CN100553054C - A kind of separate type ultra-large power semiconductor array cavity distortion compensation rate half amount is obtained technology - Google Patents

Abstract

The invention provides in a kind of ultra-high power semiconductor array, overcoming exocoel deformation influences phase-locked quality, compensates the required compensation rate of deformation and obtains technology for avoiding reducing phase-locked quality.The subsystem of a drive test amount exocoel deformation relevant with CCD1 utilizes speculum R2.1, speculum 3, zoom optics 1, lens 1, half the He-Ne laser beam image that focuses on the outer cavity reflection of warp is on CCD1, calculate facula mass center by processor 1, and calculate calibrated variable quantity, thereby obtain the deformation data of a direction of external cavity mirror, and when it reaches thresholding, obtain method and know compensation rate by partly measuring compensation rate, and then cooperate corresponding D/A, corresponding high drive module, drive installation is expanded at the corresponding piezoelectricity compensator PZT of external cavity mirror terminal position, compensation, thereby timely compensation β is in the drift of a direction, serve the external cavity mirror deformation at random that timely compensation is caused by residual heat effect etc., make and adopt the phase-locked ultra large power two-dimensional semiconductor array stable ground of external cavity mirror of coupling angle to shake, ensure the high-quality of array stable output in the homophase mould.

Description

A kind of separate type ultra-large power semiconductor array cavity distortion compensation rate half amount is obtained technology

Technical field

The exocoel deformation compensation rate that the invention belongs to the Stability Control of serving the operation of ultra-high power semiconductor array selection homophase mould is obtained technology, it is phase-locked to relate to ultra-large power semiconductor array cavity, after relating to external cavity mirror by the adaptive angle of deflection and making array select the concussion of homophase mould, residual heat effect etc. is caused the measurement of exocoel deformation, relate to compensation array external cavity deformation compensation rate and obtain, relate to and avoid exocoel deformation to cause the starting of oscillation of non-homophase mould.

Background technology

Semi-conductor array quantum efficiency height, the output wavelength scope contains 570nm to 1600nm, working life can reach millions of hours, the lamination array can provide the output of ultra high power laser, such as industry, a lot of fields such as medical science have boundless and good prospects for application, but because that each luminescence unit of semi-conductor array of free-running operation sends is only incoherent, its output quality is relatively poor, particularly the angle of divergence of slow axis multimode output is big, spectral width, disturbing, chromatic dispersion, aspect characteristic extreme differences such as directivity, both can't focus on small size by optical system, can't realize long-distance transmissions again, seriously hinder it in machining, surface treatment, the high power density pumping, obtain in the fields such as space high speed optical communication effectively to use.Thereby, take the phase-locked measure in space to make each unit run on identical wavelength and make and have fixing phase difference between them, it is most important just to become.

Realize that the relevant operation method in each unit comprises inner couplings and coupled outside.Inner couplings distributes, constructs suitable measures such as active layer, substrate and cover layer by control refractive index, gain region makes the position obtain locking mutually, but the corresponding luminescence unit width of this kind mechanism has limited the power that semi-conductor array can be exported greatly, in addition, its corresponding systematic jitters can increasing with the increase of drive current and increase along with luminescence unit.Coupled outside is by realizing phase-locked output in outside phase conjugate lens feedback injection locking technique, principal and subordinate's laser injection locking technique, the external cavity mirror technology of adopting of semi-conductor array.

Reach hundreds of microns high power semiconductor laser array for adjacent luminescence unit distance, suitable especially employing is phase-locked based on the exocoel coupling of mode coupling theory and Talbot chamber theory, the corresponding power coupling mainly occurs between the next-door neighbour unit, the coupling of non-adjacent unit can be ignored, and corresponding system is simple in structure and effect is good.

Utilize the work medium wavelength to be λ, the slow axis array cycle is d, and the chamber is long to be L _C=d ²/ 2 λ, the external cavity mirror normal direction can successfully lock the high power semiconductor laser array phase place perpendicular to the 1/4Talbot external cavity mirror technology of slow axis, but corresponding far-field distribution is the bivalve structure, indicates that corresponding concussion pattern is the out-phase mould; According to mark Talbot chamber field distribution rule, shake in the homophase mould for making system, to obtain far-field distribution is the single-lobe structure, splendid output near diffraction limit, must be with this 1/4Talbot external cavity mirror at slow-axis direction deflection certain angle suitably, this is the mode that two-dimensional semiconductor lamination array adopts the concussion of exocoel choice of technology homophase mould, successfully obtain Project Realization, yet, be applied to the ultra large power two-dimensional semiconductor array when phase-locked in this technology, after the external cavity mirror of the adaptive angle that tilts makes array select the concussion of homophase mould, though cooling subsystem can ensure the array continuous firing, but the residual heat effect can make that still exocoel deformation constantly aggravates, add platform vibrations etc., cause the concussion of out-phase mould.Therefore, must take steady mould measure to the ultra large power two-dimensional semiconductor array, so that array can stably shake in the homophase mould, the outputting high quality laser beam, for this reason, the present invention has provided a kind of separate type ultra-large power semiconductor array cavity distortion compensation rate and has obtained technology, be one step of key of compensation β drift, only after obtaining compensation rate, the exocoel deformation compensating mechanism just can be activated, after itself and supporting exocoel deformation compensation technique coupling, array can stably be selected the operation of homophase mode oscillation.

Summary of the invention

The technical problem that the present invention is directed to is described: when the external cavity mirror that adopts the phase-locked semi-conductor array of 1/4Talbot external cavity mirror technology during perpendicular to luminescence unit, the homophase mould light that external cavity mirror is sent luminescence unit reflects and images between luminescence unit, thereby, cavity loss is very big, but the out-phase mould light that luminescence unit is sent reflection also images in the luminescence unit, thereby the phase-locked semi-conductor array of 1/4Talbot external cavity mirror technology will select out-phase mould concussion, and array and corresponding light field distribution are as shown in Figure 1.Behind external cavity mirror deflection β=λ/2d, as shown in Figure 2, the light that luminescence unit sends after external cavity mirror reflection with deflection λ/d, correspondingly, as shown in Figure 3, homophase mould light that is reflected and out-phase mould light will exchange the two image space at luminescence unit, thereby, adopt the phase-locked semi-conductor array of 1/4Talbot external cavity mirror technology of inclination β=λ/2d will select the concussion of homophase mould, but, for the phase-locked ultra large power two-dimensional semiconductor array of this technology of employing, though the cooling subsystem of array can ensure the array continuous firing, along with the increase of array power output, because residual heat effect etc. acts on external cavity mirror, to cause the β drift, be any one luminescence unit of S for Guang Fa district slow axis width, when the β drift surpasses S λ/2d ²The time, the homophase mould reverberation that surpasses half will image between the luminescence unit, cause the out-phase mould to be dominant; When the β drift surpasses ((d-S) λ)/2d ²The time, the out-phase mould reverberation that surpasses half will image in the lightening hole, also will cause the out-phase mould to be dominant, shake in the homophase mould for ensureing array invariablely, must compensate the β drift that external cavity mirror deformation causes in time, and exocoel deformation compensation rate to obtain be the system input source spring that successfully compensates, for compensating operation, be the decision key of success first step.

The technical problem solution that the present invention is directed to: along with the increase of array output homophase mould laser power, make β that the two-way drift of near symmetrical take place for the residual heat effect, adopt two groups of external cavity mirror distortion sensings and compensation equipment, Fig. 4 is the corresponding system structural design, constitutes element, reaches the operation schematic diagram, and the transmission length that the laser that its each luminescence unit sends is sent to external cavity mirror is L _C=d ²/ 2 λ, promptly the 1/4Talbot chamber is long.Spectroscope 1 is divided into two the He-Ne laser that active sensing light source sends, its reverberation reflects and projects on the external cavity mirror reflecting surface through speculum 1 reflection, coupling beam expanding lens expansion bundle, spectroscope 2, immediately, penetrated spectroscope 2 by external cavity mirror laser light reflected bundle, after speculum R2.1 and R2.2, speculum 3 reflections, the laser beam that zoom optics 1 is regulated from R2.1 makes lens 1 focusing self incident beam on CCD1, calculates this facula mass center by processor 1; Meanwhile, the laser beam that zoom optics 2 is regulated from R2.2 makes lens 2 that second half incident beam is imaged on the CCD2, calculates this facula mass center by processor 2.When deformation did not take place external cavity mirror, a facula mass center was (x _C0, y _C0), after demarcation, after the external cavity mirror generation deformation, certain deviation will take place and become (x in corresponding facula mass center _C1, y _C1), processor 1 calculates the variable quantity that CCD1 goes up the imaging facula barycenter in real time, and when it reaches thresholding, partly measuring compensation rate by operation obtains method (referring to embodiment) and knows compensation rate, and then cooperate corresponding D/A, corresponding high drive module, drive installation is expanded at the corresponding piezoelectricity compensator PZT of external cavity mirror terminal position shown in Figure 4, finish the compensating operation of the external cavity mirror deformation of corresponding R2.1, the deformation of a direction of external cavity mirror is compensated, thereby timely compensation β is in the drift of a direction; Simultaneously, processor 2 calculates the variable quantity that CCD2 goes up the imaging facula barycenter in real time, and when it reaches thresholding, obtain method by operation full dose compensation rate and know compensation rate, and then cooperating corresponding D/A, corresponding high drive module, the piezoelectricity compensator PZT of drive installation terminal position on R2.2 shown in Figure 4 expands, and finishes the compensating operation of the external cavity mirror deformation of corresponding R2.2, the deformation of external cavity mirror another one direction is compensated, thereby timely compensation β is in the drift of another one direction.So, by the state of exocoel distortion sensing equipment real-time perception external cavity mirror, the compensation equipment timely compensation makes the exocoel lock phase array overcome the influence that the β drift brings, and stably shakes in the homophase mould and moves.

Description of drawings

Fig. 1 is phase-locked semi-conductor array of 1/4Talbot external cavity mirror technology and corresponding light field distribution schematic diagram;

Fig. 2 makes array select homophase mould concussion desired location condition schematic diagram, β=λ/2d for the external cavity mirror of the adaptive angle that tilts;

Fig. 3 is the array feedback light field distribution schematic diagram of corresponding diagram 2;

Fig. 4 is the system schematic of the given technology of operation the present invention;

Fig. 5 is for before adopting given technology of the present invention and supporting exocoel deformation compensation technique thereof, the typical output field of the phase-locked operation of ultra-high power semiconductor array distributes, be out of shape owing to external cavity mirror is influenced by residual heat effect etc., cause non-homophase mode oscillation, the far field has become three valve structures.

Fig. 6 is for after adopting given technology of the present invention and supporting exocoel deformation compensation technique thereof, and the typical output field of the phase-locked operation of ultra-high power semiconductor array distributes, and is the single-lobe structure, as seen, the β drift is corrected, and exocoel distortion sensing Compensation subsystem runs on the homophase mould with can ensureing array stable

The present invention can the phase-locked operation of servo well array stable.

Specify content of the present invention below by example:

Embodiment

Adopt the He-Ne laser as active sensing light source, spectroscope 1 is transmitted light part and reverberation part with its laser beam splitting that sends, its transmitted light partly will directly project by special permanent plant and be fixed on the 4 quadrant detector on the external cavity mirror, to measure the displacement of its place end external cavity mirror, the thermal coefficient of expansion and the external cavity mirror of permanent plant are close, 4 quadrant detector is parallel to the external cavity mirror reflecting surface, on the one hand, can be under processor 1 control, cooperate applied voltage, measure the displacement of its place end external cavity mirror, be compensated the required compensation response of calculation of equipments compensation rate, this has simplified relevant series operation greatly; On the other hand, when corresponding compensation equipment was carried out compensation, based on the displacement that the displacement measurement system of 4 quadrant detector is measured its place end external cavity mirror in good time, the compensation rate that the monitoring compensation equipment is carried out provided foundation for optimizing the performance weighting.

The reverberation part of spectroscope 1 will be by speculum 1 reflection, after the coupling beam expanding lens expands bundle, again by spectroscope 2 reflections, this section H e-Ne laser beam is projected on the 1/4Talbot external cavity mirror reflecting surface, thereafter, to be penetrated spectroscope 2 by the external cavity mirror beam reflected, through speculum R2.1 and R2.2 reflection, again after speculum 3 reflections, the light beam of corresponding R2.1 will be regulated through zoom optics 1, with matched lenses 1, image in CCD1, the He-Ne laser beam of corresponding R2.2 is through zoom optics 2, lens 2 image in CCD2, no matter be the imaging facula of corresponding CCD1 or the imaging facula of corresponding CCD2, facula mass center (x _C, y _C) can pass through

$x_C=\frac{\underset{i=1}{\overset{M}{\mathrm{\Σ}}}\underset{j=1}{\overset{N}{\mathrm{\Σ}}}{x}_{\mathrm{ij}}{I}_{\mathrm{ij}}}{\underset{i=1}{\overset{M}{\mathrm{\Σ}}}\underset{j=1}{\overset{N}{\mathrm{\Σ}}}{I}_{\mathrm{ij}}},y_C=\frac{\underset{i=1}{\overset{M}{\mathrm{\Σ}}}\underset{j=1}{\overset{N}{\mathrm{\Σ}}}{y}_{\mathrm{ij}}{I}_{\mathrm{ij}}}{\underset{i=1}{\overset{M}{\mathrm{\Σ}}}\underset{j=1}{\overset{N}{\mathrm{\Σ}}}{I}_{\mathrm{ij}}}$

Calculate, M is the line number in the CCD pel array formula in the formula, and N is the columns in the CCD pel array formula, x _IjBe pixel (i, x coordinate j), y _IjBe pixel (i, Y coordinate j), I _IjRespective pixel (i, output intensity value j).If when deformation does not take place external cavity mirror, a facula mass center is (x _C0, y _C0), so, after the external cavity mirror generation deformation, certain deviation will take place and become (x in corresponding facula mass center _C1, y _C1), if the focal length of respective lens is f, then required calibration slopes is

S _x＝(x _C1-x _C0)/f，S _y＝(y _C1-y _C0)/f；

What cause the β drift is exocoel Z axial deformation, so, when drift value is Δ β,,, then only need make reflecting surface in the axial backwards rotation of corresponding Z if its distance to the symmetrical center line of two-way drift is l for a bit any on the exocoel mirroring face

δ _z＝(l/2)*Δβ；

Just can compensate the drift of a direction.

Thereby, for CCD1 sensor parameter counterparty to exocoel deformation, obtain desired parameters at processor, and calculate S in real time _xAnd S _yAfter, note directions X external cavity mirror length is 2a, promptly represents half of directions X external cavity mirror length with symbol a, then presses

δ _z＝(ω _aa)*(ω _xS _x+ω _y*S _y)/2

Calculate required compensation rate, in the formula, 2a is a directions X external cavity mirror length, ω _x, ω _y, ω _aBe the corresponding s of difference _x, s _y, a the precision performance weighted value, with the deformation quantity of external cavity mirror both direction and compensate crosslinked relevantly, this is that half amount compensation rate is obtained the key that method is known compensation rate.

Because when not applying driving voltage, the piezoelectricity compensator does not expand, the laser beam center that projects on the 4 quadrant detector overlaps with the 4 quadrant detector center, respective differences streaming current response I _z=0; But when applying driving voltage V _cThe time, the laser beam center that projects on the 4 quadrant detector will separate certain distance δ with the 4 quadrant detector center _z, the response of respective differences streaming current

$I_z=\left(\sqrt{8}{I}_c{C}_z{\mathrm{\δ}}_z\right)/\left(\mathrm{\π}{r}_z\right),$

I in the formula _cFor projecting the laser intensity on the 4 quadrant detector, r _zBe beam radius, C _ZIt is the detector photoelectric conversion efficiency.After filter, integrator, amplifier etc. are handled, I _zCan be converted into voltage V _z, as suitably choosing along separate routes steady modular system parameter, V _zCan with corresponding δ _zVoltage V _cEquating, is A as amplification coefficient _c, integral coefficient is C _I, piezoelectricity compensator transfer function is G _Z(s), then

V _z(s)＝V _c(s)＝A _cI _z(s)/d(s)，

In the formula,

d(s)＝C _I+I _z(s)A _cG _z(s)/δ _z(s)；

As seen, to certain piezoelectricity compensator, δ _zWith _VThe relation of c is certain, can measure in advance and be stored in the processor, to serve the required bucking voltage V of real time computation system _zThereby the piezoelectricity compensator compensates β required driving voltage that drifts about can contrast δ _zCalculate, and under processor, D/A, high drive module etc. cooperate, finish compensating operation.

During concrete the operation, β by R2.1, CCD1, processor 1, supporting D/A, high drive module 1, supporting piezoelectricity compensator, finishes corresponding S a direction drift _x, S _y, δ _z, V _zAbout sense operation and compensating operation; β by R2.2, CCD2, processor 2, supporting D/A, corresponding high drive module 2, supporting piezoelectricity compensator, finishes corresponding S in another direction drift _x, S _y, δ _z, V _zAbout sense operation and compensating operation

Beneficial effect of the present invention: the separate type ultra-large power semiconductor array cavity distortion compensation rate that the present invention provides is obtained technology, itself and supporting exocoel The deformation compensation technique is the 1/4Talbot external cavity mirror technology of servo inclination λ/2d together, overcomes well external cavity mirror deformation and is listed as to ultra large power two-dimensional semiconductor The phase-locked impact that brings of battle array can stably be shaken in the homophase mould array, and the adaptability of working environment is enhanced.

Claims (1)

1, a kind of exocoel deformation compensation rate acquisition methods of serving the Stability Control of ultra-high power semiconductor array selection homophase mould operation, it is characterized in that: in exocoel, make up and survey Compensation subsystem, obtain method and know compensation rate by partly measuring compensation rate, the 1/4talbot external cavity mirror is β at the angle of inclination of slow-axis direction, and β=λ/2d, λ is the work centre wavelength in the following formula, d is the slow axis array cycle, send He-Ne laser by active sensing light source, through first spectroscope described laser is divided into two, reverberation wherein is by first mirror reflects, the coupling beam expanding lens expands bundle, is projected on the described external cavity mirror reflecting surface by the reflection of second spectroscope again, is penetrated second spectroscope by the external cavity mirror beam reflected, through second speculum and the 3rd mirror reflects, after the 4th mirror reflects, regulate through zoom optics again, focus on and image on the charge coupled device from that part of He-Ne laser of second speculum, obtain a hot spot, calculate this facula mass center by processor; When deformation does not take place in external cavity mirror, calculate facula mass center on the charge coupled device by processor, be designated as (x _C0, y _C0), after external cavity mirror generation deformation, calculate facula mass center on the charge coupled device by processor again, be designated as (x _C1, y _C1), processor real-time calculates the difference of the facula mass center before and after the external cavity mirror generation deformation, is designated as (x _C1-x _C0) and (y _C1-y _C0) two components, thereby obtain the deformation data of a direction of external cavity mirror, and the difference of the facula mass center before and after the external cavity mirror generation deformation is when reaching thresholding, obtain method and know the required compensation rate of deformation on the compensation external cavity mirror deformation direction by partly measuring compensation rate, and then cooperation digital to analog converter and high drive module, drive installation is at the piezoelectricity compensator expansion compensation of described external cavity mirror terminal position, thus the drift of timely compensation external cavity mirror angle of inclination beta on the deformation direction.

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