Disclosure of Invention
The purpose of the invention is: aiming at the problems that the common-path and non-common-path static aberration in space optical communication can cause the correction capability of a deformable mirror to be obviously reduced, the communication error rate is increased, the tracking effect is poor, and the quality of a transmitting signal and a beacon light beam is poor, the method for correcting the total-path static aberration in the space optical communication miniaturized terminal is provided.
The technical scheme adopted by the invention for solving the technical problems is as follows:
a method for correcting all-optical-path static aberration in a space optical communication miniaturized terminal comprises the following steps:
the method comprises the following steps: constructing an all-optical-path module, wherein an all-optical-path system comprises five optical paths:
a first optical path: the incident light sequentially passes through the telescope, the tracking and aiming system and the piezoelectric deformable mirror, the beacon light passing through the piezoelectric deformable mirror is contracted after passing through the first beam splitter, and the contracted light enters the summer-Hartmann wavefront detector;
and a second light path: the incident light sequentially passes through the telescope, the tracking and aiming system and the piezoelectric deformable mirror, the beacon light passing through the piezoelectric deformable mirror enters the second beam splitter after passing through the first beam splitter, and the beacon light output by the second beam splitter enters the CCD2 after being output by the focusing lens;
and a third light path: the incident light sequentially passes through the telescope, the tracking and aiming system and the piezoelectric deformable mirror, the beacon light passing through the piezoelectric deformable mirror enters the second beam splitter after passing through the first beam splitter, and the beacon light entering the second beam splitter enters the avalanche photodiode after sequentially passing through the third beam splitter, the focusing lens and the multimode fiber;
and (4) a light path is as follows: the local signal light source sequentially passes through the focusing lens, the fourth beam splitter, the third beam splitter, the second beam splitter, the first beam splitter, the piezoelectric deformable mirror, the tracking and aiming system and the telescope and then is emitted;
and (5) an optical path five: the local beacon light source sequentially passes through the focusing lens, the fourth beam splitter, the third beam splitter, the second beam splitter, the first beam splitter, the piezoelectric deformable mirror, the tracking and aiming system and the telescope and then is emitted;
step two: all-optical path system based on construction measures delta respectively 1 、δ 2 、δ 3 、δ 4 And delta 5 Wherein, δ 1 、δ 2 、δ 3 、δ 4 、δ 5 Respectively carrying out complete light path total wave front detection measurement corresponding to light paths from one to five;
step three: according to delta 1 、δ 2 、δ 3 、δ 4 And delta 5 In combination with the formula delta i =Au i To obtain u 1 、u 2 、u 3 、u 4 And u 5 Wherein A is the response matrix of the piezoelectric deformable mirror, u 1 、u 2 、u 3 、u 4 、u 5 Initial piezoelectric deformable mirror control voltages corresponding to the complete light path are respectively from the first light path to the fifth light path;
step four: according to u 1 、u 2 、u 3 、u 4 、u 5 Controlling the voltage of the piezoelectric deformable mirror to finish aberration correction;
the second step comprises the following specific steps:
step two, firstly: the local signal light source and the local beacon light source are closed, the telescope receives the opposite incident light, and the difference between the total wave forward measurement of the complete light path corresponding to the light path I and the total wave forward measurement of the complete light path corresponding to the light path II, namely delta, is measured 1 -δ 3 ;
Step two: the telescope does not receive the opposite incident light any more, then the local signal light source is started, then the angle reflector is arranged at the emergent end of the telescope, so that the local signal light is emergent from the telescope through the light path IV, then the local signal light is reflected by the angle reflector, returns through the original path, enters the telescope again, is finally received by the light path III, and then the sum of the complete light path total wave front detection measurement corresponding to the light path IV and the complete light path total wave front detection measurement corresponding to the light path III, namely delta, is measured 4 +δ 3 ;
Step two and step three: turn off the local signal light source, turn on the local beacon light sourceThe far mirror still faces the corner reflector, so that the local beacon light is emitted from the telescope, returns to the original path after being reflected by the corner reflector, finally enters the telescope, is received by the light path II, and then the sum of the complete light path total wave front detection measurement corresponding to the light path five and the complete light path total wave front detection quantity corresponding to the light path I and the sum of the complete light path total wave front detection measurement corresponding to the light path five and the complete light path total wave front detection measurement corresponding to the light path II, namely delta 5 +δ 1 And delta 5 +δ 2 ;
Step two, four: turning off the local signal light source and turning on the local beacon light source, replacing the angle reflector with a phase conjugate mirror, applying no voltage to a deformable mirror, enabling the local beacon light to be emitted from the telescope through a light path five, then returning through the original path after being reflected by the phase conjugate mirror, finally receiving by a light path two, and then measuring the sum of the complete light path total wave front detection measurement corresponding to the negative light path five and the complete light path total wave front detection measurement corresponding to the light path one, namely-delta 5 +δ 1 ;
Step two and step five: d, converting-delta obtained in the second step or the fourth step 5 +δ 1 Delta obtained from step two or three 5 +δ 2 And delta 5 +δ 1 Simultaneous formation of delta 1 、δ 2 、δ 5 Then delta will be 1 Substituting the result of the first step into the result of the second step to obtain delta 3 Finally, will delta 3 Substituting the result of the second step into the result of the second step to obtain delta 4 To obtain delta 1 、δ 2 、δ 3 、δ 4 And delta 5 。
The invention has the beneficial effects that:
the utility model discloses a utilize subtend incident light, the static aberration correction technique of full light path of corner reflector and phase conjugation speculum, control deformable mirror produces specific initial compensation face type, can compensate the static aberration of sharing the light path with all non-sharing the light path simultaneously effectively, receive and the transmission signal with guaranteeing communication terminal simultaneously, these four functions of beacon light are not influenced, and then avoid because the deformable mirror correction ability that sharing the light path in the space optical communication and non-sharing the static aberration of light path lead to obviously descends, communication error rate increase, the tracking effect is poor, the problem that transmission signal and beacon light beam quality are poor.
Detailed Description
It should be noted that, in the case of conflict, the various embodiments disclosed in the present application may be combined with each other.
The first specific implementation way is as follows: specifically, the present embodiment is described with reference to fig. 1, and the method for correcting the total optical path static aberration in the miniaturized terminal for space optical communication according to the present embodiment includes the steps of:
the method comprises the following steps: constructing an all-optical-path module, wherein an all-optical-path system comprises five optical paths:
a first optical path: incident (beacon light) sequentially passes through a telescope, a tracking system and a piezoelectric deformable mirror, the beacon light after passing through the piezoelectric deformable mirror is contracted through a first beam splitter and then enters a summer-Hartmann wavefront detector;
and a second light path: the incident light sequentially passes through the telescope, the tracking and aiming system and the piezoelectric deformable mirror, the beacon light passing through the piezoelectric deformable mirror enters the second beam splitter after passing through the first beam splitter, and the beacon light output by the second beam splitter enters the CCD2 after being output by the focusing lens;
and a third light path: the incident light sequentially passes through the telescope, the tracking system and the piezoelectric deformable mirror, the beacon light passing through the piezoelectric deformable mirror enters the second beam splitter after passing through the first beam splitter, and the beacon light entering the second beam splitter sequentially passes through the third beam splitter, the focusing lens and the multimode optical fiber and then enters the avalanche photodiode;
and (4) a light path is as follows: the local signal light source sequentially passes through the focusing lens, the fourth beam splitter, the third beam splitter, the second beam splitter, the first beam splitter, the piezoelectric deformable mirror, the tracking and aiming system and the telescope and then is emitted;
and a light path five: the local beacon light source sequentially passes through the focusing lens, the fourth beam splitter, the third beam splitter, the second beam splitter, the first beam splitter, the piezoelectric deformable mirror, the tracking system and the telescope and then is emitted;
step two: all-optical path system based on construction measures delta respectively 1 、δ 2 、δ 3 、δ 4 And delta 5 Wherein, δ 1 、δ 2 、δ 3 、δ 4 、δ 5 Respectively carrying out complete light path total wave front detection measurement corresponding to light paths from one to five;
step three: according to delta 1 、δ 2 、δ 3 、δ 4 And delta 5 And combined with the formula delta i =Au i To obtain u 1 、u 2 、u 3 、u 4 And u 5 Wherein A is the response matrix of the piezoelectric deformable mirror, u 1 、u 2 、u 3 、u 4 、u 5 Initial piezoelectric deformable mirror control voltages corresponding to the complete optical path are respectively applied to the optical paths from the first optical path to the fifth optical path;
step four: according to u 1 、u 2 、u 3 、u 4 、u 5 Controlling the voltage of the piezoelectric deformable mirror to finish aberration correction;
the second step comprises the following specific steps:
step two is as follows: the local signal light source and the local beacon light source are closed, the telescope receives the opposite incident light, and the difference between the total wave forward measurement of the complete light path corresponding to the light path I and the total wave forward measurement of the complete light path corresponding to the light path II, namely delta, is measured 1 -δ 3 ;
Step two: the telescope does not receive the opposite incident light any more, then the local signal light source is started, then the angle reflector is arranged at the emergent end of the telescope, so that the local signal light is emergent from the telescope through the light path IV, then the local signal light is reflected by the angle reflector, returns through the original path, enters the telescope again, is finally received by the light path III, and then the sum of the complete light path total wave front detection measurement corresponding to the light path IV and the complete light path total wave front detection measurement corresponding to the light path III, namely delta, is measured 4 +δ 3 ;
Step two and step three: turning off the local signal light source, turning on the local beacon light source, making the telescope still face the corner reflector, making the local beacon light come out from the telescope, returning to the original path after being reflected by the corner reflector, entering the telescope again, finally being received by the light path two, then measuring the sum of the complete light path total wave front detection measurement corresponding to the light path five and the complete light path total wave front detection quantity corresponding to the light path one, and the sum of the complete light path total wave front detection measurement corresponding to the light path five and the complete light path total wave front detection measurement corresponding to the light path two, namely delta 5 +δ 1 And delta 5 +δ 2 ;
Step two, four: turning off the local signal light source and turning on the local beacon light source, replacing the angle reflector with a phase conjugate mirror, applying no voltage to a deformable mirror, enabling the local beacon light to be emitted from the telescope through the light path five, then returning to the telescope through the original path after being reflected by the phase conjugate mirror, finally being received by the light path two, and then measuring the sum of the complete light path total wave front detection measurement corresponding to the negative light path five and the complete light path total wave front detection measurement corresponding to the light path one, namely-delta 5 +δ 1 ;
Step two, five: d, converting-delta obtained in the second step or the fourth step 5 +δ 1 Delta obtained from step two or three 5 +δ 2 And delta 5 +δ 1 Simultaneous obtaining of delta 1 、δ 2 、δ 5 Then delta will be 1 Substituting the result of the first step into the result of the second step to obtain delta 3 Finally, delta will be 3 Substituting the result of the second step into the result of the second step to obtain delta 4 To obtain delta 1 、δ 2 、δ 3 、δ 4 And delta 5 。
The second embodiment is as follows: this embodiment mode is further described with respect to the first embodiment mode, and the difference between this embodiment mode and the first embodiment mode is that the specific steps of the second step are:
step two is one: applying an initial voltage u to the piezoelectric deformable mirror electrode 0 ={0,0,...0};
Step two, two: the received power P of the avalanche photodiode is read, and an evaluation function J is calculated by the formula J-P k (u k ) P, where J is an evaluation function, k denotes the k-th iteration result, and u denotes the piezoelectric deformable mirror control voltage vector;
step two, step three: randomly generating disturbance vector delta u satisfying Bernoulli distribution k ;
Step two, step four: respectively applying positive one-half disturbance vector delta u to the electrodes of the piezoelectric deformable mirror
k And negative one-half disturbance vector δ u
k Then, the received power P of the avalanche photodiodes is read, and an evaluation function is calculated by the formula J ═ P
And
step two, step one and step five: according to J
k And
obtaining the change delta J of the evaluation function
k :
Step two, step one and step six: according to the disturbance vector delta u k And the change of evaluation function δ J k To obtain u k+1 ;
Step two, step one and step seven: judging the value of k, if k is greater than 500 executing the steps of two-eight, if k is less than 500, making u k =u k+1 Repeating the step two one by one to the step two one by six;
step two, step one and step eight: obtaining the sub-spot coordinate value of CCD1 in the shack-Hartmann wavefront detector, namely delta 1 -δ 3 。
The third concrete implementation mode: this embodiment mode is further described as a second embodiment mode, and the difference between this embodiment mode and the second embodiment mode is that the second step includes the following specific steps:
step two, step one: applying initial voltage u to piezoelectric deformable mirror electrode 0 ={0,0,...0};
Step two and step two: the received power P of the avalanche photodiode is read, and an evaluation function J is calculated by the formula J-P k (u k ) P, wherein J is an evaluation function, k represents a k-th iteration result, and u represents a piezoelectric deformable mirror control voltage vector;
step two, step three: randomly generating disturbance vector delta u satisfying Bernoulli distribution k ;
Step two, step four: respectively applying positive half of disturbance vector delta u to electrodes of piezoelectric deformable mirror
k And negative one-half disturbance vector δ u
k Then, the received power P of the avalanche photodiodes is read, and an evaluation function is calculated by the formula J-P
And
step two, step five: according to
And
obtaining the change delta J of the evaluation function
k :
Step two, step six: according to the disturbance vector delta u k And the change δ J of the evaluation function k To obtain u k+1 ;
Step two, step seven: judging the value of k, if k is more than 500 executing step twenty-eight, if k is less than 500, making u k =u k+1 Repeating the first step to the second step;
step two, two and eight: obtaining the sub-spot coordinate value of CCD1 in the shack-Hartmann wavefront detector, namely delta 4 +δ 3 。
The fourth concrete implementation mode is as follows: this embodiment is a further description of a third specific embodiment, and the difference between this embodiment and the third specific embodiment is that the specific steps in the second and third steps are:
step two, step three and step one: the sub-facula coordinate value of the CCD in the shack-Hartmann wavefront detector is obtained without applying voltage to the piezoelectric deformable mirror, namely the sub-facula coordinate value is delta 5 +δ 1 ;
Step two, step three, step two: applying initial voltage u to piezoelectric deformable mirror electrode 0 ={0,0,...0};
Step two and step three: calculating evaluation function J by using pixel points on CCD2 k (u k ) Wherein, in the step (A),
I
i is the center of the CCD2 disk, I
i Diameter of
λ is the wavelength of the beacon light, λ is 808nm, f is the focal length of the front lens of the CCD2, f is 20mm, D is the aperture of the lens, D is 10mm, I
o Removing the disc center I from CCD2
i Circular ring of (I)
o Has a diameter of
Step two, step three and step four: randomly generating disturbance vector delta u satisfying Bernoulli distribution k ;
Step two, step three and step five:respectively applying positive one-half disturbance vector delta u to the electrodes of the piezoelectric deformable mirror
k And negative one-half disturbance vector δ u
k Then, the received power P of the avalanche photodiodes is read, and an evaluation function is calculated by the formula J ═ P
And
step two, step three and step six: according to
And
obtaining the variation delta J of the evaluation function
k :
Step two, pseudo-ginseng: according to the disturbance vector delta u k And the change of evaluation function δ J k To obtain u k+1 ;
Step two, step three and step eight: judging the value of k, if k is greater than 500 executing the step two, three and eight, if k is less than 500, making u k =u k+1 Repeating the second step, the second step and the third step;
step two, step three and step nine: obtaining the sub-spot coordinate value of CCD1 in the shack-Hartmann wavefront detector, namely delta 5 +δ 2 。
The fifth concrete implementation mode: the fourth embodiment is a further description of the fourth embodiment, and the difference between the fourth embodiment and the fourth embodiment is that in the second or fourth step, no voltage is applied to the deformable mirror, and the sub-spot coordinate value of the CCD1 in the shack-hartmann wavefront sensor is obtained, that is, the sub-spot coordinate value is- δ 5 +δ 1 。
The sixth specific implementation mode: this embodiment is a further description of a fifth embodiment, and is different from the fifth embodiment in that the change δ J of the evaluation function is k Expressed as:
the seventh embodiment: this embodiment mode is a further description of a sixth embodiment mode, and the difference between this embodiment mode and the sixth embodiment mode is that u is described above k+1 Expressed as:
u k+1 =u k -γδJ k δu k
where γ is a gain factor.
The specific implementation mode is eight: this embodiment is a further description of a seventh embodiment, and the difference between this embodiment and the seventh embodiment is that the piezoelectric deformable mirror includes 43 electrodes, including 40 electrodes and 3 independent pitch/tilt electrodes on the main mirror.
The specific implementation method nine: this embodiment is further described with respect to the eighth embodiment, and the difference between this embodiment and the eighth embodiment is that the specific step of the fourth step is:
voltage u 'of electrode 1 to 8' 1~8 =(u′ 3 [1∶8]+u′ 4 [1∶8])/2;
Voltage u 'of electrode 9 to 40' 9~40 =(u′ 1 [9∶40]+u′ 2 [9∶40]+u′ 5 [9∶40])/3;
Voltage u 'of pitch/tilt electrode 1 to 3' tip-tilt =u′ 3 [41∶43]。
The specific implementation mode is ten: the present embodiment is further described with respect to the ninth embodiment, and the differences between the present embodiment and the ninth embodiment are that the detection waveband of the shack-hartmann wavefront detector is 400 to 900nm, the aperture is 4.5mm, the number of microlenses is less than or equal to 700, the size is 150 μm, and the focal length is 10 mm.
The schematic diagram of the optical path of the spatial optical communication terminal is shown in fig. 1, and the common optical path is an optical path which all light has undergone before entering a beam splitter BS1 and includes a telescope, a tracking system (laser communication tracking system) and the like; in the five non-common optical paths, the receiving optical path is (1) a beacon light wavefront detection optical path, (2) a beacon light receiving optical path, (3) a signal light receiving optical path, and the transmitting optical path is (4) a signal light transmitting optical path and (5) a beacon light transmitting optical path. In FIG. 1, DM is a deformable mirror, BS 1-BS 4 are four beam splitters, and SH-WFS is a shack-Hartmann wavefront sensor. The incident beacon light is split by a BS1 after passing through a telescope, a tracking system and a DM, one part of the incident beacon light is received by a light path (1), and the other part of the incident beacon light is received by a CCD2 (charge coupled device); the incident signal light is received by the optical path (3) through BS1, BS2, BS 3. Both the local signal light and the local beacon light exit sequentially through BS4, BS3, BS2, BS1, DM, the tracking system, and the telescope. The signal light is different from the beacon light wave band, and the light paths (1) to (4) are all provided with filter plates.
A schematic diagram of a full-light path static aberration correction device in a space optical communication miniaturized terminal is shown in fig. 2, angle reflectors and phase conjugate reflectors are respectively fixed in two directions of a telescope group, and the telescope group can be opposite to the angle reflectors or the phase conjugate reflectors by horizontally rotating.
The principle and operation of the device are described below. The common optical path and each non-common optical path form a complete optical path, and the complete optical path total wave front detection measurement (SH-WFS detection offset) corresponding to the optical paths (1) - (5) are respectively recorded as delta 1 、δ 2 、δ 3 、δ 4 、δ 5 And recording the initial deformable mirror control voltage u corresponding to the complete optical path of the optical paths (1) - (5) 1 、u 2 、u 3 、u 4 、u 5 ,u i [1∶40]Is the control voltage u of the actuator with serial number 1-40 on the main reflector i [41∶43]The individual actuator positions are shown in fig. 3 for the control voltages of the individual pitch/tilt actuator arms numbered 1, 2, 3. Control voltage u i (i-1, 2, 3, 4, 5) and wavefront measurement δ i (i is 1, 2, 3, 4, 5) has a definite mathematical relationship, such as formula (1), where a is a deformable mirror response matrix found in advance. The correction steps are as follows:
δ i =Au i (1)
measuring delta 1 -δ 3 : the communication terminal stops operating and receives the incident light, and as shown in fig. 4, the steps (1) to (8) are completed by using a computer.
Applying an initial voltage u to 43 electrodes of the deformable piezoelectric deformable mirror 0 ={0,0,...0};
The received power P of APD is read and an evaluation function J is calculated by the formula (2) k (u k )=-p;
J=-P(2)
Randomly generating a random perturbation vector delta u satisfying Bernoulli distribution k ={δu 1 ,δu 2 ,...δu 37 };
The received power P of APD is read, and an evaluation function is calculated by the formula (2)
And
calculating δ J by equation (3) k ;
δJ=J + -J - =J(u+δu/2)-J(u-δu/2) (3)
Calculating u by equation (4) k+1 ;
u k+1 =u k -γδ J kδu k (4)
Determining the value of k, stopping the cycle if k > 500, and making u if k < > 500 k =u k+1 Repeating the processes (1) to (6);
storing the optimized CCD1 sub-spot coordinates in a computer hard disk, namely delta 1 -δ 3 ;
Measuring delta 4 +δ 3 : the communication terminal no longer receives the opposite incident light, the local signal light is turned on, and the telescope group turns to the angle reflector, as shown in fig. 5. The signal light is emitted from the telescope through the light path (4), is reflected by the corner reflector, returns to the original path, enters the telescope again, and is finally received by the light path (3). And (3) completing the steps (1) to (8) by using a computer.
Applying an initial voltage u to 43 electrodes of a deformable piezoelectric deformable mirror 0 ={0,0,...0};
The received power P of APD is read and an evaluation function J is calculated by the formula (2) k (u k );
Randomly generating random disturbance vector delta u satisfying Bernoulli distribution k ={δu 1 ,δu 2 ,...δu 43 };
The received power P of the APD is read, and the evaluation function is calculated by the formula (2)
And
calculating δ J by equation (3) k ;
Calculating u by equation (4) k+1 ;
Determining the value of k, stopping the cycle if k > 500, and making u if k < > 500 k =u k+1 Repeating the processes (1) to (6);
the optimized CCD1 sub-spot coordinates are stored in the hard disk of the computer, and the angle reflector does not change the phase of the wave front, so that the quantity is delta 4 +δ 3 ;
Measuring delta 5 +δ 1 And delta 5 +δ 2 : the signal light is turned off and the beacon light is turned on, with the telescope still facing the corner mirror, as in fig. 6. The local beacon light is emitted from the telescope, reflected by the corner reflector, returned to the original path, enters the telescope again and is finally received by the light path (2). And (4) completing the steps (1) to (9) by using a computer.
The sub-light spot coordinates of the CCD1 are stored in the hard disk of the computer without applying voltage to the deformable mirror, namely delta 5 +δ 1 ;
Applying an initial voltage u to 43 electrodes of a deformable piezoelectric deformable mirror 0 ={0,0,...0};
Calculating an evaluation function J according to formula (5) by using pixel points on the CCD2
k (u
k ),I
i The center of the disk is the center of CCD and the diameter is
λ is the wavelength of the beacon light 800nm, f is the focal length of the front lens of the CCD2, and D is the lensPore diameter of 10mm, I
o Is of diameter of
The center is CCD center, I is removed
i A partial circular ring;
randomly generating a random perturbation vector delta u satisfying Bernoulli distribution k ={δu 1 ,δu 2 ,...δu 43 };
Calculating an evaluation function according to formula (3) by using pixel points on the CCD2
And
calculating δ J by equation (3) k ;
Calculating u by equation (1) k+1 ;
Judging the value of k, stopping iteration if k is more than 500, and making u if k is less than 500 k =u k+1 Repeating the processes (2) to (7);
storing the optimized CCD1 sub-spot coordinates in a computer hard disk, namely delta 5 +δ 2 。
Measuring-delta 5 +δ 1 And-delta 5 +δ 2 : still with the beacon light on, the telescope group turns to the phase conjugate mirror, as in fig. 7. The local beacon light is emitted from the telescope through the light path (5), returns through the original path after being reflected by the phase conjugate mirror, enters the telescope again and is finally received by the light path (2). The coordinates of the sub-spots of CCD1 are stored in the hard disk of computer without applying voltage to the deformable mirror, and the conjugate of the wavefront can be obtained by the phase conjugate mirror, and the quantity is-delta 5 +δ 1 。
Delta-obtained in step 4 5 +δ 1 Delta from step 3 5 +δ 2 And delta 5 +δ 1 Simultaneous determination of delta 1 、δ 2 、δ 5 . Then delta will be 1 Substituting the result of step 1 can also determine delta 3 Finally, will delta 3 Substituting the result of step 2to obtain δ 4 。
Through the steps 1 to 5, delta 1 、δ 2 、δ 3 、δ 4 、δ 5 All can be found out, and u can be obtained from the formula (1) 1 、u 2 、u 3 、u 4 、u 5 . Complex u 1 、u 2 、u 3 、u 4 、u 5 And giving an initial surface type of a final deformable mirror capable of balancing four optical path aberrations according to a certain rule as follows:
voltage u of actuator 1-8 1~8 =(u 3 [1∶8]+u 4 [1∶8])/2;
Voltage u of actuator 9-40 9~40 =(u 1 [9∶40]+u 2 [9∶40]+u 5 [9∶40])/3;
Voltage u of tilt actuator 1-3 tip-tilt =u 3 [41∶43]。
The wavefront aberrations received by the SH-WFS measurement optical paths (1) to (3) and the wavefront aberrations received by the measurement optical paths (4) and (5) can be used to obtain the improvement of 100 groups of random wavefront RMS values as shown in FIGS. 8 to 12,
the specific implementation scheme of the all-optical-path aberration correction device in the space optical communication miniaturized terminal is as follows:
the corner reflector is a hollow retroreflector of Thorlab corporation model HRR202-P01 with an entrance aperture of
Inch, silver film coated with a protective layer, each surface R for a wavelength of 450nm-2 μm
avg > 97.5%, the retroreflected beam is deflected by less than 20 arcseconds.
The deformable mirror is a deformable piezoelectric deformable mirror with the model number of DMH40-P01 of Thorlab company, a silver film with a protective layer, the working wave band is 450nm-20 μm,
pupil, with large stroke, highest refresh rate of 4kHz, 43 actuators (40 actuators on the main mirror and 3 independent pitch/tilt actuator arms). .
The SH-WFS selects a wavefront detector with the model of UI-2210M of OKO company, the detection type is CCD detection, the detection wave band is 400-900 nm, the caliber is 4.5mm, the number of micro lenses is less than or equal to 700, the size is 150 mu M, and the focal length is 10 mm.
The test computer is a computer server, the CPU is i 74630K (6x3.4Ghz avec 12Mo LLC, 2Mo L2total), the mainboard ASUS X79-DELUXE, the hard disk SAMSUNG SSD 840PRO 256GB, the graphics card is GAINWARD GEFORCE GT7302GB DDR3 SILENT FX, and the memory is GSKILL16GB (4X4) QUAD CHANNEL F3-14900CL9Q-16 GBZL.
The phase conjugate reflector was a hollow retroreflector array of type AR-60 available from Hao volume photoelectricity corporation with a retroreflector count of 60 and a maximum deviation of 5.0 or 20.0 arcsec.
The beacon light source uses a laser diode with model number ML620G40, wavelength of 808nm, output optical power of 150mw, typical drive current of 180mA, maximum 220mA, and size of
The signal light uses a laser diode of model FPL1001C, the wavelength is 1550nm, the output optical power is 150mw, the typical driving current is 400mA, and the maximum driving current is 500 mA.
The detector uses an avalanche photodiode with the model of APD310, the detection waveband is 850-1650nm, the 3dB bandwidth is 5-1000MHz, and the responsivity is 0.9A/W under the wavelength of 1550 nm.
It should be noted that the detailed description is only for explaining and explaining the technical solution of the present invention, and the scope of protection of the claims is not limited thereby. It is intended that all such modifications and variations be included within the scope of the invention as defined in the following claims and the description.