Laser optical system correction device and method for large-angle asymmetric aberration

Abstract

The invention relates to the technical field of laser optics, and discloses a laser optical system correction device and method for large-angle asymmetric aberration, and the device comprises an objective lens group which is used for receiving and converging a large-angle incident laser beam and other wave band beams different from the laser beam; the wedge-shaped spectroscope is used for separating the laser beam from the light beams of other wavebands; the wedge-shaped correction mirror is used for correcting optical axis inclination generated after the laser beams pass through the wedge-shaped spectroscope; and the convergent mirror group is used for carrying out aberration optimization on the laser beams corrected by the wedge-shaped correction mirror and converging the laser beams to a detector. The objective of the invention is to overcome the defects of contradiction between existing beam separation and optical axis inclination, insufficient asymmetric aberration correction capability, system structure redundancy and parameter mismatching.

Description

Technical Field

[0001] This invention relates to the field of laser optics technology, and discloses a laser optics system correction device and method for large-angle asymmetric aberrations. Background Technology

[0002] In laser optics applications, laser beams are often incident on optical systems at large angles and are easily accompanied by background stray light, auxiliary probe light, and other beams of other wavelengths. To avoid stray light interference, the laser beam must first be separated from other beams of other wavelengths. At the same time, large-angle incident light can cause significant asymmetric aberrations in the laser beam. If not corrected, this will cause beam spot distortion and uneven energy distribution, which will seriously affect the reception quality of subsequent detectors and the system performance.

[0003] The existing technology has the following core problems: 1. When traditional beam splitters perform band separation on large-angle incident beams, they are prone to introducing optical axis tilt deviation due to the refractive characteristics of the beam splitter, and this deviation cannot be eliminated by conventional lens groups. II. Existing correction devices are mostly designed for small-angle symmetrical aberrations and use simple lens combinations, which are difficult to adapt to the complex asymmetrical aberrations caused by large-angle incidence. The beam still has obvious distortion after correction. Third, although some devices integrate beam splitting and correction functions, the lack of coordination in the selection of optical components and spacing design leads to high optical path loss, poor aberration optimization effect, and difficulty in ensuring system stability. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing beam separation and optical axis tilt, insufficient asymmetric aberration correction capability, system structure redundancy and parameter mismatch, and to provide a laser optical system correction device and method for large-angle asymmetric aberrations.

[0005] To achieve the above-mentioned technical effects, the technical solution adopted by the present invention is as follows: A laser optical system correction device for large-angle asymmetric aberrations includes an objective lens group, a wedge beam splitter, a wedge corrector lens, and a converging lens group arranged sequentially along the optical path transmission direction. The objective lens group is used to receive and converge laser beams incident at large angles and other wavelength beams different from the laser beam; A wedge-shaped beam splitter is used to separate the laser beam from the other wavelength beams; A wedge-shaped corrector is used to correct the optical axis tilt of the laser beam after it passes through the wedge beam splitter. The converging lens group is used to optimize the aberrations of the laser beam after it has been corrected by the wedge-shaped corrector and converge it to the detector.

[0006] As a preferred embodiment, the objective lens group includes a first meniscus lens and a second meniscus lens arranged sequentially along the incident direction of the optical path.

[0007] As a preferred embodiment, the interval between the first meniscus lens and the second meniscus lens is 6.4 mm.

[0008] In a preferred embodiment, the wedge-shaped beam splitter is tilted, and the tilt angle between the wedge-shaped beam splitter and the horizontal plane is 45°.

[0009] In a preferred embodiment, the wedge-shaped corrective lens is tilted, and the tilt angle between the wedge-shaped corrective lens and the horizontal plane is 117°.

[0010] As a preferred embodiment, the converging lens group includes a third meniscus lens, a biconvex lens, a fourth meniscus lens, a fifth meniscus lens, a sixth meniscus lens, and a plano-concave lens arranged sequentially along the incident direction of the optical path.

[0011] In a preferred embodiment, the interval between the third meniscus lens and the biconvex lens is 2.5 mm; the interval between the biconvex lens and the fourth meniscus lens is 5 mm; the interval between the fourth meniscus lens and the fifth meniscus lens is 2.4 mm; the interval between the fifth meniscus lens and the sixth meniscus lens is 3.6 mm; and the interval between the sixth meniscus lens and the plano-concave lens is 1.1 mm.

[0012] This invention also proposes a method for correcting large-angle asymmetric aberrations in laser optical systems, comprising: S1: Receive and converge large-angle incident laser beams and other wavelength beams different from the laser beam using the objective lens group; S2: The converged beam is passed through a wedge-shaped beam splitter to separate the laser beam from the other wavelength beams; S3: Pass the separated laser beam through a wedge-shaped correction mirror to correct the optical axis tilt caused by the wedge-shaped beam splitter; S4: The laser beam after optical axis correction is optimized by using a converging lens group and then converged to the detector.

[0013] Compared with the prior art, the beneficial effects of this invention are: I. High accuracy of optical axis correction: Through the synergistic design of a 45° wedge beam splitter and a 117° wedge correction lens, the optical axis tilt deviation caused by large-angle incident light can be completely offset. After correction, the optical axis deviation is ≤0.05°, which is far superior to existing devices (the deviation is usually ≥0.5°). II. Thorough correction of asymmetric aberrations: The converging lens group adopts a combination structure of multiple meniscus lenses + biconvex lenses + plano-concave lenses. Combined with optimized lens spacing, it can eliminate asymmetric aberrations such as coma and astigmatism of large-angle incident lasers in all dimensions. After correction, the wavefront distortion of the beam is ≤λ / 20, where λ is the laser wavelength. 3. High system integration: The receiving-separation-correction-convergence functions are integrated into a single optical path, which is compact and avoids the errors caused by splicing multiple devices; IV. Strong stability and applicability: The parameters of each optical element (interval, tilt angle) have been optimized through simulation to adapt to large-angle incident light within a range of ±30°, and it is made of conventional optical glass, which is low in cost and has strong environmental adaptability. V. Significantly Improved Detection Quality: After processing by this device and method, the laser beam focused on the detector has a spot distortion rate of ≤2% and an energy concentration of ≥95%, which can effectively improve the detection accuracy and distance of the laser detection system. Attached Figure Description

[0014] Figure 1 This is a module structure diagram of the laser optical system correction device for large-angle asymmetric aberrations according to the present invention; Figure 2 This is a logic block diagram of the laser optical system correction method for large-angle asymmetric aberrations according to the present invention.

[0015] 1. Objective lens group; 11. First meniscus lens; 12. Second meniscus lens; 2. Wedge beam splitter; 3. Wedge corrector lens; 4. Converging lens group; 41. Third meniscus lens; 42. Biconvex lens; 43. Fourth meniscus lens; 44. Fifth meniscus lens; 45. Sixth meniscus lens; 46. Plano-concave lens; 5. Detector. Detailed Implementation

[0016] The present invention will now be described in further detail with reference to the embodiments and accompanying drawings. However, this should not be construed as limiting the scope of the above-described subject matter of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0017] like Figure 1 As shown in Example 1, a laser optical system correction device for large-angle asymmetric aberrations includes: I. Objective Lens Group 1 Function: Receives and converges laser beams incident at large angles, such as 1064nm infrared lasers and other wavelength beams, such as visible light background stray light, to reduce the divergence loss of the incident beam. Structure: A first meniscus lens 11 and a second meniscus lens 12 are arranged sequentially along the incident direction of the light path. The meniscus lens can effectively suppress field curvature aberration and is suitable for large-angle incident. Key parameters: The distance between the first meniscus lens 11 and the second meniscus lens 12 is fixed at 6.4 mm. This distance is optimized by optical simulation to minimize the propagation loss of the light beam between the lenses and ensure the converging effect.

[0018] II. Wedge-shaped beam splitter 2 Function: Based on the band-selective transmission or reflection characteristics, the laser beam converged by objective lens group 1 is separated from other band beams, such as the laser beam being transmitted and other band beams being reflected to the stray light absorption device. Installation method: tilted setting, with an angle of 45° to the horizontal plane; this angle design allows other wavelength beams to be reflected in a 90° direction, avoiding overlap with the laser beam path, while ensuring that the laser beam is transmitted to subsequent components along the original beam path direction (deviation ≤ 0.1°).

[0019] III. Wedge-shaped corrective lenses 3 Function: Precisely counteracts the optical axis tilt deviation of the laser beam after passing through the wedge beam splitter 2, restoring the laser beam to the ideal optical path direction; Installation method: tilted setting, with an angle of 117° relative to the horizontal plane; this angle is calculated using the optical refraction formula (combined with the wedge angle of the wedge beam splitter 2 and the laser wavelength), which can completely compensate for the optical axis tilt, and the optical axis deviation after correction is ≤0.05°.

[0020] IV. Converging Lens Group 4 Function: To optimize the asymmetric aberrations (coma, astigmatism) of the laser beam after optical axis correction, and to focus the beam onto detector 5, such as CCD or photodiode; Structure: Along the incident direction of the light path, a third meniscus lens 41, a biconvex lens 42, a fourth meniscus lens 43, a fifth meniscus lens 44, a sixth meniscus lens 45, and a plano-concave lens 46 are arranged sequentially; the lenses work together: the meniscus lens is responsible for correcting field curvature and astigmatism, the biconvex lens 42 enhances the converging ability, and the plano-concave lens 46 suppresses spherical aberration, forming a full-dimensional optimization of asymmetric aberrations; Key parameters: The spacing between each lens has been optimized through simulation, specifically: The distance between the third meniscus lens 41 and the biconvex lens 42 is 2.5 mm. The distance between the biconvex lens 42 and the fourth meniscus lens 43 is 5mm. The distance between the fourth meniscus lens 43 and the fifth meniscus lens 44 is 2.4 mm; The distance between the fifth crescent lens 44 and the sixth crescent lens 45 is 3.6 mm; The distance between the sixth crescent lens 45 and the plano-concave lens 46 is 1.1 mm.

[0021] like Figure 1As shown in Example 2, the present invention also provides a method for correcting laser optical systems with large-angle asymmetric aberrations, comprising the following steps: S1: Receive and converge a large-angle incident laser beam and other wavelength beams different from the laser beam using objective lens group 1; S2: The converged beam is passed through a wedge-shaped beam splitter 2 to separate the laser beam from the other wavelength beams; S3: Pass the separated laser beam through a wedge-shaped correction mirror 3 to correct the optical axis tilt caused by the wedge-shaped beam splitter 2; S4: The laser beam after optical axis correction is optimized by using the converging mirror group 4 and then converged to the detector 5.

[0022] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A laser optical system correction device for large-angle asymmetric aberrations, characterized in that, It includes an objective lens group (1), a wedge beam splitter (2), a wedge corrector (3), and a converging lens group (4) arranged sequentially along the optical path transmission direction; Objective lens group (1) is used to receive and converge laser beams incident at large angles and other wavelength beams different from the laser beam; A wedge-shaped beam splitter (2) is used to separate the laser beam from the other wavelength beams; A wedge-shaped correction mirror (3) is used to correct the optical axis tilt of the laser beam after passing through the wedge-shaped beam splitter (2); The converging lens group (4) is used to optimize the aberrations of the laser beam after it has been corrected by the wedge-shaped corrector (3) and converge it to the detector.

2. The laser optical system correction device for large-angle asymmetric aberrations according to claim 1, characterized in that, The objective lens group (1) includes a first meniscus lens (11) and a second meniscus lens (12) arranged sequentially along the incident direction of the light path.

3. The laser optical system correction device for large-angle asymmetric aberrations according to claim 2, characterized in that, The distance between the first meniscus lens (11) and the second meniscus lens (12) is 6.4 mm.

4. The laser optical system correction device for large-angle asymmetric aberrations according to claim 3, characterized in that, The wedge beam splitter (2) is tilted, and the tilt angle between the wedge beam splitter (2) and the horizontal plane is 45°.

5. The laser optical system correction device for large-angle asymmetric aberrations according to claim 4, characterized in that, The wedge-shaped corrective mirror (3) is tilted, and the tilt angle between the wedge-shaped corrective mirror (3) and the horizontal plane is 117°.

6. The laser optical system correction device for large-angle asymmetric aberrations according to claim 5, characterized in that, The converging lens group (4) includes a third meniscus lens (41), a biconvex lens (42), a fourth meniscus lens (43), a fifth meniscus lens (44), a sixth meniscus lens (45), and a plano-concave lens (46) arranged sequentially along the incident direction of the light path.

7. The laser optical system correction device for large-angle asymmetric aberrations according to claim 6, characterized in that, The interval between the third meniscus lens (41) and the biconvex lens (42) is 2.5 mm; the interval between the biconvex lens (42) and the fourth meniscus lens (43) is 5 mm; the interval between the fourth meniscus lens (43) and the fifth meniscus lens (44) is 2.4 mm; the interval between the fifth meniscus lens (44) and the sixth meniscus lens (45) is 3.6 mm; and the interval between the sixth meniscus lens (45) and the plano-concave lens (46) is 1.1 mm.

8. A method for correcting large-angle asymmetric aberrations in a laser optical system, characterized in that, include: S1: Use the objective lens group (1) to receive laser beams incident at large angles and other wavelength beams different from the laser beams, and converge them; S2: The converged beam is passed through a wedge-shaped beam splitter (2) to separate the laser beam from the other wavelength beams; S3: Pass the separated laser beam through a wedge-shaped correction mirror (3) to correct the optical axis tilt caused by the wedge-shaped beam splitter (2); S4: The laser beam after optical axis correction is optimized by using the converging mirror group (4) and then converged to the detector.

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