFB laser is relatively simple, and the cost of DBR laser is relatively low.
  • the principle of DBR laser is that the optical signal oscillating from the active region is filtered by Bragg grating to obtain the desired wavelength.
  • the digital mode-DS-DBR (Digital Supermode Distributed Bragg Reflector) laser can be controlled by multi-electrode structure, and a peak is selected from the sampled grating as the lasing wavelength, and the phase region is responsible for fine adjustment.
  • the front grating and the back grating reflection area are composed of chirped gratings, which provide comb-like reflection peaks. Through the different combinations of front and rear gratings, large-scale wavelength shift of C-band can be realized, and the active gain region can be realized.
  • the optical gain in the cavity is provided, and the phase region can slightly tune the optical frequency in the cavity.
  • I 1 , I 2 , I 3 , I 4 , I 5 , I 6 , I 7 , I 8 represent the front grating reflection area control pin current
  • I g represents the active gain area control pin current
  • I p represents The phase zone controls the pin current
  • I r represents the post-grating reflection zone control pin current.
  • the basic principle of the current wavelength locking scheme is to convert the wavelength information of the optical signal into amplitude information, so that the photodiode can be used for detection.
  • the key device for converting the wavelength information of an optical signal into amplitude information is called a wavelength locker.
  • the wavelength locker converts the wavelength information of the optical signal into a current signal output
  • the external circuit converts the current signal outputted by the external circuit into a voltage signal, monitors the temperature, voltage and other parameters of the laser according to the detected data, thereby controlling the output optical signal of the laser.
  • Wavelength the purpose of achieving a stable output wavelength.
  • FP etalon Fabry-Perot etalon
  • the interference filter can only be used for a specific wavelength
  • the FP etalon is a general-purpose optical device, consisting of a pair. It consists of flat glass plated with reflective film and parallel spacers. It is basically not affected by temperature and other circuits after packaging, which is good for maintaining the accuracy of detection information.
  • n is the refractive index of the flat glass in the FP etalon
  • l is the thickness of the flat glass
  • is the wavelength of the incident light
  • is the incident angle of the light beam
  • the light beam formed by superimposing the plurality of reflected light signals is converted by the photodiode into Current
  • a beam formed by superimposing a plurality of transmitted light signals is converted into a current by a photodiode
  • I t /I i varies with the wavelength of the incident light to form a comb filter as shown in FIG.
  • i E1 is The current formed by the transmitted light
  • i E2 is the current formed by the reflected light
  • I E is the current formed by the incident light
  • the peaks of the two comb filters, the valleys are symmetrical with each other, and the period between the peaks is called the free spectral region (FSR, free spectral) Range)
  • FSR free spectral region
  • c is the speed of light
  • n is the refractive index of the flat glass in the FP etalon
  • l is the thickness of the flat glass
  • is the incident angle of the beam
  • the comb filter The shape is represented by the sharpness formula: R is the reflectance of the flat glass in the FP etalon, and the larger the F, the steeper the shape of the comb filter.
  • the light beam reflected by the incident beam is converted into a current i E2 by a photodiode, and the light beam transmitted by the incident beam is converted into a current i E1 by another photodiode.
  • the ratio of the two currents is related to the wavelength of the incident light, and the change in the wavelength of the incident light can be judged by the change in the ratio of the two currents or the change in the difference.
  • the change of the current reflected by the same wavelength change is the largest and can be considered to be linear.
  • the laser When the laser is shipped from the factory, four stages of current values corresponding to different wavelengths are stored by means of a pre-built look-up table for tuning the International Telecommunication Union (ITU) wavelength.
  • ITU International Telecommunication Union
  • the period of the FP etalon can be designed to be equal to 50 GHz, and the transfer function of the FP etalon (ie, the curve shown in FIG. 2)
  • the intersection of the curve of i E1 and the curve of i E2 ie, the point with the largest slope in the curve of i E1 ) is aligned with the center wavelength of the ITU wavelength meter.
  • the wavelength of the light output by the laser at the factory is the ITU wavelength point
  • the DSP system records The current value of the FP etalon at that time, as time passes, when the wavelength of the light output by the laser is shifted, when the beam passes through the FP etalon, the change of the current value can be detected, and the DS-DBR is linearly adjusted.
  • the pin current of the laser produces a linear change in wavelength that causes the sense current to change linearly back to the factory-recorded current.
  • the periodicity of the transfer function of the F-P etalon causes the correct frequency offset to be undetectable.
  • the slope of each point on the transfer function of the FP etalon is different, as shown in Fig. 2, the A1 region between the peak and the trough is a linear region, and the A2 region near the peak tip is a nonlinear region when the wavelength shifts.
  • the same frequency offset corresponding to the change in current value will be smaller than the linear region, which will cause the accuracy of the measurement frequency offset to deteriorate, and the electrical signal of a certain system always has the maximum range and the minimum range, So even if there is an amplifier behind it, it can linearly amplify the current change when the frequency shifts to the A2 area. This may cause the current variation value to exceed the reasonable range such as the ADC input voltage range due to the frequency shift to the A1 region. Therefore, the locking accuracy of the current wavelength locking scheme is limited by the frequency offset value. High precision in the full band range.
  • the current wavelength locking scheme cannot detect the correct frequency offset when the wavelength drift exceeds one cycle of the transfer function of the FP etalon; and the locking accuracy of the current wavelength locking scheme is limited by the frequency offset value.
  • the size cannot be achieved with high precision in the full band range.
  • the embodiment of the invention provides a wavelength locker, a wavelength locking method and a device, which are used to solve the problem that the existing wavelength locking scheme cannot detect the correct frequency offset when the frequency drift exceeds one cycle of the transmission function of the FP etalon. And the locking accuracy is limited by the magnitude of the frequency offset value, and high precision in the full band range cannot be achieved.
  • a wavelength locker including a coupler, a first Fabry-Perot F-P etalon, a second F-P etalon, and a detection processing circuit;
  • the coupler is configured to split the received optical signal into two optical signals, and the optical signal received by the coupler is a light signal after the optical signal emitted by the laser passes through the splitting;
  • the first FP etalon for reflecting and refracting a bundle of optical signals divided by the coupler; a maximum frequency and a minimum frequency of a linear region in one cycle of a transfer function of the first FP etalon The difference is not greater than the minimum detection accuracy of the demand;
  • the second FP etalon is configured to reflect and refract another optical signal divided by the coupler; a period length of a transfer function of the second FP etalon is not less than a frequency offset of the laser Two times the maximum value; the frequency of the optical signal of the preset wavelength of the laser is located in a linear region of the transfer function of the first FP etalon and is located in a linear region of the transfer function of the second FP etalon;
  • the detection processing circuit is configured to adjust a tube of the laser according to the optical signal and the transmitted optical signal reflected by the first FP etalon, and the optical signal and the transmitted optical signal reflected by the second FP etalon
  • the foot current causes the frequency offset of the laser to be within the error range.
  • a period length of a transfer function of the second F-P etalon is a positive integer multiple of a period length of a transfer function of the first F-P etalon.
  • the transmission function of the second FP etalon is a peak at the first frequency
  • the first FP etalon The transfer function is also a peak at the first frequency.
  • the difference between the maximum frequency and the minimum frequency of the linear region in one cycle of the transfer function of the first F-P etalon is equal to the minimum detection accuracy of the requirement.
  • the detection processing circuit is specifically configured to:
  • the pin current of the laser is such that the difference between the comparison result of the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal does not exceed the second threshold value;
  • the frequency offset of the laser when the difference between the comparison between the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal does not exceed the second threshold within the error range;
  • the first pre-stored value is a comparison result of an electrical signal converted by the optical signal reflected by the second FP etalon and an electrical signal converted by the transmitted optical signal when the laser emits an optical signal of a preset wavelength
  • the second pre-stored value is a comparison result of the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal when the laser emits an optical signal of a preset wavelength.
  • the comparison between the electrical signal converted by the optical signal reflected by the second FP etalon and the electrical signal converted by the transmitted optical signal is the conversion of the electrical signal and the transmitted optical signal converted by the optical signal reflected by the second FP etalon The difference of the electrical signal;
  • the first pre-stored value is a difference between an electrical signal converted by the optical signal reflected by the second F-P etalon and an electrical signal converted by the transmitted optical signal when the laser emits an optical signal of a predetermined wavelength.
  • a comparison result between the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal a difference between an electrical signal converted by the optical signal reflected by the first FP etalon and an electrical signal converted by the transmitted optical signal;
  • the second pre-stored value is a difference between an electrical signal converted by the optical signal reflected by the first F-P etalon and an electrical signal converted by the transmitted optical signal when the laser emits an optical signal of a preset wavelength.
  • a wavelength locking method including:
  • the first FP etalon reflects and refracts a light signal divided by the coupler; the coupler is configured to split the optical signal emitted by the laser into two optical signals after splitting the optical signal; The difference between the maximum frequency and the minimum frequency of the linear region in one cycle of the transfer function of the first FP etalon is not greater than the minimum detection accuracy required; the second FP etamer divides the other light into the coupler The signal is reflected and refracted; the period length of the transfer function of the second FP etalon is not less than twice the maximum value of the frequency offset of the laser; the frequency of the optical signal of the preset wavelength of the laser is located at A linear region of the transfer function of the first FP etalon and located in a linear region of the transfer function of the second FP etalon.
  • the optical signal and the transmitted optical signal reflected by the first F-P etalon, and the optical signal reflected by the second F-P etalon adjusts the pin current of the laser such that the frequency offset of the laser is within an error range, and specifically includes:
  • the pin current of the laser is such that the difference between the comparison result of the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal does not exceed the second threshold value;
  • the frequency offset of the laser when the difference between the comparison between the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal does not exceed the second threshold within the error range;
  • the first pre-stored value is a comparison result of an electrical signal converted by the optical signal reflected by the second FP etalon and an electrical signal converted by the transmitted optical signal when the laser emits an optical signal of a preset wavelength
  • the second pre-stored value is a comparison result of the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal when the laser emits an optical signal of a preset wavelength.
  • a comparison result between the electrical signal converted by the optical signal reflected by the second FP etalon and the electrical signal converted by the transmitted optical signal a difference between an electrical signal converted by the optical signal reflected by the second FP etalon and an electrical signal converted by the transmitted optical signal;
  • the first pre-stored value is a difference between an electrical signal converted by the optical signal reflected by the second F-P etalon and an electrical signal converted by the transmitted optical signal when the laser emits an optical signal of a predetermined wavelength.
  • a comparison result between the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal Is an electrical signal converted by the optical signal reflected by the first FP etalon and transmitted The difference between the electrical signals converted by the optical signal;
  • the second pre-stored value is a difference between an electrical signal converted by the optical signal reflected by the first F-P etalon and an electrical signal converted by the transmitted optical signal when the laser emits an optical signal of a preset wavelength.
  • a period length of a transfer function of the second F-P etalon is a positive integer multiple of a period length of a transfer function of the first F-P etalon.
  • the transmission function of the second FP etalon is a peak at the first frequency
  • the first FP etalon The transfer function is also a peak at the first frequency.
  • the difference between the maximum frequency and the minimum frequency of the linear region in one cycle of the transfer function of the first F-P etalon is equal to the minimum detection accuracy of the requirement.
  • a wavelength locking device comprising:
  • An acquiring module configured to obtain an optical signal and a transmitted optical signal reflected by the first F-P etalon, and obtain an optical signal and a transmitted optical signal reflected by the second F-P etalon;
  • an adjusting module configured to adjust a pin current of the laser according to the optical signal and the transmitted optical signal reflected by the first FP etalon, and the optical signal and the transmitted optical signal reflected by the second FP etalon, Causing the frequency of the laser to be within an error range;
  • the first FP etalon reflects and refracts a bundle of optical signals split by the coupler; the coupler splits the optical signal emitted by the laser into two optical signals after splitting; The difference between the maximum frequency and the minimum frequency of the linear region in one cycle of the transfer function of the first FP etalon is not greater than the minimum detection accuracy required; the second FP etalon splits the other optical signal into the coupler Performing reflection and refraction; the period length of the transfer function of the second FP etalon is not less than twice the maximum value of the frequency offset of the laser; the frequency of the optical signal of the preset wavelength of the laser is located at the A linear region of the transfer function of an FP etalon and located in a linear region of the transfer function of the second FP etalon.
  • the adjusting module is specifically configured to:
  • An electrical signal converted by the optical signal reflected by the second F-P etalon and a transmitted optical signal The difference between the comparison result of the electrical signal and the first pre-stored value and the set wavelength of the laser output optical signal, adjusting the pin current of the laser such that the optical signal reflected by the second FP etalon is converted
  • the difference between the comparison result of the electrical signal converted by the signal and the transmitted optical signal and the first pre-stored value does not exceed the first threshold;
  • the pin current of the laser is such that the difference between the comparison result of the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal does not exceed the second threshold value;
  • the frequency offset of the laser when the difference between the comparison between the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal does not exceed the second threshold within the error range;
  • the first pre-stored value is a comparison result of an electrical signal converted by the optical signal reflected by the second FP etalon and an electrical signal converted by the transmitted optical signal when the laser emits an optical signal of a preset wavelength
  • the second pre-stored value is a comparison result of the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal when the laser emits an optical signal of a preset wavelength.
  • a comparison result between the electrical signal converted by the optical signal reflected by the second FP etalon and the electrical signal converted by the transmitted optical signal a difference between an electrical signal converted by the optical signal reflected by the second FP etalon and an electrical signal converted by the transmitted optical signal;
  • the first pre-stored value is a difference between an electrical signal converted by the optical signal reflected by the second F-P etalon and an electrical signal converted by the transmitted optical signal when the laser emits an optical signal of a predetermined wavelength.
  • a comparison result between the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal a difference between an electrical signal converted by the optical signal reflected by the first FP etalon and an electrical signal converted by the transmitted optical signal;
  • the second pre-stored value is a difference between an electrical signal converted by the optical signal reflected by the first F-P etalon and an electrical signal converted by the transmitted optical signal when the laser emits an optical signal of a preset wavelength.
  • the laser since the period length of the transfer function of the second FP etalon is not less than twice the maximum value of the frequency offset of the laser, the laser emits The wavelength of the optical signal does not shift by more than half of one cycle of the transfer function of the FP etalon.
  • the detection processing circuit can correctly detect the offset of the wavelength of the optical signal emitted by the laser, thereby adjusting the pin current of the laser so that the laser emits The wavelength of the optical signal is close to the preset wavelength.
  • the frequency is located in a linear region of the transfer function of the first FP etalon, and since the difference between the maximum frequency and the minimum frequency of the linear region in one cycle of the transfer function of the first FP etalon is not greater than the minimum detection accuracy of the demand,
  • the detection processing circuit can measure the offset of the wavelength of the optical signal emitted by the laser with a minimum detection accuracy of no more than the demand, thereby adjusting the pin current of the laser such that the frequency offset of the laser is within the error range. Therefore, after the first F-P etalon is used in combination with the second F-P etalon, the detection processing circuit can achieve high-precision detection and locking in the full-band range.
  • FIG. 1 is a schematic diagram of a model of a DS-DBR tunable laser in the prior art
  • FIG. 2 is a graph showing a curve of a current converted by an optical signal transmitted by an F-P etalon according to a frequency of an optical signal and a current converted by the reflected optical signal as a function of a frequency of the optical signal;
  • FIG. 3 is a schematic structural diagram of a wavelength locker according to an embodiment of the present invention.
  • FIG. 4 is a second schematic structural diagram of a wavelength locker according to an embodiment of the present invention.
  • FIG. 5 is a curve of a transfer function of a first F-P etalon and a transfer function of a second F-P etalon in a wavelength locker according to an embodiment of the present invention
  • FIG. 6 is a flowchart of a wavelength locking method according to an embodiment of the present disclosure.
  • FIG. 7 is a second flowchart of a wavelength locking method according to an embodiment of the present disclosure.
  • FIG. 8 is a flowchart of a wavelength locking method according to an embodiment of the present invention applied in practice
  • FIG. 9 is a structural diagram of a wavelength locking device according to an embodiment of the present invention.
  • a wavelength locker, a wavelength locking method and a device are provided by the second embodiment of the present invention, and the second FP etalon and the detection processing circuit realize the correct detection of the frequency offset and realize the coarse adjustment of the wavelength of the optical signal emitted by the laser.
  • the first FP etalon and the detection processing circuit realize high-precision detection of the frequency offset and realize high-precision locking of the wavelength of the optical signal emitted by the laser.
  • the wavelength locker provided by the embodiment of the present invention includes a coupler 31, a first Fabry-Perot F-P etalon 32, a second F-P etalon 33, and a detection processing circuit 34;
  • the coupler 31 is configured to split the received optical signal into two optical signals, and the optical signal received by the coupler 31 is a light signal after the optical signal emitted by the laser 35 is split;
  • a first FP etalon 32 for reflecting and refracting a beam of light split by the coupler 31; a difference between a maximum frequency and a minimum frequency of a linear region in one cycle of the transfer function of the first FP etalon 32 is not greater than Minimum detection accuracy of demand;
  • a second FP etalon 33 for reflecting and refracting another optical signal split by the coupler 31;
  • the period length of the transfer function of the second FP etalon 33 is not less than two of the maximum values of the frequency offset of the laser 35
  • the frequency of the optical signal of the preset wavelength of the laser 35 is located in a linear region of the transfer function of the first FP etalon 32 and is located in a linear region of the transfer function of the second FP etalon 33;
  • the detection processing circuit 34 is configured to adjust the pin current of the laser 35 according to the optical signal and the transmitted optical signal reflected by the first FP etalon 32, and the optical signal and the transmitted optical signal reflected by the second FP etalon 33, so that the pin current of the laser 35 is adjusted.
  • the frequency offset of the laser 35 is within the error range.
  • the wavelength locker provided by the embodiment of the present invention may adopt the structure described in FIG. 4, wherein the detection processing circuit includes four photodiodes 41 and four first transversals.
  • P.I.D. proportional integral derivative
  • DSP digital signal processing
  • the laser 35 outputs an optical signal having a wavelength of ⁇ 0 and a power of P 0 , and the voltage signal entering the PID control unit is:
  • V E11 ( ⁇ ) ⁇ 1 ⁇ 2 P 0 R E11 A 11 T E1 ( ⁇ );
  • V E12 ( ⁇ ) ⁇ 1 ⁇ 2 P 0 R E12 A 12 (1-T E1 ( ⁇ ));
  • V E21 ( ⁇ ) ⁇ 1 ⁇ 2 P 0 R E21 A 21 T E2 ( ⁇ );
  • V E22 ( ⁇ ) ⁇ 1 ⁇ 2 P 0 R E22 A 22 (1-T E2 ( ⁇ ));
  • ⁇ 1 is the laser 35 emitted light signals sent spectrally splitting ratio of the coupler
  • ⁇ 2 is the splitting ratio of coupler 31
  • R E11 R E12 R E21 R E22 are respectively four photodiodes responsivity
  • a 11 A 12 A 21 A 22 are the amplification factors of the four transimpedance amplifiers respectively
  • T E1 is the transfer function of the first FP etalon
  • T E2 is the transfer function of the second FP etalon:
  • T E1 ( ⁇ ) [1+F E1 sin 2 ( ⁇ / ⁇ fine )];
  • T E2 ( ⁇ ) [1+F E2 sin 2 ( ⁇ / ⁇ corase )];
  • F E1 is the sharpness of the first FP etalon
  • F E2 is the sharpness of the second FP etalon
  • ⁇ fine is the FSR of the first FP etalon
  • ⁇ corase is the FSR of the second FP etalon.
  • the period and phase of the transfer function of the FP etalon depends on the wavelength, angle, plate spacing, and plate material reflectivity of the incident light
  • the incident light of the first FP etalon and the second FP etalon has the same wavelength
  • the incident light with the same angle materials with different plate spacing and different reflectivity can be used to design two FP etalons with full cycle and phase of the transfer function.
  • the period length of the transfer function of the second F-P etalon is a positive integer multiple of the period length of the transfer function of the first F-P etalon. So when the laser is a tunable laser, The wavelength of each of the transmittable optical signals set by the optical device at the factory can be located both in the linear region of the transfer function of the first F-P etalon and in the linear region of the transfer function of the second etalon.
  • the transfer function of the second F-P etalon is a peak at the first frequency
  • the transfer function of the first F-P etalon is also a peak at the first frequency. That is, the position of the peak of the transfer function of the second FP etalon overlaps with the position of a part of the peak of the transfer function of the first FP etalon, so that the frequency of the optical signal of the preset wavelength of the laser is ensured to be A linear region of the transfer function of the first FP etalon and located in a linear region of the transfer function of the second FP etalon.
  • the difference between the maximum frequency and the minimum frequency of the linear region in one cycle of the transfer function of the first F-P etalon is equal to the minimum detection accuracy of the requirement.
  • the detection processing circuit in the wavelength locker is specifically configured to: compare a result of an electrical signal converted by the optical signal reflected by the optical signal reflected by the second FP etalon and an electrical signal converted by the transmitted optical signal. And a difference between the first pre-stored value and the set wavelength of the laser output optical signal, adjusting a pin current of the laser, so that the electrical signal converted by the optical signal reflected by the second FP etalon and the transmitted optical signal are converted The difference between the comparison result of the electrical signal and the first pre-stored value does not exceed the first threshold;
  • the first pre-stored value is a comparison result of an electrical signal converted by the optical signal reflected by the second FP etalon and an electrical signal converted by the transmitted optical signal when the laser emits an optical signal of a preset wavelength
  • the second pre-stored value is a comparison result of the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal when the laser emits an optical signal of a preset wavelength.
  • the difference between the comparison result of the electrical signal converted by the optical signal reflected by the second F-P etalon and the electrical signal converted by the transmitted optical signal and the first pre-stored value does not exceed the first threshold, and the first F-P etalon is reversed
  • the wavelength of the optical signal emitted by the laser is within the error range when the difference between the comparison between the electrical signal converted by the transmitted optical signal and the electrical signal converted by the transmitted optical signal does not exceed the second threshold.
  • the comparison result of the electrical signal converted by the optical signal reflected by the second FP etalon and the electrical signal converted by the transmitted optical signal may be converted by the electrical signal converted by the optical signal reflected by the second FP etalon and transmitted by the transmitted optical signal.
  • the difference between the electrical signals may also be the ratio of the electrical signal converted by the optical signal reflected by the second FP etalon to the electrical signal converted by the transmitted optical signal.
  • the first pre-stored value is the difference between the electrical signal converted by the optical signal reflected by the second FP etalon and the electrical signal converted by the transmitted optical signal when the laser outputs the optical signal of the set wavelength.
  • the first pre-stored value is the ratio of the electrical signal converted by the optical signal reflected by the second FP etalon to the electrical signal converted by the transmitted optical signal when the laser outputs the optical signal of the set wavelength.
  • the comparison result of the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal may be converted by the electrical signal converted by the optical signal reflected by the first FP etalon and the transmitted optical signal.
  • the difference between the electrical signals may also be the ratio of the electrical signal converted by the optical signal reflected by the first FP etalon to the electrical signal converted by the transmitted optical signal.
  • the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal are compared, the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal
  • the second pre-stored value is the difference between the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal when the laser outputs the optical signal of the set wavelength.
  • the second pre-stored value is the ratio of the electrical signal converted by the optical signal reflected by the first FP etalon to the electrical signal converted by the transmitted optical signal when the laser outputs the optical signal of the set wavelength.
  • the preset wavelength is the wavelength of the optical signal emitted by the laser set at the factory, the laser
  • the product of the wavelength of the emitted optical signal and the frequency of the optical signal is equal to the speed of light. Therefore, when the frequency of the optical signal emitted by the laser is shifted, it means that the wavelength of the optical signal emitted by the laser deviates from the preset wavelength. Since the transfer function of the first F-P etalon is different from the transfer function of the second F-P etalon, the same frequency offset is different for the current converted by the optical signal reflected and transmitted by the different F-P etalon.
  • two FP etalons of the transfer function of the curve shown in Figure 5 can be used to detect and lock the optical signal emitted by the laser.
  • the wavelength Assume that the frequency corresponding to the preset wavelength is 192.1125 THz (ie, q1 point).
  • the laser emits the optical signal of the wavelength through instrument calibration (assuming that the laser has no frequency offset in the initial stage of the life cycle).
  • the voltage generated by the first FP etalon and the second FP etalon is saved as Ve1 and Ve2, and the voltage value VR/VP/VG/VG of the pin currently transmitted from the DSP to the laser control laser is recorded.
  • the detection processing circuit is transmitted and reflected by the second FP etalon.
  • the optical signal obtains the voltage VE2 after the wavelength drifts, and the voltage VE2 after the wavelength drifts and the voltage Ve2 of the optical signal transmitted and reflected by the second FP etalon at the preset wavelength (ie, the first pre-stored value) can be
  • the second FP etalon (solid line in Figure 5) uniquely determines a point p1, which compares the difference between VE2 and Ve2 to coarsely adjust the amount of current applied to the tunable laser pin (front/rear).
  • VE2 is close to Ve2.
  • the corresponding point of VE2 on the transfer function of the second FP etalon is q2, and the wavelength of q2 point is in the transfer function of the first FP etalon (
  • the voltage on the dotted line in FIG. 5 is VE1, and VE1 can be applied to the tunable laser pin after comparing VE1 with Ve1 (ie, the second pre-stored value) of the optical signal transmitted and reflected by the first FP etalon at a predetermined wavelength.
  • the current is fine-tuned to make the VE1 connected Ve1, and when adjusted to Ve1 VE1 difference does not exceed a certain threshold, the signal may be considered a wavelength of light emitted by the laser is already in the error range, to complete the wavelength locking.
  • a wavelength locking method provided by an embodiment of the present invention, as shown in FIG. 6, includes:
  • the first FP etalon reflects and refracts a bundle of optical signals split by the coupler; the coupler splits the optical signal emitted by the laser into two optical signals after splitting; The difference between the maximum frequency and the minimum frequency of the linear region in one cycle of the transfer function of the first FP etalon is not greater than the minimum detection accuracy required; the second FP etalon splits the other optical signal into the coupler Performing reflection and refraction; the period length of the transfer function of the second FP etalon is not less than twice the maximum value of the frequency offset of the laser; the frequency of the optical signal of the preset wavelength of the laser is located at the A linear region of the transfer function of an FP etalon and located in a linear region of the transfer function of the second FP etalon.
  • S602 specifically includes:
  • the first pre-stored value is an optical signal when the laser emits a preset wavelength
  • the second F-P a comparison result of the electrical signal converted by the optical signal reflected by the etalon and the electrical signal converted by the transmitted optical signal
  • the second pre-stored value is the light reflected by the first FP etalon when the laser emits the optical signal of the preset wavelength
  • the coarse adjustment ie, S701
  • the coarse adjustment may have to obtain the comparison result of the electrical signal converted by the optical signal reflected by the second FP etalon and the electrical signal converted by the transmitted optical signal more than once, compared with the first pre-stored value, and Adjusting the pin current of the laser such that the difference between the comparison result of the electrical signal converted by the optical signal reflected by the second FP etalon and the converted electrical signal and the first pre-stored value does not exceed the first threshold;
  • fine tuning S702 may also be performed by comparing the electrical signal converted by the optical signal reflected by the first FP etalon with the electrical signal converted by the transmitted optical signal, comparing with the second pre-stored value, and adjusting the laser.
  • the pin current can complete the wavelength lock.
  • the wavelength of the optical signal emitted by the laser may be in the linear region of the FP etalon, or in the nonlinear region of the FP etalon, in the nonlinear region. It is necessary to compare the comparison between the electrical signal converted by the optical signal reflected by the FP etalon and the electrical signal converted by the transmitted optical signal before and after the adjustment of the laser pin voltage to determine the direction of the wavelength shift of the optical signal emitted by the laser, thereby completing the wavelength locking. .
  • the comparison result of the electrical signal converted by the optical signal reflected by the second FP etalon and the electrical signal converted by the transmitted optical signal may be converted by the electrical signal converted by the optical signal reflected by the second FP etalon and transmitted by the transmitted optical signal.
  • the difference between the electrical signals may also be the ratio of the electrical signal converted by the optical signal reflected by the second FP etalon to the electrical signal converted by the transmitted optical signal.
  • the first pre-stored value is the difference between the electrical signal converted by the optical signal reflected by the second FP etalon and the electrical signal converted by the transmitted optical signal when the laser outputs the optical signal of the set wavelength.
  • the first pre-stored value is the ratio of the electrical signal converted by the optical signal reflected by the second FP etalon to the electrical signal converted by the transmitted optical signal when the laser outputs the optical signal of the set wavelength.
  • the comparison result of the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal may be converted by the electrical signal converted by the optical signal reflected by the first FP etalon and the transmitted optical signal.
  • the difference between the electrical signals may also be the ratio of the electrical signal converted by the optical signal reflected by the first FP etalon to the electrical signal converted by the transmitted optical signal.
  • the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal are compared, the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal
  • the second pre-stored value is the difference between the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal when the laser outputs the optical signal of the set wavelength.
  • the second pre-stored value is the ratio of the electrical signal converted by the optical signal reflected by the first FP etalon to the electrical signal converted by the transmitted optical signal when the laser outputs the optical signal of the set wavelength.
  • the period length of the transfer function of the second F-P etalon is a positive integer multiple of the period length of the transfer function of the first F-P etalon.
  • the transfer function of the second F-P etalon is a peak at the first frequency
  • the transfer function of the first F-P etalon is also a peak at the first frequency
  • the difference between the maximum frequency and the minimum frequency of the linear region in one cycle of the transfer function of the first F-P etalon is equal to the minimum detection accuracy of the requirement.
  • FIG. 8 is a flowchart of a wavelength locking method applied in an actual embodiment according to an embodiment of the present invention, including:
  • S802. Determine, according to the optical signal reflected by the first FP etalon and the transmitted optical signal, a comparison result between the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal, and according to the second FP standard.
  • the reflected optical signal and the transmitted optical signal determine a comparison result of the electrical signal converted by the optical signal reflected by the second FP etalon and the electrical signal converted by the transmitted optical signal;
  • the electrical signal and the transmitted optical signal converted according to the optical signal reflected by the second F-P etalon Determining the direction (ie, increasing or decreasing) and size of the laser pin current adjustment and adjusting the laser pin current by comparing the difference between the converted electrical signal and the first pre-stored value, and the preset wavelength;
  • S805. Determine a direction of the laser pin current adjustment according to a difference between a comparison result of the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal, and a preset wavelength. That is, increase or decrease) and size, and adjust the laser pin current;
  • S806 Determine whether a difference between a comparison result of the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal is less than a second threshold. If yes, execute S807; otherwise, Execute S805;
  • the wavelength locking is completed, that is, the wavelength of the optical signal emitted by the laser is within the error range.
  • the embodiment of the present invention further provides a wavelength locking device. Since the principle of solving the problem is similar to the foregoing wavelength locking method, the implementation of the device can be referred to the implementation of the foregoing method, and the repetition is no longer Narration.
  • the wavelength locking device provided by the embodiment of the present invention, as shown in FIG. 9, includes:
  • the obtaining module 91 is configured to acquire the optical signal and the transmitted optical signal reflected by the first F-P etalon, and acquire the optical signal and the transmitted optical signal reflected by the second F-P etalon;
  • the adjusting module 92 is configured to adjust a pin current of the laser according to the optical signal and the transmitted optical signal reflected by the first FP etalon, and the optical signal and the transmitted optical signal reflected by the second FP etalon So that the frequency of the laser is shifted within the error range;
  • the first FP etalon reflects and refracts a bundle of optical signals split by the coupler; the coupler splits the optical signal emitted by the laser into two optical signals after splitting; The difference between the maximum frequency and the minimum frequency of the linear region in one cycle of the transfer function of the first FP etalon is not greater than the minimum detection accuracy required; the second FP etalon splits the other optical signal into the coupler Performing reflection and refraction; the period length of the transfer function of the second FP etalon is not less than twice the maximum value of the frequency offset of the laser; the preset of the laser
  • the frequency of the optical signal of the wavelength is located in a linear region of the transfer function of the first F-P etalon and in a linear region of the transfer function of the second F-P etalon.
  • the adjustment module 92 is specifically configured to:
  • the pin current of the laser is such that the difference between the comparison result of the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal does not exceed the second threshold value;
  • the frequency offset of the laser when the difference between the comparison between the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal does not exceed the second threshold within the error range;
  • the first pre-stored value is a comparison result of an electrical signal converted by the optical signal reflected by the second FP etalon and an electrical signal converted by the transmitted optical signal when the laser emits an optical signal of a preset wavelength
  • the second pre-stored value is a comparison result of the electrical signal converted by the optical signal reflected by the first FP etalon and the electrical signal converted by the transmitted optical signal when the laser emits an optical signal of a preset wavelength.
  • embodiments of the present invention can be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or a combination of software and hardware. Moreover, the invention can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) including computer usable program code.
  • computer-usable storage media including but not limited to disk storage, CD-ROM, optical storage, etc.
  • the computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture comprising the instruction device.
  • the apparatus implements the functions specified in one or more blocks of a flow or a flow and/or block diagram of the flowchart.
  • These computer program instructions can also be loaded onto a computer or other programmable data processing device such that a series of operational steps are performed on a computer or other programmable device to produce computer-implemented processing for execution on a computer or other programmable device.
  • the instructions provide steps for implementing the functions specified in one or more of the flow or in a block or blocks of a flow diagram.

Abstract

本发明实施例提供一种波长锁定器、波长锁定方法和装置,用以解决目前在波长漂移较大时,无法检测到正确的频率偏移,并且不能做到全波段范围内的高精度。该波长锁定器中的检测处理电路,用于根据所述第一F-P标准具反射和透射的光信号,以及所述第二F-P标准具反射和透射的光信号,调整所述激光器的管脚电流,使得所述激光器的频率偏移在误差范围内;所述第一F-P标准具的传输函数的一个周期内的线性区域的频率范围不大于需求的最小检测精度;所述第二F-P标准具的传输函数的周期长度不小于所述激光器的频率偏移的最大值的两倍;所述预设波长的光信号的频率位于所述第一F-P标准具的传输函数以及第二F-P标准具的传输函数的线性区域。

Description

一种波长锁定器、波长锁定方法和装置 技术领域
本发明涉及通信技术领域,特别涉及一种波长锁定器、波长锁定方法和装置。
背景技术
在目前的密集型光波复用(DWDM,Dense Wavelength Division Multiplexing)传输网络中,为了通用性,一般会使用波长可调谐的激光器来作为发射端激光器,波长间隔为50GHz,如果发射端的激光器波长发生漂移,可能导致通道串扰,产生传输代价,在这种情况下,对激光器波长稳定度提出了很高的要求,目前精度最高的激光器在整个生命周期,即从出厂到使用年限的终点过程中频率偏移最大值不超过±2.5G Hz。如果应用在波长间隔和波特率更低的系统中,例如未来的超级子载波(super-subcarrier)系统中,每个子带只间隔大约2.5GHz,波特率大于2Gbaud,如果频率偏移大于1GHz就可能导致传输失败。甚至在万兆网的收发一体模块中,同样也需要更高精度的波长锁定装置来防止通道串扰。
用于DWDM系统的可调谐激光器主要有分布式布拉格反射(DBR,Distributed Bragg Reflector)激光器、分布式反馈(DFB,Distributed Feedback)激光器、外腔激光器(ECL,External Cavity Laser)等几种类型,其中ECL成本较高,DFB激光器较为简单,DBR激光器成本较低,目前是可调谐激光器的主流技术,DBR激光器的原理是从有源区起振的光信号经过布拉格光栅的筛选后得到所需波长,数字模式-分布式布拉格反射(DS-DBR,Digital Supermode Distributed Bragg Reflector)激光器可以通过多电极结构寻址控制,从取样光栅中选取一个峰作为激射波长,相位区负责细微调整。其结构如图1所示,其中前光栅和后光栅反射区由啁啾光栅构成,提供梳状的反射峰,通过前后光栅不同的组合,可以实现C波段的大尺度波长移动,有源增益区提 供谐振腔内光增益,相位区可以对谐振腔内光频率进行微小调谐。其中,I1、I2、I3,I4,I5、I6、I7,I8表示前光栅反射区控制管脚电流,Ig表示有源增益区控制管脚电流,Ip表示相位区控制管脚电流,Ir表示后光栅反射区控制管脚电流。
目前的波长锁定方案的基本原理是将光信号的波长信息转换成为幅度信息,从而可以使用光电二极管进行检测。这里将光信号的波长信息转换成为幅度信息的关键器件被称之为波长锁定器。波长锁定器将光信号的波长信息转换成为电流信号输出,外部电路将它输出的电流信号转换为电压信号后进行监测,根据检测数据控制激光器的温度、电压等参数,从而控制激光器输出光信号的波长,达到稳定输出波长的目的。
目前常用的波长锁定器有干涉滤波器和法布里-珀罗标准具(F-P标准具),其中干涉滤波器只能针对某一个特定波长使用,而F-P标准具是通用光学器件,由一对镀有反射膜的平板玻璃和平行的间隔部件组成,封装后基本不受温度和其他电路的影响,利于保持检测信息的准确性。
当一束光照射到F-P标准具上时,产生反射信号和折射信号,光束在F-P标准具的两个平面之间来回反射并逐步透射,透射光的光强It和入射光的光强Ii之间的关系如下式所示:
Figure PCTCN2015077192-appb-000001
其中,n为F-P标准具中平板玻璃的折射率,l为平板玻璃的厚度,λ为入射光的波长,θ为光束的入射角,多个反射光信号叠加后形成的光束由光电二极管转化为电流,多个透射光信号叠加后形成的光束由光电二极管转化为电流,It/Ii随着入射光波长的变化而变化,形成如图2所示的梳状滤波器,其中iE1是透射光形成的电流,iE2是反射光形成的电流,IE是入射光形成的电流,两个梳状滤波器的波峰,波谷互相对称,峰值间周期称为自由光谱区(FSR,free spectral range),其中,FSR=c/(2nlcosθ),其中,c为光速,n为F-P标准具中平板玻璃的折射率,l为平板玻璃的厚度,θ为光束的入射角,梳状滤波 器的形状由锐度公式表示:
Figure PCTCN2015077192-appb-000002
R为F-P标准具中平板玻璃的反射率,F越大,梳状滤波器的形状越陡峭。
从图2中可以看出,入射光束反射后的光信号叠加成的光束由一个光电二极管转化为电流iE2,入射光束透射后的光信号叠加成的光束由另一个光电二极管转化为电流iE1,这两个电流的比值与入射光的波长是相关的,通过这两个电流的比值的变化或者是差值的变化可以判断出入射光的波长的变化。并且,从图2中可以看出,在iE1斜率最大的点mEv附近,同样波长变化体现出来的电流变化最大,可以被认为是线性的。
当激光器出厂时通过预建查找表的方式存下不同波长对应的四段电流值,用于调谐国际电信联盟(ITU,International Telecommunication Union)波长。例如在50GHz间隔的WDM系统中,由于FSR由F-P标准具中平板玻璃的折射率决定,可以设计F-P标准具的周期使其等于50GHz,且F-P标准具的传输函数(即图2所示的曲线)中iE1的曲线与iE2的曲线的交点(即iE1的曲线中斜率最大的点)对准ITU波长表的中心波长,出厂时激光器输出的光的波长是ITU波长点,DSP系统记录下当时通过F-P标准具的电流值,随着时间流逝,当激光器输出的光的波长发生偏移时,光束通过F-P标准具时,可以检测到电流值的变化,这时通过线性调节DS-DBR激光器的管脚电流,可以产生波长的线性变化,从而使检测电流线性变化回到出厂时记录下的电流。
但是,当波长漂移超过F-P标准具的传输函数一个周期时,F-P标准具的传输函数的周期性,会导致无法检测到正确的频率偏移。另外,由于F-P标准具的传输函数上各点的斜率不同,如图2所示,在波峰和波谷之间的A1区域为线性区,在接近峰值顶端的A2区域则是非线性区,当波长漂移落到A2区域,同样的频率偏移对应的电流值变化会小于线性区域,这会造成测量频率偏移的精度变差,而一个确定的系统的电信号总是有最大范围和最小范围的,所以即使后面有放大器可以线性放大频率偏移到A2区域时的电流的变 化,这有可能由于造成频率偏移到A1区域时电流的变化值超出合理范围比如ADC输入电压范围,因此,目前的波长锁定方案的锁定精度受限于频率偏移值的大小,不能做到在全波段范围内的高精度。
综上所述,目前的波长锁定方案在波长漂移超过F-P标准具的传输函数的一个周期时,无法检测到正确的频率偏移;并且目前的波长锁定方案的锁定精度受限于频率偏移值的大小,不能做到在全波段范围内的高精度。
发明内容
本发明实施例提供一种波长锁定器、波长锁定方法和装置,用以解决现有的波长锁定方案在频率漂移超过F-P标准具的传输函数的一个周期时,无法检测到正确的频率偏移,并且锁定精度受限于频率偏移值的大小,不能做到在全波段范围内的高精度。
第一方面,提供一种波长锁定器,包括耦合器、第一法布里-珀罗F-P标准具、第二F-P标准具和检测处理电路;
所述耦合器,用于将接收到的光信号分为两束光信号,所述耦合器接收到的光信号为激光器发射的光信号经过分光后的一束光信号;
所述第一F-P标准具,用于对所述耦合器分成的一束光信号进行反射和折射;所述第一F-P标准具的传输函数的一个周期内的线性区域的最大频率与最小频率之差不大于需求的最小检测精度;
所述第二F-P标准具,用于对所述耦合器分成的另一束光信号进行反射和折射;所述第二F-P标准具的传输函数的周期长度不小于所述激光器的频率偏移的最大值的两倍;所述激光器的预设波长的光信号的频率位于所述第一F-P标准具的传输函数的线性区域、且位于所述第二F-P标准具的传输函数的线性区域;
所述检测处理电路,用于根据所述第一F-P标准具反射的光信号和透射的光信号,以及所述第二F-P标准具反射的光信号和透射的光信号,调整所述激光器的管脚电流,使得所述激光器的频率偏移在误差范围内。
结合第一方面,在第一种可能的实现方式中,所述第二F-P标准具的传输函数的周期长度为所述第一F-P标准具的传输函数的周期长度的正整数倍。
结合第一方面的第一种可能的实现方式,在第二种可能的实现方式中,若所述第二F-P标准具的传输函数在第一频率处为波峰,则所述第一F-P标准具的传输函数在所述第一频率处也为波峰。
结合第一方面,在第三种可能的实现方式中,所述第一F-P标准具的传输函数的一个周期内的线性区域的最大频率与最小频率之差等于需求的最小检测精度。
结合第一方面,在第四种可能的实现方式中,所述检测处理电路具体用于:
根据所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第一预存值之差以及所述激光器输出光信号的设定波长,调整所述激光器的管脚电流,使得所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第一预存值之差不超过第一门限值;
根据所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差以及所述激光器输出光信号的设定波长,调整所述激光器的管脚电流,使得所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差不超过第二门限值;当所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差不超过第二门限值时,所述激光器的频率偏移在误差范围内;
其中,所述第一预存值为激光器发射预设波长的光信号时,所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果;所述第二预存值为激光器发射预设波长的光信号时,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果。
结合第一方面的第四种可能的实现方式,在第五种可能的实现方式中, 所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,是所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值;
所述第一预存值为激光器发射预设波长的光信号时,所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值。
结合第一方面的第四种可能的实现方式,在第六种可能的实现方式中,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,是所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值;
所述第二预存值为激光器发射预设波长的光信号时,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值。
第二方面,提供一种波长锁定方法,包括:
获取第一F-P标准具反射的光信号和透射的光信号,并获取第二F-P标准具反射的光信号和透射的光信号;
根据所述第一F-P标准具反射的光信号和透射的光信号,以及所述第二F-P标准具反射的光信号和透射的光信号,调整所述激光器的管脚电流,使得所述激光器的频率偏移在误差范围内;
其中,所述第一F-P标准具对耦合器分成的一束光信号进行反射和折射;所述耦合器用于将激光器发射的光信号经过分光后的一束光信号分为两束光信号;所述第一F-P标准具的传输函数的一个周期内的线性区域的最大频率与最小频率之差不大于需求的最小检测精度;所述第二F-P标准具对所述耦合器分成的另一束光信号进行反射和折射;所述第二F-P标准具的传输函数的周期长度不小于所述激光器的频率偏移的最大值的两倍;所述激光器的预设波长的光信号的频率位于所述第一F-P标准具的传输函数的线性区域、且位于所述第二F-P标准具的传输函数的线性区域。
结合第二方面,在第一种可能的实现方式中,根据所述第一F-P标准具反射的光信号和透射的光信号,以及所述第二F-P标准具反射的光信号和透 射的光信号,调整所述激光器的管脚电流,使得所述激光器的频率偏移在误差范围内,具体包括:
根据所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第一预存值之差以及所述激光器输出光信号的设定波长,调整所述激光器的管脚电流,使得所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第一预存值之差不超过第一门限值;
根据所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差以及所述激光器输出光信号的设定波长,调整所述激光器的管脚电流,使得所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差不超过第二门限值;当所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差不超过第二门限值时,所述激光器的频率偏移在误差范围内;
其中,所述第一预存值为激光器发射预设波长的光信号时,所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果;所述第二预存值为激光器发射预设波长的光信号时,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果。
结合第二方面的第一种可能的实现方式,在第二种可能的实现方式中,所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,是所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值;
所述第一预存值为激光器发射预设波长的光信号时,所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值。
结合第二方面的第一种可能的实现方式,在第三种可能的实现方式中,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,是所述第一F-P标准具反射的光信号转化的电信号和透射的 光信号转化的电信号的差值;
所述第二预存值为激光器发射预设波长的光信号时,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值。
结合第二方面,在第四种可能的实现方式中,所述第二F-P标准具的传输函数的周期长度为所述第一F-P标准具的传输函数的周期长度的正整数倍。
结合第二方面的第四种可能的实现方式,在第五种可能的实现方式中,若所述第二F-P标准具的传输函数在第一频率处为波峰,则所述第一F-P标准具的传输函数在所述第一频率处也为波峰。
结合第二方面,在第六种可能的实现方式中,所述第一F-P标准具的传输函数的一个周期内的线性区域的最大频率与最小频率之差等于需求的最小检测精度。
第三方面,提供一种波长锁定装置,包括:
获取模块,用于获取第一F-P标准具反射的光信号和透射的光信号,并获取第二F-P标准具反射的光信号和透射的光信号;
调整模块,用于根据所述第一F-P标准具反射的光信号和透射的光信号,以及所述第二F-P标准具反射的光信号和透射的光信号,调整所述激光器的管脚电流,使得所述激光器的频率偏移在误差范围内;
其中,所述第一F-P标准具对耦合器分成的一束光信号进行反射和折射;所述耦合器将激光器发射的光信号经过分光后的一束光信号分为两束光信号;所述第一F-P标准具的传输函数的一个周期内的线性区域的最大频率与最小频率之差不大于需求的最小检测精度;所述第二F-P标准具对所述耦合器分成的另一束光信号进行反射和折射;所述第二F-P标准具的传输函数的周期长度不小于所述激光器的频率偏移的最大值的两倍;所述激光器的预设波长的光信号的频率位于所述第一F-P标准具的传输函数的线性区域、且位于所述第二F-P标准具的传输函数的线性区域。
结合第三方面,在第一种可能的实现方式中,所述调整模块具体用于:
根据所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转 化的电信号的比较结果与第一预存值之差以及所述激光器输出光信号的设定波长,调整所述激光器的管脚电流,使得所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第一预存值之差不超过第一门限值;
根据所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差以及所述激光器输出光信号的设定波长,调整所述激光器的管脚电流,使得所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差不超过第二门限值;当所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差不超过第二门限值时,所述激光器的频率偏移在误差范围内;
其中,所述第一预存值为激光器发射预设波长的光信号时,所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果;所述第二预存值为激光器发射预设波长的光信号时,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果。
结合第三方面的第一种可能的实现方式,在第二种可能的实现方式中,所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,是所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值;
所述第一预存值为激光器发射预设波长的光信号时,所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值。
结合第三方面的第一种可能的实现方式,在第三种可能的实现方式中,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,是所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值;
所述第二预存值为激光器发射预设波长的光信号时,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值。
本发明实施例的有益效果包括:
本发明实施例提供的一种波长锁定器、波长锁定方法和装置,由于第二F-P标准具的传输函数的周期长度不小于所述激光器的频率偏移的最大值的两倍,因此,激光器发射的光信号的波长的偏移不会超过F-P标准具的传输函数的一个周期的一半,即使F-P标准具的传输函数的每个周期的曲线都是对称曲线,那么在激光器的预设波长的光信号的频率位于第二F-P标准具的传输函数的线性区域时,检测处理电路都可以正确检测到激光器发射的光信号的波长发生的偏移量,从而调整激光器的管脚电流,使得激光器发射的光信号的波长接近预设波长。在检测处理电路根据第二F-P标准具反射的光信号和透射的光信号调整调整激光器的管脚电流使得激光器发射的光信号的波长尽可能接近预设波长后,此时激光器发射的光信号的频率位于所述第一F-P标准具的传输函数的线性区域,由于第一F-P标准具的传输函数的一个周期内的线性区域的最大频率与最小频率之差不大于需求的最小检测精度,因此,检测处理电路可以以不大于需求的最小检测精度来测量到激光器发射的光信号的波长发生的偏移量,从而调整激光器的管脚电流,使得所述激光器的频率偏移在误差范围内。因此,在第一F-P标准具与第二F-P标准具结合使用后,检测处理电路可以实现全波段范围内的高精度检测和锁定。
附图说明
图1为现有技术中的DS-DBR可调谐激光器的模型示意图;
图2为现有技术中F-P标准具透射的光信号转换的电流随光信号的频率变化的曲线以及反射的光信号转换的电流随光信号的频率变化的曲线;
图3为本发明实施例提供的波长锁定器的结构示意图之一;
图4为本发明实施例提供的波长锁定器的结构示意图之二;
图5为本发明实施例提供的波长锁定器中的第一F-P标准具的传输函数的曲线以及第二F-P标准具的传输函数的曲线;
图6为本发明实施例提供的波长锁定方法的流程图之一;
图7为本发明实施例提供的波长锁定方法的流程图之二;
图8本发明实施例提供的波长锁定方法应用在实际中时的流程图;
图9为本发明实施例提供的波长锁定装置的结构图。
具体实施方式
本发明实施例提供的一种波长锁定器、波长锁定方法和装置,由第二F-P标准具与检测处理电路实现频率偏移量的正确检测,并实现激光器发射的光信号的波长的粗调,由第一F-P标准具与检测处理电路实现频率偏移量的高精度检测,并实现激光器发射的光信号的波长的高精度锁定。
下面结合说明书附图,对本发明实施例提供的一种波长锁定器和波长锁定方法和装置的具体实施方式进行说明。
本发明实施例提供的波长锁定器,如图3所示,包括耦合器31、第一法布里-珀罗F-P标准具32、第二F-P标准具33和检测处理电路34;
耦合器31,用于将接收到的光信号分为两束光信号,耦合器31接收到的光信号为激光器35发射的光信号经过分光后的一束光信号;
第一F-P标准具32,用于对耦合器31分成的一束光信号进行反射和折射;第一F-P标准具32的传输函数的一个周期内的线性区域的最大频率与最小频率之差不大于需求的最小检测精度;
第二F-P标准具33,用于对耦合器31分成的另一束光信号进行反射和折射;第二F-P标准具33的传输函数的周期长度不小于激光器35的频率偏移的最大值的两倍;激光器35的预设波长的光信号的频率位于第一F-P标准具32的传输函数的线性区域、且位于第二F-P标准具33的传输函数的线性区域;
检测处理电路34,用于根据第一F-P标准具32反射的光信号和透射的光信号,以及第二F-P标准具33反射的光信号和透射的光信号,调整激光器35的管脚电流,使得激光器35的频率偏移在误差范围内。
可选地,在实际中应用时,本发明实施例提供的波长锁定器可以采用图4所述的结构,其中,检测处理电路包括了四个光电二极管41、四个第一跨阻 放大器42、两个减法器43、比例积分微分(P.I.D)控制单元、数字信号处理(DSP)单元45和四个第二跨阻放大器46。
激光器35输出波长为λ0,功率为P0的光信号,进入到PID控制单元的电压信号为:
VE11(ν)=α1α2P0RE11A11TE1(ν);
VE12(ν)=α1α2P0RE12A12(1-TE1(ν));
VE21(ν)=α1α2P0RE21A21TE2(ν);
VE22(ν)=α1α2P0RE22A22(1-TE2(ν));
其中α1是将激光器发35射的光信号进行分光的耦合器的分光比,α2是耦合器31的分光比,RE11RE12RE21RE22是分别是四个光电二极管的响应度,A11A12A21A22分别是四个跨阻放大器的放大倍数,TE1是第一F-P标准具的传输函数,TE2是第二F-P标准具的传输函数:
TE1(ν)=[1+FE1sin2(πν/Δνfine)];
TE2(ν)=[1+FE2sin2(πν/Δνcorase)];
FE1为第一F-P标准具的锐度,FE2为第二F-P标准具的锐度,Δνfine为第一F-P标准具的FSR,Δνcorase为第二F-P标准具的FSR。
从进入到PID控制单元的信号的表达式中可以看出,同一个F-P标准具反射光信号对应的电流周期和透射光信号对应的电流周期是一致的,其中,第一F-P标准具的传输函数的周期为Δνfine,第二F-P标准具的传输函数的周期为Δνcorase
由于F-P标准具的传输函数的周期和相位取决于入射光的波长、角度、平板间隔、平板材料反射率,在第一F-P标准具和第二F-P标准具的入射光的波长相同,入射光的角度相同的情况下,使用不同的平板间隔和不同反射率的材料就可以设计出传输函数的周期和相位完全满足要求的两个F-P标准具。
可选地,所述第二F-P标准具的传输函数的周期长度为所述第一F-P标准具的传输函数的周期长度的正整数倍。这样当激光器为可调谐激光器时,激 光器在出厂时设置的每一个可发射的光信号的波长都能够既位于第一F-P标准具的传输函数的线性区域,又位于第二标准具的传输函数的线性区域。
可选地,若所述第二F-P标准具的传输函数在第一频率处为波峰,则所述第一F-P标准具的传输函数在所述第一频率处也为波峰。也就是说,第二F-P标准具的传输函数的波峰的位置与第一F-P标准具的传输函数的一部分波峰的位置是重叠的,这样可以确保激光器的预设波长的光信号的频率位于所述第一F-P标准具的传输函数的线性区域、且位于所述第二F-P标准具的传输函数的线性区域。
可选地,所述第一F-P标准具的传输函数的一个周期内的线性区域的最大频率与最小频率之差等于需求的最小检测精度。
可选地,本发明实施例提供的波长锁定器中的检测处理电路具体用于:根据所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第一预存值之差以及所述激光器输出光信号的设定波长,调整所述激光器的管脚电流,使得所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第一预存值之差不超过第一门限值;
根据所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差以及所述激光器输出光信号的设定波长,调整所述激光器的管脚电流,使得所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差不超过第二门限值;
其中,所述第一预存值为激光器发射预设波长的光信号时,所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果;所述第二预存值为激光器发射预设波长的光信号时,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果。
当第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第一预存值之差不超过第一门限值,且第一F-P标准具反 射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差不超过第二门限值时,激光器发射的光信号的波长在误差范围内。
其中,第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,可以是第二F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号之差,也可以是第二F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号之比。当第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,是第二F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号之差时,第一预存值是激光器在输出设定波长的光信号时第二F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号的差值。当第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,是第二F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号之比时,第一预存值是激光器在输出设定波长的光信号时第二F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号的比值。
所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,可以是第一F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号之差,也可以是第一F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号之比。当第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,是第一F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号之差时,第二预存值是激光器在输出设定波长的光信号时第一F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号的差值。当第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,是第一F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号之比时,第二预存值是激光器在输出设定波长的光信号时第一F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号的比值。
其中,预设波长是在出厂时设置的激光器发射的光信号的波长,激光器 发射的光信号的波长与该光信号的频率的乘积等于光速,因此,当激光器发射的光信号的频率发生偏移,也就意味着激光器发射的光信号的波长偏离了预设波长。由于第一F-P标准具的传输函数和第二F-P标准具的传输函数不同,因此同样的频率偏移经过不同F-P标准具反射、透射后的光信号转化的电流是不同的。
假设激光器的频率偏移的最大值为0.1THz,要求的最小检测精度为0.02THz,那么可以采用如图5所示的曲线的传输函数的两个F-P标准具来检测并锁定激光器发射的光信号的波长。假设预设波长对应的频率为192.1125THz(即q1点),在波长锁定器出厂校验时,通过仪器校准将激光器发射该波长的光信号时(假设激光器在生命周期的初始阶段并没有频率偏移)通过第一F-P标准具和第二F-P标准具后产生的电压保存为Ve1和Ve2,并记录下当前从DSP发送到激光器控制激光器的管脚的电压值VR/VP/VG/VG。
若激光器发射的光信号的波长发生漂移,激光器发射的光信号的频率由192.1125THz(即q1点)变到192.22THz(即p1点)时,检测处理电路由第二F-P标准具透射和反射的光信号得到波长发生漂移后的电压VE2,并根据波长发生漂移后的电压VE2和预设波长时第二F-P标准具透射和反射的光信号的电压Ve2(即第一预存值)就可以在第二F-P标准具(图5中的实线)上唯一的确定出一个点p1,对比VE2和Ve2的差值就可以对可调谐激光器管脚(front/rear)施加电流的大小进行粗调,使得VE2接近Ve2,当调整至VE2和Ve2的差值不超过一定门限时,VE2在第二F-P标准具的传输函数上对应的点为q2,q2点的波长在第一F-P标准具的传输函数(图5中的虚线)上的电压为VE1,将VE1和预设波长时第一F-P标准具透射和反射的光信号的Ve1(即第二预存值)对比后,可以对可调谐激光器管脚施加电流的大小进行细调,使得VE1接近Ve1,当调整到VE1和Ve1差值不超过一定门限时,可以认为激光器发射的光信号的波长已经在误差范围内了,即完成了波长锁定。
本发明实施例提供的一种波长锁定方法,如图6所示,包括:
S601、获取第一F-P标准具反射的光信号和透射的光信号,并获取第二 F-P标准具反射的光信号和透射的光信号;
S602、根据所述第一F-P标准具反射的光信号和透射的光信号,以及所述第二F-P标准具反射的光信号和透射的光信号,调整激光器的管脚电流,使得所述激光器的频率偏移在误差范围内;
其中,所述第一F-P标准具对耦合器分成的一束光信号进行反射和折射;所述耦合器将激光器发射的光信号经过分光后的一束光信号分为两束光信号;所述第一F-P标准具的传输函数的一个周期内的线性区域的最大频率与最小频率之差不大于需求的最小检测精度;所述第二F-P标准具对所述耦合器分成的另一束光信号进行反射和折射;所述第二F-P标准具的传输函数的周期长度不小于所述激光器的频率偏移的最大值的两倍;所述激光器的预设波长的光信号的频率位于所述第一F-P标准具的传输函数的线性区域、且位于所述第二F-P标准具的传输函数的线性区域。
可选地,本发明实施例提供的一种波长锁定方法,如图7所示,S602具体包括:
S701、根据所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第一预存值之差以及所述激光器输出光信号的设定波长,调整所述激光器的管脚电流,使得所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第一预存值之差不超过第一门限值;
S702、根据所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差以及所述激光器输出光信号的设定波长,调整所述激光器的管脚电流,使得所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差不超过第二门限值;当所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差不超过第二门限值时,所述激光器的频率偏移在误差范围内;
其中,所述第一预存值为激光器发射预设波长的光信号时,所述第二F-P 标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果;所述第二预存值为激光器发射预设波长的光信号时,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果。
在实际中,粗调(即S701)可能要经过不止一次获取第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果、与第一预存值对比、以及调整激光器的管脚电流才能使得所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第一预存值之差不超过第一门限值;,并且细调(S702)也可能要经过不止一次获取第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果、与第二预存值对比、以及调整激光器的管脚电流才能完成波长锁定。在粗调和细调的过程中,在调整激光器的管脚电流后,激光器发射的光信号的波长可能位于F-P标准具的线性区域,也可能位于F-P标准具的非线性区域,在非线性区域时,需要对比激光器管脚电压调整前后F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,来确定激光器发射的光信号的波长移动的方向,从而完成波长锁定。
其中,第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,可以是第二F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号之差,也可以是第二F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号之比。当第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,是第二F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号之差时,第一预存值是激光器在输出设定波长的光信号时第二F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号的差值。当第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,是第二F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号之比时,第一预存值是激光器在输出设定波长的光信号时第二F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号的比值。
所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,可以是第一F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号之差,也可以是第一F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号之比。当第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,是第一F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号之差时,第二预存值是激光器在输出设定波长的光信号时第一F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号的差值。当第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,是第一F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号之比时,第二预存值是激光器在输出设定波长的光信号时第一F-P标准具反射的光信号转化的电信号与透射的光信号转化的电信号的比值。
可选地,所述第二F-P标准具的传输函数的周期长度为所述第一F-P标准具的传输函数的周期长度的正整数倍。
可选地,若所述第二F-P标准具的传输函数在第一频率处为波峰,则所述第一F-P标准具的传输函数在所述第一频率处也为波峰。
可选地,所述第一F-P标准具的传输函数的一个周期内的线性区域的最大频率与最小频率之差等于需求的最小检测精度。
图8为本发明实施例提供的波长锁定方法应用在实际中时的流程图,包括:
S801、获取第一F-P标准具反射的光信号和透射的光信号,并获取第二F-P标准具反射的光信号和透射的光信号;
S802、根据第一F-P标准具反射的光信号和透射的光信号确定第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,并根据第二F-P标准具反射的光信号和透射的光信号确定第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果;
S803、根据第二F-P标准具反射的光信号转化的电信号和透射的光信号 转化的电信号的比较结果与第一预存值之差,以及预设波长,确定激光器管脚电流调整的方向(即增大还是减小)和大小,并调整激光器管脚电流;
S804、判断第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第一预存值之差是否小于第一门限值,若是,执行S805;否则执行S803;
S805、根据第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差,以及预设波长,确定激光器管脚电流调整的方向(即增大还是减小)和大小,并调整激光器管脚电流;
S806、判断第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差是否小于第二门限值,若是,执行S807,否则,执行S805;
S807、波长锁定完成,即激光器发射的光信号的波长在误差范围内。
基于同一发明构思,本发明实施例还提供了一种波长锁定装置,由于该装置所解决问题的原理与前述波长锁定方法相似,因此该装置的实施可以参见前述方法的实施,重复之处不再赘述。
本发明实施例提供的波长锁定装置,如图9所示,包括:
获取模块91,用于获取第一F-P标准具反射的光信号和透射的光信号,并获取第二F-P标准具反射的光信号和透射的光信号;
调整模块92,用于根据所述第一F-P标准具反射的光信号和透射的光信号,以及所述第二F-P标准具反射的光信号和透射的光信号,调整所述激光器的管脚电流,使得所述激光器的频率偏移在误差范围内;
其中,所述第一F-P标准具对耦合器分成的一束光信号进行反射和折射;所述耦合器将激光器发射的光信号经过分光后的一束光信号分为两束光信号;所述第一F-P标准具的传输函数的一个周期内的线性区域的最大频率与最小频率之差不大于需求的最小检测精度;所述第二F-P标准具对所述耦合器分成的另一束光信号进行反射和折射;所述第二F-P标准具的传输函数的周期长度不小于所述激光器的频率偏移的最大值的两倍;所述激光器的预设 波长的光信号的频率位于所述第一F-P标准具的传输函数的线性区域、且位于所述第二F-P标准具的传输函数的线性区域。
可选地,调整模块92具体用于:
根据所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第一预存值之差以及所述激光器输出光信号的设定波长,调整所述激光器的管脚电流,使得所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第一预存值之差不超过第一门限值;
根据所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差以及所述激光器输出光信号的设定波长,调整所述激光器的管脚电流,使得所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差不超过第二门限值;当所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差不超过第二门限值时,所述激光器的频率偏移在误差范围内;
其中,所述第一预存值为激光器发射预设波长的光信号时,所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果;所述第二预存值为激光器发射预设波长的光信号时,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果。
本领域内的技术人员应明白,本发明的实施例可提供为方法、系统、或计算机程序产品。因此,本发明可采用完全硬件实施例、完全软件实施例、或结合软件和硬件方面的实施例的形式。而且,本发明可采用在一个或多个其中包含有计算机可用程序代码的计算机可用存储介质(包括但不限于磁盘存储器、CD-ROM、光学存储器等)上实施的计算机程序产品的形式。
本发明是参照根据本发明实施例的方法、设备(系统)、和计算机程序产品的流程图和/或方框图来描述的。应理解可由计算机程序指令实现流程图和/或方框图中的每一流程和/或方框、以及流程图和/或方框图中的流程 和/或方框的结合。可提供这些计算机程序指令到通用计算机、专用计算机、嵌入式处理机或其他可编程数据处理设备的处理器以产生一个机器,使得通过计算机或其他可编程数据处理设备的处理器执行的指令产生用于实现在流程图一个流程或多个流程和/或方框图一个方框或多个方框中指定的功能的装置。
这些计算机程序指令也可存储在能引导计算机或其他可编程数据处理设备以特定方式工作的计算机可读存储器中,使得存储在该计算机可读存储器中的指令产生包括指令装置的制造品,该指令装置实现在流程图一个流程或多个流程和/或方框图一个方框或多个方框中指定的功能。
这些计算机程序指令也可装载到计算机或其他可编程数据处理设备上,使得在计算机或其他可编程设备上执行一系列操作步骤以产生计算机实现的处理,从而在计算机或其他可编程设备上执行的指令提供用于实现在流程图一个流程或多个流程和/或方框图一个方框或多个方框中指定的功能的步骤。
尽管已描述了本发明的优选实施例,但本领域内的技术人员一旦得知了基本创造性概念,则可对这些实施例作出另外的变更和修改。所以,所附权利要求意欲解释为包括优选实施例以及落入本发明范围的所有变更和修改。
显然,本领域的技术人员可以对本发明实施例进行各种改动和变型而不脱离本发明实施例的精神和范围。这样,倘若本发明实施例的这些修改和变型属于本发明权利要求及其等同技术的范围之内,则本发明也意图包含这些改动和变型在内。

Claims (18)

  1. 一种波长锁定器,其特征在于,包括耦合器、第一法布里-珀罗F-P标准具、第二F-P标准具和检测处理电路;
    所述耦合器用于将接收到的光信号分为两束光信号,所述耦合器接收到的光信号为激光器发射的光信号经过分光后的一束光信号;
    所述第一F-P标准具,用于对所述耦合器分成的一束光信号进行反射和折射;所述第一F-P标准具的传输函数的一个周期内的线性区域的最大频率与最小频率之差不大于需求的最小检测精度;
    所述第二F-P标准具,用于对所述耦合器分成的另一束光信号进行反射和折射;所述第二F-P标准具的传输函数的周期长度不小于所述激光器的频率偏移的最大值的两倍;所述激光器的预设波长的光信号的频率位于所述第一F-P标准具的传输函数的线性区域、且位于所述第二F-P标准具的传输函数的线性区域;
    所述检测处理电路,用于根据所述第一F-P标准具反射的光信号和透射的光信号,以及所述第二F-P标准具反射的光信号和透射的光信号,调整所述激光器的管脚电流,使得所述激光器的频率偏移在误差范围内。
  2. 如权利要求1所述的波长锁定器,其特征在于,所述第二F-P标准具的传输函数的周期长度为所述第一F-P标准具的传输函数的周期长度的正整数倍。
  3. 如权利要求2所述的波长锁定器,其特征在于,若所述第二F-P标准具的传输函数在第一频率处为波峰,则所述第一F-P标准具的传输函数在所述第一频率处也为波峰。
  4. 如权利要求1所述的波长锁定器,其特征在于,所述第一F-P标准具的传输函数的一个周期内的线性区域的最大频率与最小频率之差等于需求的最小检测精度。
  5. 如权利要求1所述的波长锁定器,其特征在于,所述检测处理电路具 体用于:
    根据所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第一预存值之差以及所述激光器输出光信号的设定波长,调整所述激光器的管脚电流,使得所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第一预存值之差不超过第一门限值;
    根据所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差以及所述激光器输出光信号的设定波长,调整所述激光器的管脚电流,使得所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差不超过第二门限值;当所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差不超过第二门限值时,所述激光器的频率偏移在误差范围内;
    其中,所述第一预存值为激光器发射预设波长的光信号时,所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果;所述第二预存值为激光器发射预设波长的光信号时,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果。
  6. 如权利要求5所述的波长锁定器,其特征在于,所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,是所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值;
    所述第一预存值为激光器发射预设波长的光信号时,所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值。
  7. 如权利要求5所述的波长锁定器,其特征在于,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,是所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值;
    所述第二预存值为激光器发射预设波长的光信号时,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值。
  8. 一种波长锁定方法,其特征在于,包括:
    获取第一F-P标准具反射的光信号和透射的光信号,并获取第二F-P标准具反射的光信号和透射的光信号;
    根据所述第一F-P标准具反射的光信号和透射的光信号,以及所述第二F-P标准具反射的光信号和透射的光信号,调整激光器的管脚电流,使得所述激光器的频率偏移在误差范围内;
    其中,所述第一F-P标准具对耦合器分成的一束光信号进行反射和折射;所述耦合器将激光器发射的光信号经过分光后的一束光信号分为两束光信号;所述第一F-P标准具的传输函数的一个周期内的线性区域的最大频率与最小频率之差不大于需求的最小检测精度;所述第二F-P标准具对所述耦合器分成的另一束光信号进行反射和折射;所述第二F-P标准具的传输函数的周期长度不小于所述激光器的频率偏移的最大值的两倍;所述激光器的预设波长的光信号的频率位于所述第一F-P标准具的传输函数的线性区域、且位于所述第二F-P标准具的传输函数的线性区域。
  9. 如权利要求8所述的方法,奇特征在于,根据所述第一F-P标准具反射的光信号和透射的光信号,以及所述第二F-P标准具反射的光信号和透射的光信号,调整所述激光器的管脚电流,使得所述激光器的频率偏移在误差范围内,具体包括:
    根据所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第一预存值之差以及所述激光器输出光信号的设定波长,调整所述激光器的管脚电流,使得所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第一预存值之差不超过第一门限值;
    根据所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差以及所述激光器输出光信号的设定 波长,调整所述激光器的管脚电流,使得所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差不超过第二门限值;当所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差不超过第二门限值时,所述激光器的频率偏移在误差范围内;
    其中,所述第一预存值为激光器发射预设波长的光信号时,所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果;所述第二预存值为激光器发射预设波长的光信号时,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果。
  10. 如权利要求9所述的方法,其特征在于,所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,是所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值;
    所述第一预存值为激光器发射预设波长的光信号时,所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值。
  11. 如权利要求9所述的方法,其特征在于,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,是所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值;
    所述第二预存值为激光器发射预设波长的光信号时,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值。
  12. 如权利要求8所述的方法,其特征在于,所述第二F-P标准具的传输函数的周期长度为所述第一F-P标准具的传输函数的周期长度的正整数倍。
  13. 如权利要求12所述的方法,其特征在于,若所述第二F-P标准具的传输函数在第一频率处为波峰,则所述第一F-P标准具的传输函数在所述第一频率处也为波峰。
  14. 如权利要求8所述的方法,其特征在于,所述第一F-P标准具的传 输函数的一个周期内的线性区域的最大频率与最小频率之差等于需求的最小检测精度。
  15. 一种波长锁定装置,其特征在于,包括:
    获取模块,用于获取第一F-P标准具反射的光信号和透射的光信号,并获取第二F-P标准具反射的光信号和透射的光信号;
    调整模块,用于根据所述第一F-P标准具反射的光信号和透射的光信号,以及所述第二F-P标准具反射的光信号和透射的光信号,调整所述激光器的管脚电流,使得所述激光器的频率偏移在误差范围内;
    其中,所述第一F-P标准具对耦合器分成的一束光信号进行反射和折射;所述耦合器用于将激光器发射的光信号经过分光后的一束光信号分为两束光信号;所述第一F-P标准具的传输函数的一个周期内的线性区域的最大频率与最小频率之差不大于需求的最小检测精度;所述第二F-P标准具对所述耦合器分成的另一束光信号进行反射和折射;所述第二F-P标准具的传输函数的周期长度不小于所述激光器的频率偏移的最大值的两倍;所述激光器的预设波长的光信号的频率位于所述第一F-P标准具的传输函数的线性区域、且位于所述第二F-P标准具的传输函数的线性区域。
  16. 如权利要求15所述的装置,其特征在于,所述调整模块具体用于:
    根据所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第一预存值之差以及所述激光器输出光信号的设定波长,调整所述激光器的管脚电流,使得所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第一预存值之差不超过第一门限值;
    根据所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差以及所述激光器输出光信号的设定波长,调整所述激光器的管脚电流,使得所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果与第二预存值之差不超过第二门限值;当所述第一F-P标准具反射的光信号转化的电信号和透射 的光信号转化的电信号的比较结果与第二预存值之差不超过第二门限值时,所述激光器的频率偏移在误差范围内;
    其中,所述第一预存值为激光器发射预设波长的光信号时,所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果;所述第二预存值为激光器发射预设波长的光信号时,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果。
  17. 如权利要求16所述的装置,其特征在于,所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,是所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值;
    所述第一预存值为激光器发射预设波长的光信号时,所述第二F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值。
  18. 如权利要求16所述的装置,其特征在于,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的比较结果,是所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值;
    所述第二预存值为激光器发射预设波长的光信号时,所述第一F-P标准具反射的光信号转化的电信号和透射的光信号转化的电信号的差值。
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CN113097860A (zh) * 2021-03-10 2021-07-09 浙江大学 半导体激光器驱动电流电路及输出频率实时反馈方法

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CN111385020B (zh) * 2018-12-29 2022-04-29 海思光电子有限公司 一种波长测量装置

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