Non-coated laser reflector array layout method

Abstract

The invention discloses a non-coated laser reflector array layout method, which relates to a laser ranging technology and comprises the following steps: determining a light spot form of a non-coated laser reflector with deviation; establishing a coordinate system under a laser reflector according to the determined light spot form, and configuring a rotation direction according to the established coordinate system; and determining an initial mounting angle of a first laser reflector of the laser reflector array, and according to the number of the laser reflectors, sequentially mounting and arranging the latter laser reflectors according to the angle interval of 90 degrees / n. According to the embodiment of the invention, a 90-degree / n non-coated laser reflector polarization array arrangement mode is designed, the problem of light spot annular energy homogenization of the non-coated laser reflector is solved, the reflection efficiency of the laser reflector can be improved, and stable tracking and precise positioning of a space target are realized.

Description

Technical Field

[0001] The present application relates to the field of laser ranging technology, and in particular to a method for arranging a non-coated laser reflector array. Background Art

[0002] A laser reflector is a special type of retroreflector. It consists of three mutually perpendicular reflective surfaces and an incident (or exit) surface. It is a tetrahedral pyramidal prism with spatially directional emission characteristics. Ideally, a laser beam incident from the bottom surface of the corner cube prism is reflected by the three right-angled surfaces, and the outgoing light is emitted in a direction parallel to the incident light.

[0003] In the field of aerospace, laser reflectors are essential components for tracking and measuring various types of aircraft. They are passive optical devices mounted on the surface of aircraft. Their function is to reflect the ranging laser beam along the original optical path in the incident direction to achieve precise measurement between the ranging point and the aircraft.

[0004] As a traditional laser reflector, its working technical status (divergence angle, maximum tilt angle, effective emission area, emissivity, far-field diffraction spot, velocity aberration compensation, etc.) is determined by the characteristics of the reflector (shape, size, angular error). For example, the angular error of the right-angle surface coating directly determines the far-field diffraction spot shape of the laser reflector and the degree of separation of the six sub-spots. Theory and experiments have proved that: when there is a deviation in the right angle of the corner reflector, the six sub-beams of the outgoing light are in a separated state, each with a small angle with the incident light. The energy distribution of the diffraction spot is also different from that of the ideal corner reflector. The far-field energy distribution of the ideal reflector without angular deviation is a central Airy disk, and the far-field energy distribution of the reflector with deviation is surrounded by six sub-ring lights in addition to the central Airy disk, such as Figure 1 shown.

[0005] In actual engineering applications, in order to increase the reflection area, the structure of the laser reflector is usually composed of a plurality of corner reflector array structures. Compared with a single corner reflector, it can significantly reduce the size and weight, improve the far-field angle of the laser reflector, and optically compensate for the distortion of the laser caused by atmospheric inhomogeneities during transmission. In order to achieve effective measurement of scientific goals, the laser reflector assembly should have a high laser reflectivity and a small divergence characteristic to ensure that the reflected signal has sufficient light intensity. For example, for low-orbit spacecraft, the laser reflector array usually adopts a hemispherical or semi-conical structure to ensure that ranging can be carried out even at low elevation angles; for high-orbit spacecraft, since a large reflection area is generally required, a flat circular arrangement is adopted.

[0006] Right-angle surface coating can greatly increase the observation range of the reflector. For low-orbit spacecraft, the internal total reflection angle is less than 17 degrees (for quartz glass), which cannot meet the observation range index requirements of the reflector, and thus the reflector must be coated. For medium and high-orbit spacecraft, reflectivity is the main problem that needs to be solved. Although coating can increase the effective angle of incidence, the three reflections will seriously reduce the reflectivity. At the same time, space radiation and alternating high and low temperatures will also affect the performance of the film layer. Therefore, non-coating methods have become the mainstream for medium and high-orbit spacecraft reflectors.

[0007] Without considering the reflector's polarization effect, the polarization state of the outgoing and incoming beams is identical, with no change in amplitude or phase. However, considering the reflector's polarization effect, only two of the six outgoing apertures have the same polarization state as the incoming beam, while the amplitude and phase of the remaining two orthogonal components of the outgoing light have changed relative to the original incident polarization. Actual distance measurement using lasers typically uses polarized light, and polarization must be considered when using uncoated right-angle surfaces. Summary of the Invention

[0008] The embodiment of the present application provides a method for arranging an array of non-coated laser reflectors, which solves the problem of energy homogenization of the light spot ring of the non-coated laser reflector, improves the reflection efficiency of the laser reflector, and realizes stable tracking and precise positioning of space targets.

[0009] An embodiment of the present application provides a method for arranging an array of uncoated laser reflectors, including: Determine the spot shape of an uncoated laser reflector with deviation; According to the determined light spot shape, a coordinate system under the laser reflector is established and a rotation direction is configured according to the established coordinate system; An initial installation angle of a first laser reflector of the laser reflector array is determined, and subsequent laser reflectors are sequentially installed and arranged at angular intervals of 90° / n based on the number of laser reflectors, wherein each laser reflector of the laser reflector array has a rotation axis so that the installation angle is controlled based on the rotation axis.

[0010] Optionally, determining an initial installation angle of a first laser reflector of the laser reflector array includes: The initial installation angle is determined according to the set angle with the X-axis of the coordinate system.

[0011] Optionally, depending on the number of laser reflectors, the subsequent laser reflectors are sequentially installed and arranged at 90° / n angle intervals, including: For the laser reflector array of the grid array, according to the initial installation angle, other laser reflectors are sequentially installed at an angle interval of 90° / n to form a grid array arrangement.

[0012] Optionally, for the petal-shaped planar array spatial reflector, according to the number of laser reflectors, the subsequent laser reflectors are sequentially installed and arranged at an angle interval of 90° / n, including: The angle between the lower edge of the first laser reflector of the laser reflector array and the X-axis is used as the initial installation angle; The other laser reflectors are sequentially installed at an angular interval of 90° / n to form a grid array arrangement.

[0013] Optionally, for spherical or hemispherical spatial laser reflectors, depending on the number of laser reflectors, the subsequent laser reflectors are sequentially installed and arranged at 90° / n angle intervals, including: The angle between the lower edge of the first laser reflector of each regional fan array and the X-axis is used as the initial installation angle; The other laser reflectors are sequentially installed at an angular interval of 90° / n to form a grid array arrangement.

[0014] The embodiment of the present application designs a 90° / n non-coated laser reflector polarization array arrangement to solve the problem of energy homogenization of the light spot ring band of the non-coated laser reflector. The method of the present application can improve the reflection efficiency of the laser reflector and achieve stable tracking and precise positioning of space targets.

[0015] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present application. The same reference symbols are used throughout the drawings to represent the same components. In the drawings: Figure 1 A schematic diagram of a light field spot pattern ring of a space laser reflector with deviation in the background technology; Figure 2 This is a schematic diagram of the basic process of the laser reflector array layout method according to an embodiment of the present application; Figure 3 Schematic diagram of the rotation angle coordinates of the optical laser reflector according to an embodiment of the present application; Figure 4 Schematic diagram of the rotation axis of the optical laser reflector according to an embodiment of the present application; Figure 5 This is a schematic diagram of a planar mounted array of optical laser reflectors according to an embodiment of the present application. DETAILED DESCRIPTION

[0017] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0018] Optical laser reflector arrays typically consist of multiple reflectors. Spatial arrangement can improve and enhance the uniformity of the separated diffraction beam rings, further compensating for and resolving the issues of scarce and unstable data in ranging blind areas caused by insufficient reflectors and excessive separation angles. A properly optimized spatial arrangement can further enhance laser reflection efficiency, improve detection probability and ranging accuracy, and improve detection uniformity, stability, and site observation efficiency. Reflector layout design employs various structural layout design methods to homogenize or enhance the light field intensity of the reflector diffraction spot rings, improving ranging performance and accuracy.

[0019] The embodiment of the present application provides a method for arranging a non-coated laser reflector array, such as Figure 2 As shown, the following steps are included: In step S101 , the spot shape of the non-coated laser reflector with deviation is determined.

[0020] In step S102, according to the determined spot shape, a coordinate system under the laser reflector is established and a rotation direction is configured according to the established coordinate system, for example, Figure 3 The coordinate system shown.

[0021] In step S103, an initial installation angle of the first laser reflector in the laser reflector array is determined. Based on the number of laser reflectors, subsequent laser reflectors are sequentially installed and arranged at 90° / n angular intervals. Each laser reflector in the laser reflector array has a rotation axis, and the installation angle is controlled based on the rotation axis. In this embodiment of the present application, all laser reflectors in the laser reflector array are installed by rotating the installation rotation axis by a certain angle.

[0022] In a specific example, Figure 4 As shown in the figure, the optical characteristics of the laser reflector are such that, by rotating the axis of rotation, the azimuth angles of the far-field spot pattern of a single non-coated laser reflector overlap at intervals of 90°, as shown in the attached figure. Figure 5 As shown, installing the reflector array at intervals of 90° / n (n is the number of laser reflectors) can homogenize the energy reflected by the array laser reflectors, making the light spot more uniform.

[0023] In some embodiments, determining the initial installation angle of the first laser reflector of the laser reflector array includes: determining the initial installation angle according to a set angle with the X-axis of the coordinate system, which can be any angle with the X-axis.

[0024] In some embodiments, according to the number of laser reflectors, the subsequent laser reflectors are sequentially installed and arranged at angular intervals of 90° / n, including: For the laser reflector array of the grid array, according to the initial installation angle, other laser reflectors are sequentially installed at an angle interval of 90° / n to form a grid array arrangement.

[0025] Take 9 reflectors as an example, Figure 5 In the actual arrangement, the initial installation angle of the first laser reflector in the array can be any angle that forms an angle with the X-axis; the installation angle of the second laser reflector is rotated 90° / n (n is the number of laser reflectors) around the installation rotation axis compared with the first laser reflector; the installation angle of the third laser reflector is rotated 90° / n (n is the number of laser reflectors) around the installation rotation axis compared with the second laser reflector; the installation angle of the fourth laser reflector is rotated 90° / n (n is the number of laser reflectors) around the installation rotation axis compared with the third laser reflector; and so on, the installation angle of the nth laser reflector is rotated 90° / n (n is the number of laser reflectors) around the installation rotation axis compared with the (n-1)th laser reflector, as shown in Table 1.

[0026] Schematic diagram of a conventional planar space reflector array. The initial installation angle of the first laser reflector in the array can be any angle between the lower edge of the reflector and the X-axis. The array structure is arranged 90° / n apart according to the installation azimuth of each laser reflector. Each reflector independently reflects polarized laser light, superimposing interference to homogenize the energy of the light spot ring, improving echo stability and reflection efficiency.

[0027] Table 1 In some embodiments, for a petal-shaped planar array spatial reflector, according to the number of laser reflectors, the subsequent laser reflectors are sequentially installed and arranged at an angle interval of 90° / n, including: The angle between the lower edge of the first laser reflector of the laser reflector array and the X-axis is used as the initial installation angle; The other laser reflectors are installed in sequence at an angle interval of 90° / n to form a grid array arrangement. Each reflector reflects its own polarized laser and interferes with it to homogenize the energy of the light spot ring, thereby improving the echo stability and reflection efficiency.

[0028] In some embodiments, for spherical or hemispherical spatial laser reflectors, according to the number of laser reflectors, the subsequent laser reflectors are sequentially installed and arranged at angular intervals of 90° / n, including: The angle between the lower edge of the first laser reflector of each regional fan array and the X-axis is used as the initial installation angle; The other laser reflectors are sequentially installed at an angular interval of 90° / n to form a grid array arrangement.

[0029] In a specific example, for the schematic diagram of the spherical / hemispherical space reflector array, the initial installation angle of the first laser reflector in each regional fan array can be any angle between the lower edge of the reflector and the X-axis; each regional fan array is arranged at an installation azimuth angle of 90° / n apart in the fan, and each reflector reflects its own polarized laser to superimpose interference, perform light spot ring energy homogenization, and improve echo stability and reflection efficiency.

[0030] Other different structures, such as fan-shaped, triangular, trapezoidal, circular and other special-shaped structures can also be designed for array according to the method of the present application.

[0031] The reflector structure of the present application can be a solid reflector or a hollow reflector; the material of the reflector can be various optical materials such as glass, engineering plastics, metal, etc.; considering the requirements of the space environment, the material of the solid right-angle prism when used in the space environment is fused quartz glass.

[0032] This application proposes a polarization state array method for space optical laser reflectors, which uses an azimuth angle arrangement of 90° / n intervals to homogenize the spot ring energy of the polarization state ranging laser far-field spot morphology, so as to improve the uniformity and stability of the ranging echo photons of the space non-coated laser reflector, and solve the problem of fluctuating data returned from the ranging station. The method of this application is conducive to improving the reflection efficiency and stability of the laser reflector, and realizing stable tracking and precise positioning of space targets.

[0033] It should be noted that, in the various embodiments of the present application, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0034] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of this application, ordinary technicians in this field can also make many forms without departing from the purpose of this application and the scope of protection of the claims, all of which are protected by this application.

Claims

1. A method for arranging an array of non-coated laser reflectors, characterized in that: include: Determine the spot shape of an uncoated laser reflector with deviation; According to the determined light spot shape, a coordinate system under the laser reflector is established and a rotation direction is configured according to the established coordinate system; An initial installation angle of a first laser reflector of the laser reflector array is determined, and subsequent laser reflectors are sequentially installed and arranged at angular intervals of 90° / n based on the number of laser reflectors, wherein each laser reflector of the laser reflector array has a rotation axis so that the installation angle is controlled based on the rotation axis.

2. The method for arranging an array of non-coated laser reflectors according to claim 1, wherein: Determining the initial mounting angle of the first laser reflector of the laser reflector array includes: The initial installation angle is determined according to the set angle with the X-axis of the coordinate system.

3. The method for arranging an array of non-coated laser reflectors according to claim 1, wherein: According to the number of laser reflectors, the subsequent laser reflectors are installed and arranged in sequence at 90° / n angle intervals, including: For the laser reflector array of the grid array, according to the initial installation angle, other laser reflectors are sequentially installed at an angle interval of 90° / n to form a grid array arrangement.

4. The method for arranging an array of non-coated laser reflectors according to claim 1, wherein: For the petal-shaped plane array space reflector, according to the number of laser reflectors, the subsequent laser reflectors are sequentially installed and arranged at an angle interval of 90° / n, including: The angle between the lower edge of the first laser reflector of the laser reflector array and the X-axis is used as the initial installation angle; The other laser reflectors are sequentially installed at an angular interval of 90° / n to form a grid array arrangement.

5. The method for arranging an array of non-coated laser reflectors according to claim 1, wherein: For spherical or hemispherical spatial laser reflectors, according to the number of laser reflectors, the subsequent laser reflectors are sequentially installed and arranged at 90° / n angle intervals, including: The angle between the lower edge of the first laser reflector of each regional sector array and the X-axis is used as the initial installation angle; The other laser reflectors are sequentially installed at an angular interval of 90° / n to form a grid array arrangement.

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