Adaptive optics system based on excitation light beacon

Abstract

The present invention provides an adaptive optical system based on an excitation light beacon. The system uses the excitation light generated by laser heating or ablation on the target surface as the beacon of the adaptive optical system, which is received by a telescope device after being transmitted through the atmosphere and detected by a wavefront distortion detection device. After the wavefront information is solved by a computer, the wavefront distortion correction device is controlled to load the distorted wavefront conjugate phase to achieve correction of aberrations, which can achieve clear imaging of the target or improve the power density of the laser focus point; the beacon light of this system is generated at the target, which is suitable for target detection at various heights, and there is no problem of focusing anisotropy; in addition, the correction capability of this system has no requirements on the roughness of the target surface, and at the same time has the advantages of high closed-loop bandwidth of the adaptive optical technology based on wavefront detection.

Description

Technical Field

[0001] The present invention relates to the technical field of adaptive optics, and in particular to an adaptive optics system based on an excitation light beacon. Background Art

[0002] When adaptive optics is used to correct the aberration of laser atmospheric transmission, if the target is a non-cooperative target, it is often necessary to introduce artificial beacons to detect atmospheric aberrations. Conventional artificial beacons include Rayleigh beacons, sodium beacons, and active illumination beacons. However, limited by the generation mechanism of Rayleigh scattering and sodium resonance fluorescence scattering, Rayleigh beacons can only be generated in the stratosphere at about 20km, and the sodium beacon beam can only be focused in the sodium layer at an altitude of 90km to 100km. For targets not in these altitude segments, the aberration detected by the adaptive optics system will be different from the atmospheric link aberration of the actual target to the adaptive optics system, and focusing anisotropy will also occur. The invention patent with publication number CN105223691A proposes an adaptive optical correction device and method based on a sodium layer structured beacon. This method uses a structured sodium laser beam array method to solve the focusing anisotropy device and method, but this method is suitable for large-aperture ground-based telescope systems; at the same time, the method mentions that the use of multi-layer conjugate adaptive optical technology also reduces the focusing anisotropy to a certain extent, and the method requires multiple sub-beacons and matching Hartmann sensors, which greatly increases the complexity of the system and increases the cost. In addition, the above two methods do not solve the problem that the beacon and the target are not at the same height.

[0003] Active illumination beacons use scattered return light after laser illumination of the target to extract wavefront distortion. This method is not limited by the target height and does not have focusing anisotropy. It is widely used in near-ground and high-altitude laser transmission correction. However, the correction capability of the adaptive optical system using this method is restricted by the quality of the illumination laser and the surface roughness of the target. The paper "The Effect of Target Roughness Characteristics on Active Illumination Beacon Wavefront Detection" analyzes the effect of the target surface roughness on the uniformity of the scattered return light intensity and the RMS of the wavefront. The results show that as the target surface roughness decreases, the difference in the atmospheric turbulence aberration results obtained using the active illumination beacon and the point light source beacon becomes larger, and the beacon light detection error increases.

[0004] In view of this, it is necessary to design an adaptive optical system based on excitation light beacons to solve the above problems. Summary of the invention

[0005] In view of the defects of the above-mentioned prior art, the purpose of the present invention is to solve the problem of the lack of beacon light of non-cooperative targets in the adaptive optical system, and to use the excitation light generated by laser heating or ablation on the target surface as the beacon of the adaptive optical system. After being transmitted through the atmosphere, it is received by the telescope system and detected by the wavefront distortion detection device. After being processed by a computer, the wavefront distortion correction device is controlled to correct the wavefront distortion to achieve clear imaging of the target or improve the power density of the laser focus point.

[0006] To achieve the above object, the present invention provides an adaptive optical system based on an excitation light beacon, comprising:

[0007] A receiving unit, used for receiving the target excitation light and converting the focused light into parallel light;

[0008] A wavefront phase compensation correction unit, used for receiving the parallel light;

[0009] A beam splitter, used for receiving the light beam output by the wavefront phase compensation correction unit and splitting the light beam into two beams;

[0010] A wavefront distortion detection unit, used for receiving the first light beam output by the beam splitter and detecting the wavefront distortion information of the first light beam;

[0011] An imaging detection unit, used for receiving the second light beam output by the beam splitter and imaging the target;

[0012] The terminal is used to receive the wavefront distortion information calculated by the wavefront distortion detection unit and the image output by the imaging detection unit, and after processing, output control information to control the wavefront phase compensation correction unit to perform wavefront correction on the received light.

[0013] Furthermore, the wavefront distortion detection unit comprises:

[0014] a first converging lens, receiving the first light beam output by the beam splitter, and focusing the first light beam onto a wavefront distortion detector;

[0015] The wavefront distortion detector detects the wavefront distortion information of the received first light beam.

[0016] Furthermore, the imaging detection unit comprises:

[0017] A second converging lens receives the second light beam output by the beam splitter and focuses the light beam onto the CCD camera;

[0018] The CCD camera images the calibrated target; the image taken by the CCD camera is stored by the terminal.

[0019] Furthermore, the wavefront phase compensation correction unit comprises:

[0020] A first wavefront phase compensation correction device, used for receiving the parallel light, and receiving control information output by the terminal to control the optical path of the first wavefront phase compensation correction device to compensate and correct a part of the wavefront phase;

[0021] The second wavefront phase compensation correction device is used to receive the light beam output by the first wavefront phase compensation correction device, and simultaneously receive the control information output by the terminal to control the optical path of the second wavefront phase compensation correction device to perform partial wavefront phase compensation correction.

[0022] Further, the first wavefront phase compensation correction device includes a tilt mirror, and the tilt mirror receives control information output by the terminal to control the tilt angle of the tilt mirror;

[0023] The second wavefront phase compensation correction device includes a deformable mirror, and the deformable mirror receives control information output by the terminal to control the surface shape of the deformable mirror.

[0024] Furthermore, the wavefront distortion detection unit further includes a first filter; the reflected light generated by the beam splitter first passes through the first filter and is then converged by the first converging lens;

[0025] The imaging detection unit further includes a second filter; the transmitted light generated by the beam splitter first passes through the second filter and is then converged by the second converging lens.

[0026] The present invention also provides an adaptive optical system based on an excitation light beacon, comprising:

[0027] The transmitting and receiving unit is used to transmit the laser to the target, and after receiving the excitation light of the target, convert the focused light into parallel light;

[0028] A wavefront distortion correction unit, used for receiving the parallel light and for receiving the laser light transmitted by the dichroic mirror;

[0029] a dichroic mirror, used for reflecting the light beam output by the wavefront distortion correction unit and transmitting the laser light generated by the laser emitting device;

[0030] A wavefront distortion detection unit, used for receiving the light beam reflected by the dichroic mirror and detecting the wavefront distortion information of the reflected light beam;

[0031] The terminal is used to receive the wavefront distortion information calculated by the wavefront distortion detection unit, and after processing, output control information to control the wavefront distortion correction unit to perform wavefront correction on the received light.

[0032] Furthermore, the wavefront distortion detection unit comprises:

[0033] a first converging lens, receiving the light beam reflected by the dichroic mirror, and focusing the reflected light beam onto the wavefront distortion detector;

[0034] The wavefront distortion detector detects the wavefront distortion information of the received reflected light beam.

[0035] Furthermore, the wavefront distortion correction unit comprises:

[0036] A first wavefront phase compensation correction device, used for receiving the parallel light, and receiving control information output by the terminal to control the optical path of the first wavefront phase compensation correction device to compensate and correct a part of the wavefront phase;

[0037] A second wavefront phase compensation correction device, used for receiving the light beam output by the first wavefront phase compensation correction device, and receiving control information output by the terminal to control the optical path of the second wavefront phase compensation correction device to perform partial wavefront phase compensation correction;

[0038] The first wavefront phase compensation correction device includes a tilt mirror, and the tilt mirror receives control information output by the terminal to control the tilt angle of the tilt mirror;

[0039] The second wavefront phase compensation correction device includes a deformable mirror, and the deformable mirror receives control information output by the terminal to control the surface shape of the deformable mirror.

[0040] Furthermore, the wavefront distortion detection unit also includes a first filter; the light beam reflected by the dichroic mirror first passes through the first filter and then is converged by the first converging lens.

[0041] The beneficial effects of the present invention are:

[0042] The present invention provides an adaptive optical system based on an excitation light beacon, which uses the excitation light generated by laser heating or ablation on the target surface as the beacon of the adaptive optical system, which is received by a telescope device after being transmitted through the atmosphere and detected by a wavefront distortion detection device, and the wavefront distortion correction device is controlled to load the distorted wavefront conjugate phase after the wavefront information is solved by a computer to correct the aberration, thereby achieving clear imaging of the target or improving the power density of the laser focus point. Compared with the traditional Rayleigh guide star or sodium guide star beacon solution, the beacon light of this system is generated at the target, is not limited by the target height, is suitable for target detection at various heights, and does not have the problem of focusing anisotropy; compared with the illumination beacon solution, the correction capability of this system has no requirements on the roughness of the target surface, is suitable for a variety of target materials and surface roughness, and does not require a complex illumination laser system, and has advantages in both applicability and system complexity; at the same time, it also has the advantages of high closed-loop bandwidth of adaptive optical technology based on wavefront detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 A schematic diagram of an adaptive optical system based on an excitation light beacon provided in Example 1 of the present invention;

[0044] Figure 2 This is a schematic diagram of an adaptive optical system based on an excitation light beacon provided in Example 2 of the present invention.

[0045] Reference numerals

[0046] 1. Laser emitting device; 21. Telescope; 22. Collimating lens; 311. Spectroscope; 312. Color separation mirror; 32. First filter; 33. First converging lens; 34. Wavefront distortion detector; 35. Computer; 41. Tilt mirror; 42. Deformable mirror; 43. Second filter; 44. Second converging lens; 45. CCD camera. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0048] In addition, it should be noted that the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0049] like Figure 1 As shown, an adaptive optical system based on an excitation light beacon includes: a receiving unit, used to receive target excitation light and convert the focused light into parallel light;

[0050] A wavefront phase compensation correction unit, used for receiving the parallel light;

[0051] A beam splitter 311 is used to receive the light beam output by the wavefront phase compensation correction unit and split the light beam into two beams;

[0052] a wavefront distortion detection unit, configured to receive the first light beam output by the beam splitter 311 and detect wavefront distortion information of the first light beam;

[0053] An imaging detection unit, used to receive the second light beam output by the beam splitter 311 and to image the target;

[0054] The terminal is used to receive the wavefront distortion information calculated by the wavefront distortion detection unit and the image output by the imaging detection unit, and after processing, output control information to control the wavefront phase compensation correction unit to perform wavefront correction on the received light.

[0055] Specifically, in some embodiments of the present invention, the wavefront distortion detection unit includes:

[0056] A first converging lens 33 receives the first light beam output by the beam splitter 311 and focuses the first light beam onto a wavefront distortion detector 34;

[0057] The wavefront distortion detector 34 detects the wavefront distortion information of the received first light beam.

[0058] Specifically, in some embodiments of the present invention, the imaging detection unit includes:

[0059] A second converging lens 44 receives the second light beam output by the beam splitter 311 and focuses the light beam onto the CCD camera 45;

[0060] The CCD camera 45 images the calibrated target; the image captured by the CCD camera 45 is stored by the terminal.

[0061] Specifically, in some embodiments of the present invention, the wavefront phase compensation correction unit includes:

[0062] A first wavefront phase compensation correction device, used for receiving the parallel light, and receiving control information output by the terminal to control the optical path of the first wavefront phase compensation correction device to compensate and correct a part of the wavefront phase;

[0063] The second wavefront phase compensation correction device is used to receive the light beam output by the first wavefront phase compensation correction device, and simultaneously receive the control information output by the terminal to control the optical path of the second wavefront phase compensation correction device to perform partial wavefront phase compensation correction.

[0064] Specifically, in some embodiments of the present invention, the first wavefront phase compensation correction device includes a tilt mirror 41, and the tilt mirror 41 receives control information output by the terminal to control the tilt angle of the tilt mirror 41;

[0065] The second wavefront phase compensation correction device includes a deformable mirror 42 , and the deformable mirror 42 receives the control information output by the terminal to control the surface shape of the deformable mirror 42 .

[0066] Specifically, in some embodiments of the present invention, the wavefront distortion detection unit further includes a first filter 32 ; the reflected light generated by the beam splitter 311 first passes through the first filter 32 and then is converged by the first converging lens 33 .

[0067] Specifically, in some embodiments of the present invention, the imaging detection unit further includes a second filter 43 ; the transmitted light generated by the beam splitter 311 first passes through the second filter 43 and then is converged by the second converging lens 44 .

[0068] Specifically, in some embodiments of the present invention, the receiving unit includes a telescope 21 and a collimating lens 22 ; and the terminal includes a computer 35 .

[0069] The adaptive optical correction method using the adaptive optical system as described above is as follows: the high-energy laser generated by the laser emitting device 1 is focused on the target surface through the focusing component in the laser emitting device 1, so that the temperature of the target surface is increased or ablated, and a spectrum is excited; wherein the radiation spectrum generated by the high-energy laser irradiating the target includes a thermal radiation spectrum, a Raman spectrum and a plasma spectrum; the spectrum includes target excitation light and target image information. The target excitation light and the target image information are received and converged by the telescope 21, and converted into parallel beams by the collimating lens 22. The received return light is then refracted by the tilt mirror 41 and the deformable mirror 42 in turn and irradiated to the beam splitter 311. The beam splitter 311 divides the light into reflected light and transmitted light; after the reflected light generated by the beam splitter 311 passes through the first filter 32 to extract the excitation light signal of a specific wavelength, the position of the first converging lens 33 is adjusted so that the focused light spot is completely received by the wavefront distortion detector 34; the wavefront distortion detector 34 transmits the collected image information to the computer 35; at the same time, the transmitted light generated by the beam splitter 311 passes through the second filter 43 and the second converging lens 44 in sequence, and is imaged on the CCD camera 45 and transmitted to the computer 35; the computer 35 solves The wavefront distortion information is obtained, converted into a driver control signal after processing, and then transmitted to the tilt mirror 41 and the deformable mirror 42 respectively to generate a conjugate distorted wavefront phase, which offsets the wavefront distortion phase, thereby realizing adaptive optical correction (the tilt mirror 41 corrects the tilt phase difference by changing the tilt angle, and the deformable mirror 42 corrects the remaining high-order phase difference by changing the surface shape, so that the change in the distorted light wave can be comprehensively changed only by adjusting these two); then, the received return light passes through the beam splitter 311, and then continues to repeat for the next adjustment until the adaptive optical system completes the correction of imaging clarity.

[0070] In this arrangement, the laser emitted by the laser emitting device 1 is used to heat or ablate the target surface to excite the light as the beacon light source of the adaptive optical system. After being transmitted through the atmosphere, it is received by the telescope device and detected by the wavefront distortion detection device. Finally, the computer 35 controls the wavefront distortion correction device to perform wavefront correction on the received light, thereby realizing a closed-loop correction adaptive optical system for wavefront distortion and improving the adaptive optical correction capability.

[0071] Specifically, in some embodiments of the present invention, the wavefront distortion detector 34 includes a Hartmann sensor.

[0072] With such arrangement, by adopting the Hartmann sensor, the whole system has a compact structure, a large dynamic measurement range, a high sampling frequency, a high light energy utilization rate, is insensitive to vibration, and does not have the 2π uncertainty problem.

[0073] Specifically, in some embodiments of the present invention, the deformable mirror 42 includes a continuous surface discretely driven deformable mirror.

[0074] When the deformable mirror 42 is a continuous surface discretely driven deformable mirror, if the driving processes of each driver are independent of each other, the influence of the surface shape of the entire deformable mirror 42 on the wavefront phase distribution of the light field is regarded as a linear combination of the influence of each driver on the light field:

[0075] in, L ——the total number of actuators on the deformable mirror,

[0076] v j ——No. j The voltage applied to the driver,

[0077] D j ( x , y )——In the j The influence function of each driver.

[0078] In high-power solid-state laser devices, the influence function of the actuator on the continuous surface discrete drive deformable mirror is a Gaussian function or a super-Gaussian function, expressed as:

[0079]

[0080] in, a ——driver cross-link value,

[0081] d - the distance between the actuators,

[0082] α ——Gaussian function order.

[0083] With this arrangement, the use of discrete piezoelectric drive allows the entire system to have the advantages of high resolution, large dynamic correction range, and easy processing.

[0084] like Figure 2 As shown, an adaptive optical system based on an excitation light beacon comprises:

[0085] The transmitting and receiving unit is used to transmit the laser to the target, and after receiving the excitation light of the target, convert the focused light into parallel light;

[0086] A wavefront distortion correction unit, used for receiving the parallel light and for receiving the laser light transmitted by the dichroic mirror 312;

[0087] A dichroic mirror 312, used for reflecting the light beam output by the wavefront distortion correction unit and transmitting the laser light generated by the laser emitting device 1;

[0088] A wavefront distortion detection unit, used for receiving the light beam reflected by the dichroic mirror 312, and detecting the wavefront distortion information of the reflected light beam;

[0089] The terminal is used to receive the wavefront distortion information calculated by the wavefront distortion detection unit, and after processing, output control information to control the wavefront distortion correction unit to perform wavefront correction on the received light.

[0090] Specifically, in some embodiments of the present invention, the wavefront distortion detection unit includes:

[0091] A first converging lens 33 receives the light beam reflected by the dichroic mirror 312 and focuses the reflected light beam onto the wavefront distortion detector 34;

[0092] The wavefront distortion detector 34 detects the wavefront distortion information of the received reflected light beam.

[0093] Specifically, in some embodiments of the present invention, the wavefront distortion correction unit includes:

[0094] A first wavefront phase compensation correction device, used for receiving the parallel light, and receiving control information output by the terminal to control the optical path of the first wavefront phase compensation correction device to compensate and correct a part of the wavefront phase;

[0095] A second wavefront phase compensation correction device, used for receiving the light beam output by the first wavefront phase compensation correction device, and receiving control information output by the terminal to control the optical path of the second wavefront phase compensation correction device to perform partial wavefront phase compensation correction;

[0096] The first wavefront phase compensation correction device includes a tilt mirror 41, and the tilt mirror 41 receives control information output by the terminal to control the tilt angle of the tilt mirror 41;

[0097] The second wavefront phase compensation correction device includes a deformable mirror 42 , and the deformable mirror 42 receives the control information output by the terminal to control the surface shape of the deformable mirror 42 .

[0098] Specifically, in some embodiments of the present invention, the wavefront distortion detection unit further includes a first filter 32 ; the light beam reflected by the dichroic mirror 312 first passes through the first filter 32 and then is converged by the first converging lens 33 .

[0099] Specifically, in some embodiments of the present invention, the transmitting and receiving unit includes a telescope 21 and a collimating lens 22 ; and the terminal includes a computer 35 .

[0100] The adaptive optics correction method using the adaptive optics system as described above is as follows: the high-energy laser generated by the laser emitting device 1 passes through the dichroic mirror 312, and then is deflected by the deformable mirror 42 and the tilt mirror 41 in sequence, and then passes through the collimating lens 22 first, and then is emitted toward the target by the telescope 21, wherein the telescope 21 focuses the laser at the target by adjusting the focal length, so that the surface temperature of the target is increased or ablated, and a spectrum is excited. The excitation light generated by the target is then received and converged by the telescope 21, and converted into a parallel light beam by the collimating lens 22. The received return light is then deflected by the tilt mirror 41 and the deformable mirror 42 in sequence and then irradiated to the dichroic mirror 312. The dichroic mirror 312 reflects the received return light, and after the return light signal of a specific wavelength is extracted by the first filter 32, the position of the first converging lens 33 is adjusted so that the converged light spot is completely received by the wavefront distortion detector 34. The wavefront distortion detector 34 transmits the image information in the collected return light to the computer 35, and the computer 35 obtains the wavefront distortion information through calculation, and after processing, it is converted into a driver control signal and transmitted to the tilt mirror 41 and the deformable mirror 42 respectively to generate a conjugate distorted wavefront phase, which offsets the wavefront distortion phase, thereby realizing adaptive optical correction. Subsequently, the target image information scattered return light after wavefront correction passes through the dichroic mirror 312, and then passes through the first filter 32 and the first converging lens 33 in sequence, and continues to repeat for the next adjustment until the adaptive optical system completes the correction of imaging clarity.

[0101] With such a configuration, a common optical path design for laser emission and excitation light detection is adopted, and an adaptive optical system using excitation light as a beacon light source can effectively correct the phase distortion of laser transmission in the atmosphere and improve the laser focusing power density on the target. Since the laser transmission channel coincides with the wavefront distortion detection link, the thermal blooming effect caused by atmospheric transmission of high-energy lasers can be effectively corrected. In addition, the laser generated by the laser emitting device 1 is loaded with a conjugate distorted wavefront phase factor after passing through the tilt mirror 41 and the deformable mirror 42, which offsets the wavefront distortion generated by the atmosphere during atmospheric transmission, thereby realizing adaptive optical correction; the corrected laser has a smaller focusing spot at the target, and the spot power density is increased, which greatly improves the ablation effect on the target.

[0102] Specifically, in some embodiments of the present invention, the wavefront distortion detector 34 includes a Hartmann sensor.

[0103] With such arrangement, by adopting the Hartmann sensor, the whole system has a compact structure, a large dynamic measurement range, a high sampling frequency, a high light energy utilization rate, is insensitive to vibration, and does not have the 2π uncertainty problem.

[0104] Specifically, in some embodiments of the present invention, the deformable mirror 42 includes a continuous surface discretely driven deformable mirror.

[0105] With this arrangement, the use of discrete piezoelectric drive allows the entire system to have the advantages of high resolution, large dynamic correction range, and easy processing.

[0106] The following is an explanation of the working mode of a metasurface device and a design method thereof for a common aperture detection and emission scheme provided by the present invention:

[0107] Description: The laser emitting device 1 is used to generate a high-energy laser beam; the telescope 21 is used to receive the target excitation light; the collimating lens 22 is used to convert the focused light into parallel light; the beam splitter 311 is used to divide the light into reflected light and transmitted light, and is used for wavefront distortion detection and target imaging respectively; the color separation mirror 312 is used to transmit the laser generated by the laser emitting device 1, and is also used to reflect the received excitation light; the first filter 32 is used to filter the background stray light and extract the excitation light of a specific wavelength; the first converging lens 33 is used to focus the light beam to the wavefront distortion detector 34; the wavefront distortion detector 34 is used to detect the received The computer 35 is used to receive the image detected by the wavefront distortion detector 34, calculate the wavefront distortion information, and control the wavefront distortion correction device to store the image taken by the CCD camera 45; the tilt mirror 41 realizes partial wavefront phase compensation correction by changing the tilt angle; the deformable mirror 42 realizes partial wavefront phase compensation correction by changing the surface shape; the second filter 43 is used to filter the background stray light and extract the scattered return light of the target with a specific wavelength; the second converging lens 44 is used to focus the light beam to the CCD camera 45; the CCD camera 45 is used to image the corrected target.

[0108] Example 1

[0109] like Figure 1 As shown, this embodiment provides an adaptive optical system based on an excitation light beacon, comprising: a laser emitting device 1, a telescope 21, a collimating lens 22, a beam splitter 311, a first filter 32, a first converging lens 33, a Hartmann sensor, a computer 35, a tilt mirror 41, a continuous surface discrete drive deformable mirror, a second filter 43, a second converging lens 44, and a CCD camera 45;

[0110] The high-energy laser generated by the laser emitting device 1 is focused on the target surface through the focusing component in the laser emitting device 1, so that the temperature of the target surface is increased or ablated, and a spectrum is excited; wherein the radiation spectrum generated by the high-energy laser irradiating the target includes a thermal radiation spectrum, a Raman spectrum and a plasma spectrum; the spectrum includes target excitation light and target image information. The target excitation light and the target image information are received and converged by the telescope 21, and converted into parallel beams by the collimating lens 22. The received return light is then refracted by the tilt mirror 41 and the deformable mirror 42 in turn and irradiated to the beam splitter 311. The spectroscope 311 divides the light into reflected light and transmitted light; after the reflected light generated by the spectroscope 311 passes through the first filter 32 to extract the excitation light signal of a specific wavelength, the position of the first converging lens 33 is adjusted so that the focused light spot is completely received by the wavefront distortion detector 34; the wavefront distortion detector 34 transmits the collected image information to the computer 35; at the same time, the transmitted light generated by the spectroscope 311 passes through the second filter 43 and the second converging lens 44 in sequence, and is imaged on the CCD camera 45 and transmitted to the computer 35; the computer 35 obtains the wavefront distortion information by solving the calculation, and converts it into a driver control signal after processing, and then transmits it to the tilt mirror 41 and the deformable mirror 42 respectively to generate a conjugate distorted wavefront phase, which is offset by the wavefront distortion phase, thereby realizing adaptive optical correction; then, the received return light passes through the spectroscope 311, and then continues to repeat for the next adjustment until the adaptive optical system completes the correction of the imaging clarity.

[0111] Wherein, when the deformable mirror 42 is a continuous surface discretely driven deformable mirror, if the driving processes between each driver are independent of each other, the influence of the surface shape of the entire deformable mirror 42 on the wavefront phase distribution of the light field is regarded as a linear combination of the influence of each driver on the light field:

[0112] in, L ——the total number of actuators on the deformable mirror,

[0113] v j ——No. j The voltage applied to the driver,

[0114] D j ( x , y )——In the j The influence function of each driver.

[0115] In a high-power solid-state laser device, the influence function of the actuator on the continuous surface discrete drive deformable mirror is a Gaussian function or a super-Gaussian function, expressed as:

[0116]

[0117] in, a ——driver cross-link value,

[0118] d - the distance between the actuators,

[0119] α ——Gaussian function order.

[0120] Example 2

[0121] like Figure 2 As shown, this embodiment provides an adaptive optical system based on an excitation light beacon, comprising: a laser emitting device 1, a telescope 21, a collimating lens 22, a dichroic mirror 312, a first filter 32, a first converging lens 33, a Hartmann sensor, a computer 35, a tilting mirror 41, and a continuous surface discrete drive deformable mirror;

[0122] The high-energy laser generated by the laser emitting device 1 passes through the dichroic mirror 312, and then is deflected by the deformable mirror 42 and the tilt mirror 41 in sequence, and then passes through the collimating lens 22 first, and then is emitted toward the target direction by the telescope 21, wherein the telescope 21 focuses the laser at the target by adjusting the focal length, so that the surface temperature of the target is increased or ablated, and a spectrum is excited; wherein the radiation spectrum generated by the high-energy laser irradiating the target includes a thermal radiation spectrum, a Raman spectrum, and a plasma spectrum. The excitation light generated by the target is then received and converged by the telescope 21, and converted into a parallel beam through the collimating lens 22. The received return light is then deflected by the tilt mirror 41 and the deformable mirror 42 in sequence and then irradiated to the dichroic mirror 312. The dichroic mirror 312 reflects the received return light, and after the return light signal of a specific wavelength is extracted by the first filter 32, the position of the first converging lens 33 is adjusted so that the converged light spot is completely received by the wavefront distortion detector 34. The wavefront distortion detector 34 transmits the image information in the collected return light to the computer 35, and the computer 35 obtains the wavefront distortion information through calculation, and after processing, it is converted into a driver control signal and transmitted to the tilt mirror 41 and the deformable mirror 42 respectively to generate a conjugate distorted wavefront phase, which offsets the wavefront distortion phase, thereby realizing adaptive optical correction. Subsequently, the target image information scattered return light after wavefront correction passes through the dichroic mirror 312, and then passes through the first filter 32 and the first converging lens 33 in sequence, and continues to repeat for the next adjustment until the adaptive optical system completes the correction of imaging clarity.

[0123] The laser generated by the laser emitting device 1 is loaded with a conjugate distorted wavefront phase factor after passing through the tilt mirror 41 and the deformable mirror 42, and the wavefront distortion generated by the atmosphere is offset during atmospheric transmission, thereby realizing adaptive optical correction. The corrected laser has a smaller focused spot at the target, and the spot power density is increased, thereby improving the ablation effect on the target.

[0124] In summary, the present invention provides an adaptive optical system based on an excitation light beacon, which uses the excitation light generated by laser heating or ablation on the target surface as the beacon of the adaptive optical system, which is received by the telescope device after being transmitted through the atmosphere and detected by the wavefront distortion detection device, and the wavefront information is solved by the computer to control the wavefront distortion correction device to load the distorted wavefront conjugate phase to achieve the correction of the aberration, which can achieve clear imaging of the target or improve the power density of the laser focus point. The beacon light of this system is generated at the target, which is suitable for target detection at various heights, and there is no problem of focusing anisotropy; in addition, the correction capability of this system has no requirements on the roughness of the target surface, and at the same time has the advantages of high closed-loop bandwidth of the adaptive optical technology based on wavefront detection.

[0125] The above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. An adaptive optical system based on an excitation light beacon, characterized in that: include: A receiving unit, used for receiving the target excitation light and converting the focused light into parallel light; A wavefront phase compensation correction unit, used for receiving the parallel light; A beam splitter, used for receiving the light beam output by the wavefront phase compensation correction unit and splitting the light beam into two beams; A wavefront distortion detection unit, used for receiving the first light beam output by the beam splitter and detecting the wavefront distortion information of the first light beam; An imaging detection unit, used for receiving the second light beam output by the beam splitter and imaging the target; A terminal is used to receive the wavefront distortion information calculated by the wavefront distortion detection unit and the image output by the imaging detection unit, and after processing, output control information to control the wavefront phase compensation correction unit to perform wavefront correction on the received light; Among them, the excitation light generated by laser heating or ablation on the target surface is used as a beacon of the adaptive optical system.

2. The adaptive optical system based on the excitation light beacon according to claim 1, characterized in that: The wavefront distortion detection unit comprises: a first converging lens, receiving the first light beam output by the beam splitter, and focusing the first light beam onto a wavefront distortion detector; The wavefront distortion detector detects the wavefront distortion information of the received first light beam.

3. The adaptive optical system based on the excitation light beacon according to claim 2, characterized in that: The imaging detection unit comprises: A second converging lens receives the second light beam output by the beam splitter and focuses the light beam onto the CCD camera; The CCD camera images the calibrated target; the image taken by the CCD camera is stored by the terminal.

4. The adaptive optical system based on the excitation light beacon according to claim 1, characterized in that: The wavefront phase compensation correction unit comprises: A first wavefront phase compensation correction device, used for receiving the parallel light, and receiving control information output by the terminal to control the optical path of the first wavefront phase compensation correction device to compensate and correct a part of the wavefront phase; The second wavefront phase compensation correction device is used to receive the light beam output by the first wavefront phase compensation correction device, and simultaneously receive the control information output by the terminal to control the optical path of the second wavefront phase compensation correction device to perform partial wavefront phase compensation correction.

5. The adaptive optical system based on the excitation light beacon according to claim 4, characterized in that: The first wavefront phase compensation correction device includes a tilt mirror, and the tilt mirror receives control information output by the terminal to control the tilt angle of the tilt mirror; The second wavefront phase compensation correction device includes a deformable mirror, and the deformable mirror receives control information output by the terminal to control the surface shape of the deformable mirror.

6. The adaptive optical system based on excitation light beacon according to claim 3, characterized in that: The wavefront distortion detection unit further includes a first filter; the reflected light generated by the beam splitter first passes through the first filter and then is converged by the first converging lens; The imaging detection unit further includes a second filter; the transmitted light generated by the beam splitter first passes through the second filter and is then converged by the second converging lens.

7. An adaptive optical system based on an excitation light beacon, characterized in that: include: The transmitting and receiving unit is used to transmit the laser to the target, and after receiving the excitation light of the target, convert the focused light into parallel light; A wavefront distortion correction unit, used for receiving the parallel light and for receiving the laser light transmitted by the dichroic mirror; a dichroic mirror, used for reflecting the light beam output by the wavefront distortion correction unit and transmitting the laser light generated by the laser emitting device; A wavefront distortion detection unit, used for receiving the light beam reflected by the dichroic mirror and detecting the wavefront distortion information of the reflected light beam; A terminal is used to receive the wavefront distortion information calculated by the wavefront distortion detection unit, and after processing, output control information to control the wavefront distortion correction unit to perform wavefront correction on the received light; Among them, the excitation light generated by laser heating or ablation on the target surface is used as a beacon of the adaptive optical system.

8. The adaptive optical system based on excitation light beacon according to claim 7, characterized in that: The wavefront distortion detection unit comprises: a first converging lens, receiving the light beam reflected by the dichroic mirror, and focusing the reflected light beam onto the wavefront distortion detector; The wavefront distortion detector detects the wavefront distortion information of the received reflected light beam.

9. The adaptive optical system based on excitation light beacon according to claim 7, characterized in that: The wavefront distortion correction unit comprises: A first wavefront phase compensation correction device, used for receiving the parallel light, and receiving control information output by the terminal to control the optical path of the first wavefront phase compensation correction device to compensate and correct a part of the wavefront phase; A second wavefront phase compensation correction device, used for receiving the light beam output by the first wavefront phase compensation correction device, and receiving control information output by the terminal to control the optical path of the second wavefront phase compensation correction device to perform partial wavefront phase compensation correction; The first wavefront phase compensation correction device includes a tilt mirror, and the tilt mirror receives control information output by the terminal to control the tilt angle of the tilt mirror; The second wavefront phase compensation correction device includes a deformable mirror, and the deformable mirror receives control information output by the terminal to control the surface shape of the deformable mirror.

10. The adaptive optical system based on excitation light beacon according to claim 8, characterized in that: The wavefront distortion detection unit also includes a first filter; the light beam reflected by the dichroic mirror first passes through the first filter and then is converged by the first converging lens.

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