CN111967174A - Laser dynamics solving method and system based on light grid - Google Patents

Abstract

The invention discloses a laser dynamics solution method and system based on a ray grid, and relates to the field of optical finite element analysis. The method includes: meshing the target object according to a finite element analysis algorithm, establishing a tetrahedral mesh list, and recording the sequence information of each volume unit; The information determines the data for the ray segments within each ray grid; the laser dynamics problem is solved based on the data for the ray segments within each ray grid. The invention unifies the laser propagation process in the light grid, saves the tedious process of repeatedly replacing the grid, makes it possible to use the tetrahedral grid to solve the laser dynamics problem, and uses the tetrahedral grid to study the laser dynamics process. , the entire research object is no longer limited to objects of regular shape, but can also completely describe the physical process of light on the surface of the medium.

Description

Laser Dynamics Solution Method and System Based on Ray Grid

technical field

The invention relates to the field of optical finite element analysis, in particular to a method and system for solving laser dynamics based on a ray grid.

Background technique

At present, due to the limitation of computational power and geometric algorithms, traditional laser dynamic process algorithms for media are usually based on hexahedral meshes, and even many can only be based on cubic meshes. As shown in Figure 6, taking the laser medium in the shape of a slat as an example, the traditional method is to divide the slat into a grid along the three directions of length, width and height, and the grid size is dx*dy*dz. Then calculate the light field transmission, and divide the field coordinates (x, y, z) by the grid size to obtain the array number of the grid in the x, y, z directions: i=x/dx, j=y/dy, k =z/dz. Thus, the information of the gain unit at the (x, y, z) point is obtained.

The application scenario of the traditional method is relatively simple. This hexahedral mesh can only be used for bulk solid media. Once it is used for other configuration media, such as cylinders, it cannot describe the surface features of objects. Because, the existing methods can only approximate the circular configuration as a stepped shape, and cannot perfectly describe the surface features of these objects. Moreover, as the granularity decreases, the demand for memory also increases sharply, resulting in poor practical application effect. In addition, for cylindrical objects, it can also be approximated by reducing the particle size. For objects with vertex angles, especially acute angles, this method cannot be used to solve the laser dynamics process at all.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide a method and system for solving laser dynamics based on a ray grid, aiming at the deficiencies of the prior art.

The technical scheme that the present invention solves the above-mentioned technical problems is as follows:

A method for solving laser dynamics based on ray grid, including:

Mesh the target object according to the finite element analysis algorithm, establish a tetrahedral mesh list, and record the order information of each volume element;

Determine a ray grid according to the trajectory of the light passing through the target object, and determine the data of each ray line segment in the ray grid according to the sequence information;

The laser dynamics problem is solved based on the data of the ray segments within each said ray grid.

Another technical scheme that the present invention solves the above-mentioned technical problem is as follows:

A ray grid-based laser dynamics solution system, including:

The first grid establishment unit is used for meshing the target object according to the finite element analysis algorithm, establishing a tetrahedral grid list, and recording the sequence information of each volume unit;

a second grid establishing unit, configured to determine a ray grid according to the trajectory of the light passing through the target, and determine the data of each ray line segment in the ray grid according to the sequence information;

The computing unit is used for solving the laser dynamics problem according to the data of the ray segment in each of the ray grids.

The beneficial effects of the present invention are: the present invention introduces the tetrahedral grid to describe the gain calculation problem of the special-shaped medium, and then creates a ray grid to record the data of the ray tracing, expands the calculation application scene of the optical amplification process, and solves the problem of solving the problem. The existing solution method can only be used for the problem of cubic configuration medium, and the laser propagation process is unified in the ray grid, which saves the tedious process of repeatedly replacing the grid, and makes it possible to use tetrahedral grid to solve the laser dynamics problem. , and because the tetrahedral mesh is used to study the laser dynamics process, the entire research object is no longer limited to objects with regular shapes, and the physical process of light on the surface of the medium can also be completely described. Even for curved surfaces, the optical process of the entire surface can be more perfectly simulated by the computer because the uneven mesh can adjust the particle size to meet the surface of different curvatures.

Advantages of additional aspects of the invention will be set forth, in part, from the following description, and in part will become apparent from the following description, or may be learned by practice of the invention.

Description of drawings

1 is a schematic flowchart of an embodiment of a laser dynamics solution method of the present invention;

2 is a schematic diagram of a ray grid structure provided by other embodiments of the laser dynamics solution method of the present invention;

3 is a schematic diagram of a red-black tree structure provided by other embodiments of the laser dynamics solution method of the present invention;

4 is a schematic diagram of tetrahedral grid numbering provided by other embodiments of the laser dynamics solution method of the present invention;

5 is a schematic diagram of a structural framework provided by an embodiment of the laser dynamics solving system of the present invention;

FIG. 6 is a schematic diagram of the geometric configuration of the traditional hexahedral mesh segmentation.

Detailed ways

The principles and features of the present invention will be described below with reference to the accompanying drawings. The embodiments are only used to explain the present invention, but not to limit the scope of the present invention.

It should be noted that the tetrahedral finite element algorithm has long been used in engineering mechanics, thermal and other fields to solve the field function problem on the finite element element. As shown in Figure 6, an exemplary traditional hexahedral mesh is provided. Schematic diagram of the segmented geometry. But the entire laser dynamics process includes not only the interaction between light and medium (the local field function solution), but also the beam propagation and amplification process (transport problem). Moreover, in practice, the local field function and the transport problem interact with each other. In view of this special situation, this application proposes a ray grid based on the tetrahedral finite element algorithm, which is used to describe the transport problem of light transmission at the same time, which can describe the influence of light and grid at the same time, and solve the tetrahedron with minimum memory consumption. Mesh laser dynamics solution problem. The following describes with examples.

As shown in FIG. 1 , it is a schematic flowchart of an embodiment of the laser dynamics solution method of the present invention. The laser dynamics solution method is implemented based on a ray grid and is suitable for laser dynamics solution of irregular-shaped objects, including:

S1, mesh the target object according to the finite element analysis algorithm, establish a tetrahedral mesh list, and record the order information of each volume element;

S2, determining the ray grid according to the trajectory of the light passing through the target object, and determining the data of the ray line segments in each ray grid according to the sequence information;

S3, solve the laser dynamics problem according to the data of the ray segment in each ray grid.

It should be understood that the specific program used to perform the finite element analysis can be set according to actual needs.

For example, finite element analysis can be performed using software such as Femap+NX Nastran, COMSOL Multiphysics or pFEPG.

As shown in Figure 2, an exemplary schematic diagram of the tetrahedral finite element mesh structure is provided. The ray mesh is equivalent to that when the light is transmitted in the tetrahedral finite element mesh, it sequentially touches the surface of the tetrahedral mesh, and is represented by These surfaces divide the light into segments of unequal length. For ease of illustration, assuming that the target is a cubic crystal, the method shown in Figure 2 is used to tetrahedral the crystal. The dotted line is the light, and the arrow of the dotted line is the propagation direction of the light. The light passes through the crystal from the left side of the crystal, and the light In the process of passing through the entire tetrahedral grid, the ray first hits the surface triangle S0 of the grid c1, and then the ray r1 in the grid c1 travels a distance, hits the contact surface S1 between c1 and c2, and then enters the c2 net Then the ray r2 in the grid c2 travels a distance, hits the contact surface S2 of c2 and c3, and continues this process until it hits the last surface grid.

Taking mesh c1 as an example, the mesh itself is a volume element, and each surface triangle of mesh c1 is a surface element.

Ray tracing can be performed within the tetrahedral grid to obtain a ray grid formed by the intersection of the ray and the tetrahedral grid. It should be understood that the ray tracing can be implemented using existing software and systems, or original The program traces rays. For example, commercial software such as TracePro, ZEMAX, etc. can be used.

It should be understood that the data of the ray segment in each ray grid can be selected and set according to actual needs, for example, the length of the current ray segment, the grid to which the current ray segment belongs, the surface triangle from which the current ray segment exits, and the current ray segment can be recorded. The physical parameters such as light intensity, etc., are set according to the calculation requirements. For example, if the population inversion equation is to be solved, the recorded information may be the population inversion density.

At this time, the ray r is replaced by a sequence of ray segments rk (k=1, 2,...,K), where K is the number of ray segments.

Due to the existence of the ray grid, the entire laser dynamics solution problem can be realized on the ray grid. In the ray grid, the ray grid that affects the local field at point i must be the ray grid with cid equal to i. In addition, the ray propagation problem can also be solved directly on the ray grid. The local field solution on the finite element grid and the light amplification process on the ray can be solved on the ray grid.

Among them, i is the mesh number recorded when the tetrahedral finite element mesh is established, and cid is the ID of the tetrahedral mesh that intersects with the ray.

In this embodiment, the tetrahedral mesh is introduced to describe the gain calculation problem of the special-shaped medium, and then the ray mesh is created to record the data of the ray tracing, so as to expand the calculation application scene of the optical amplification process, and solve the problem that the existing solution method only It can be used for the problem of cubic configuration medium, and the laser propagation process is unified in the ray grid, eliminating the tedious process of repeatedly replacing the grid, making it possible to use the tetrahedral grid to solve the laser dynamics problem. The volume grid studies the laser dynamics process, and the entire research object is no longer limited to regular-shaped objects, and can also completely describe the physical process of light on the surface of the medium. Even for curved surfaces, the optical process of the entire surface can be more perfectly simulated by the computer because the uneven mesh can adjust the particle size to meet the surface of different curvatures.

Optionally, in some possible implementations, the target object is meshed according to a finite element analysis algorithm, a tetrahedral mesh list is established, and the order information of each volume element is recorded, specifically including:

Mesh the target object according to the finite element analysis algorithm, establish a tetrahedral mesh list, and record the ID of each volume element and the ID of each surface element.

Specifically, vec_cell and vec_triangle can be established, vec_cell records the sequential vertex coordinates of the tetrahedron, which is equivalent to recording the vertex numbers of its four surface triangles, and vec_triangle records the vertex numbers of the triangle.

It should be understood that vec_triangle only records different surface triangles, that is, surface triangles with common vertices are recorded only once to prevent repeated recording.

After the vec_cell and vec_triangle are recorded, the ID of the tetrahedron can be determined according to the sequential vertex coordinates of the tetrahedron, and the ID of the surface triangle can be determined according to the vertex number of the surface triangle. Specific examples are given below.

As shown in Figure 4, the four vertices of grid i are recorded as i1, i2, i3, i4 in order, then the surface triangles corresponding to the vertices are named S1, S2, S3, S4 respectively. Taking S1 as an example, the opposite The vertex is i1, and the three vertices that make up S1 are i2, i3, and i4, respectively. After recording all the surface triangles, the data obtained are shown in Table 1.

Table 1

Surface Triangle Number Surface triangles correspond to vertex order S1 i2,i4,i3 S2 i1,i3,i4 S3 i1,i4,i2 S4 i1,i2,i3

It should be understood that the vertex order can be recorded according to a preset rule, for example, can be recorded according to the left-hand rule, so that the left-hand rule can be used for the vertex order, so as to facilitate the normal vector direction of each surface triangle for subsequent calculation.

For example, according to the left-hand rule, following the directions of i2, i4 and i3, it can be concluded that the direction of the surface triangle S1 points to the vertex i1.

According to the above method to record all the grids, only 4N*8 bytes are needed, and N is the number of body units, which can reduce the repeated triangles recorded.

It should be noted that the flux can be obtained by ray tracing, and then the intersection of the ray and the finite element surface element can be determined based on this, so as to obtain the serial number of the surface element, but the serial number of the volume element where the ray is located cannot be obtained. , therefore, by recording the ID of each volume unit and the ID of each surface unit, the serial number of the volume unit where each segment of light is located can be easily determined.

Optionally, in some possible implementations, the target object is meshed according to a finite element analysis algorithm, a tetrahedral mesh list is established, and after the sequence information of each volume element is recorded, the method further includes:

Taking the ID of the surface unit as the key and the ID of the body unit as the value, a red-black tree is established according to the affiliation between the surface unit and the body unit. The red-black tree is used to find the ID of the body unit to which it belongs according to the ID of the surface unit.

It should be noted that the flux can be obtained by ray tracing, and then the intersection of the ray and the finite element surface element can be determined based on this, so as to obtain the serial number of the surface element, but the serial number of the volume element where the ray is located cannot be obtained. , and by introducing a red-black tree, this problem can be solved. A red-black tree is a self-balancing binary search tree, a data structure used in computer science, typically used to implement associative arrays.

For example, assuming that the greater than node key value is on the right and the lesser node key value is on the left, as shown in FIG. 3, an exemplary red-black tree structure is provided.

Taking the first node as an example, its key is S4 and its value is c1, indicating that the surface element with serial number S4 belongs to the volume element with serial number c1; taking the first node of the left subtree as an example, its key is S2 , the values are c2 and c3, indicating that the surface unit with sequence number S2 belongs to the body unit with sequence number c2 or belongs to the body unit with sequence number c3.

It should be noted that finding the number of the volume unit through the red-black tree not only successfully makes the ray grid method possible, but also reduces the memory consumption as a whole, and the algorithm complexity is reduced from O(N) to O(logN). Taking the calculation of tens of millions of grids as an example, the existing method and method take about 1 second to query once, but the method provided by the present invention can be completed in only a few microseconds, and the speed is increased by 100,000 times.

Because the operation of establishing a red-black tree in the present invention needs to occupy at most 3K*8+2S*8 bytes, when the number of grids is large, K≈N/2. Among them, K is the number of all non-repeating surface units, N is the number of body units, and S is the number of surface units that light passes through, generally S～N^(2/3).

Even with a high estimate, the entire operation of building a red-black tree consumes only 3N*8 bytes of memory. Combined with the memory consumption of the previous grid establishment, the entire solution consumes 7N*8 bytes of memory. It is also smaller than 9N*8 bytes of the original technical solution. Taking the tetrahedral mesh as an example, it is obvious that this solution can reduce the recording of repeated triangles. The repeated triangles are defined as the same vertex but different order, that is, two triangles with the opposite direction of the triangle normal vector obtained according to the right-hand rule, which saves memory. .

Optionally, in some possible implementation manners, the data of the ray segment in each ray grid is determined according to the sequence information, which specifically includes:

Trace the ray, and determine the ID of the surface unit that the ray passes through according to the trace result;

Taking the ID of the surface unit as the key, find the value corresponding to the key from the red-black tree, and determine the ID of the body unit through which the light passes according to the value corresponding to the key;

The physical parameters used to solve the laser dynamics problem within each ray mesh are determined based on the ID of the volume element that the ray passes through.

Specifically, tracing can be performed in the following manner.

Trace the light passing through the target, determine the flux of the light, solve the rate equation of the light according to the flux, and obtain the field function described by the flux, and determine the intersection of the light and the surface unit according to the field function. Determines the ID of the surface element that the light traverses.

For example, the field function can be a scalar field with inversion of the particle number. After the field function is determined, the AABB Tree algorithm can be used to quickly obtain the intersection of the light and the finite element surface element, so as to obtain the serial number of the surface element, that is, the ID of the surface element.

By determining the field function of the light, the serial number of the surface unit that the light passes through can be quickly obtained, which has the advantage of fast search speed.

Optionally, in some possible implementations, the laser dynamics problem is solved according to the following formula:

Among them, f() is the laser dynamics function, r(k) is the sequence of ray segments, k=1, 2,..., K, K is the number of ray segments in the target, and cid is each ray net The ID of the grid, i is the serial number of the volume unit, and u(i) is the variable in each volume unit recorded in the order of the volume unit number i.

It should be understood that f() can be any laser dynamic function, such as the number flip function, which is commonly used. Usually, this is an iterative solution process because the field function u(i) also affects the power of the light. A specific example is given below in combination with the above formula.

For example, in the laser amplification process, u(i) is often taken as the population inversion density n ₂ , and the relationship between the population inversion and the pump light intensity I _p and the signal light intensity _IL is shown in the following formula.

是介质在泵浦光波长的吸收截面，

是介质在泵浦光波长的发射截面，

是介质在信号波长的吸收截面，

是介质在信号波长的发射截面。τ_f是上能级寿命。h是普朗克常数，vP是泵浦光的频率，vL是信号光的频率。n_tot是离子掺杂浓度。在光线网格计算中，上式化简后写为：in,

is the absorption cross section of the medium at the pump wavelength,

is the emission cross section of the medium at the pump wavelength,

is the absorption cross section of the medium at the signal wavelength,

is the emission cross section of the medium at the signal wavelength. τ _f is the upper level lifetime. h is Planck's constant, vP is the frequency of the pump light, and vL is the frequency of the signal light. n _tot is the ion doping concentration. In the ray grid calculation, the above formula is simplified and written as:

是泵浦吸收系数。ΔP_L/ΔV＝gI_L是信号功率提取密度，

是饱和增益。where rk is the sequence of ray segments, ΔP _p /ΔV=αI _p is the pump power absorption density,

is the pump absorption coefficient. ΔP _L /ΔV= _gIL is the signal power extraction density,

is the saturation gain.

Due to the existence of the ray grid, the entire laser dynamics solution problem can be realized on the ray grid. In the ray grid, the ray grid that affects the local field at point i must be a ray grid with cid equal to i, so that the local field solution that originally needs to be solved on the finite element grid and the light amplification on the ray can be achieved. All processes can be solved uniformly on the ray grid.

It can be understood that in some embodiments, some or all of the above-mentioned embodiments may be included.

As shown in FIG. 5, it is a schematic diagram of the structural framework provided by the embodiment of the laser dynamics solution system of the present invention. The laser dynamics solution method is implemented based on a ray grid and is suitable for laser dynamics solution of irregular-shaped objects, including:

The first mesh establishment unit 1 is used for meshing the target object according to the finite element analysis algorithm, establishing a tetrahedral mesh list, and recording the sequence information of each volume element;

The second grid establishing unit 2 is used to determine the ray grid according to the trajectory of the light passing through the target, and determine the data of the ray line segments in each ray grid according to the sequence information;

The computing unit 3 is used to solve the laser dynamics problem according to the data of the ray segment in each ray grid.

In this embodiment, the tetrahedral mesh is introduced to describe the gain calculation problem of the special-shaped medium, and then the ray mesh is created to record the data of the ray tracing, so as to expand the calculation application scene of the optical amplification process, and solve the problem that the existing solution method only It can be used for the problem of cubic configuration medium, and the laser propagation process is unified in the ray grid, eliminating the tedious process of repeatedly replacing the grid, making it possible to use the tetrahedral grid to solve the laser dynamics problem. The volume grid studies the laser dynamics process, and the entire research object is no longer limited to regular-shaped objects, and can also completely describe the physical process of light on the surface of the medium. Even for curved surfaces, the optical process of the entire surface can be more perfectly simulated by the computer because the uneven mesh can adjust the particle size to meet the surface of different curvatures.

Optionally, in some possible implementations, the first mesh establishment unit 1 is specifically configured to mesh the target object according to the finite element analysis algorithm, establish a tetrahedral mesh list, and record the ID and ID of each surface element.

Optionally, in some possible implementations, it also includes:

The modeling unit is used to use the ID of the surface unit as the key and the ID of the body unit as the value to establish a red-black tree according to the affiliation between the surface unit and the body unit. The red-black tree is used to find the body to which it belongs according to the ID of the surface unit The ID of the unit.

Optionally, in some possible implementations, the second grid establishing unit 2 is specifically configured to trace the light, and determine the ID of the surface unit through which the light passes according to the tracing result; using the ID of the surface unit as a key, Find the value corresponding to the key from the red-black tree, and determine the ID of the volume unit that the light passes through according to the value corresponding to the key; determine the ID of the volume unit that the light passes through to solve the laser dynamics in each ray grid The physical parameters of the problem.

Optionally, in some possible implementations, the computing unit 3 is specifically configured to solve the laser dynamics problem according to the following formula:

Among them, f() is the laser dynamics function, r(k) is the sequence of ray segments, k=1, 2,..., K, K is the number of ray segments in the target, and cid is each ray net The ID of the grid, i is the serial number of the volume unit, and u(i) is the variable in each volume unit recorded in the order of the volume unit number i.

It can be understood that in some embodiments, some or all of the above-mentioned embodiments may be included.

It should be noted that the above embodiments are product embodiments corresponding to the previous method embodiments. For the description of the product embodiments, reference may be made to the corresponding descriptions in the above method embodiments, which will not be repeated here.

The reader should understand that in the description of this specification, reference to the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples", etc., is intended to incorporate the embodiment or example. A particular feature, structure, material, or characteristic described is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, those skilled in the art may combine and combine the different embodiments or examples described in this specification, as well as the features of the different embodiments or examples, without conflicting each other.

In the several embodiments provided in this application, it should be understood that the disclosed apparatus and method may be implemented in other manners. For example, the method embodiments described above are only illustrative. For example, the division of steps is only a logical function division. In actual implementation, there may be other divisions. For example, multiple steps may be combined or integrated into another A step, or some feature, can be ignored, or not performed.

The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of various equivalent modifications or modifications within the technical scope disclosed by the present invention. Replacement, these modifications or replacements should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims (10)

1. A laser dynamics solving method based on ray grids is characterized by comprising the following steps:

mesh subdivision is carried out on the target object according to a finite element analysis algorithm, a tetrahedral mesh list is established, and sequence information of each body unit is recorded;

determining light ray grids according to the track of the light rays passing through the target object, and determining data of light ray segments in each light ray grid according to the sequence information;

and solving the laser dynamics problem according to the data of the ray segments in each ray grid.

2. The method of claim 1, wherein the mesh generation is performed on the target object according to a finite element analysis algorithm, a tetrahedral mesh list is established, and the sequence information of each body unit is recorded, and the method specifically comprises:

and meshing the target object according to a finite element analysis algorithm, establishing a tetrahedral mesh list, and recording the ID of each body unit and the ID of each surface unit.

3. The method of claim 2, wherein the mesh generation is performed on the target object according to a finite element analysis algorithm, a tetrahedral mesh list is established, and after the sequence information of each body unit is recorded, the method further comprises:

and establishing a red-black tree according to the subordination relation between the surface unit and the body unit by taking the ID of the surface unit as a key and the ID of the body unit as a value, wherein the red-black tree is used for searching the ID of the body unit according to the ID of the surface unit.

4. The method of claim 3, wherein determining data for ray segments within each ray grid based on the sequence information comprises:

tracking the light rays, and determining the ID of the surface unit through which the light rays pass according to a tracking result;

taking the ID of the surface unit as a key, searching a value corresponding to the key from the red and black tree, and determining the ID of the body unit through which the light ray passes according to the value corresponding to the key;

and determining physical parameters used for solving the laser dynamics problem in each ray grid according to the ID of the body unit through which the ray passes.

5. The ray mesh-based laser dynamics solving method according to any one of claims 1 to 4, wherein the laser dynamics problem is solved according to the following formula:

wherein f () is a laser dynamics function, r (K) is a sequence of ray segments, K is 1,2,. …, K is the number of ray segments in the target object, cid is the ID of each ray grid, i is the serial number of the body unit, and u (i) is a variable in each body unit recorded in the order of the body unit serial number i.

6. A ray mesh-based laser dynamics solving system, comprising:

the first mesh establishing unit is used for mesh generation of the target object according to a finite element analysis algorithm, establishing a tetrahedral mesh list and recording sequence information of each body unit;

the second grid establishing unit is used for determining light grids according to the track of the light passing through the target object and determining the data of light line segments in each light grid according to the sequence information;

and the computing unit is used for solving the laser dynamics problem according to the data of the ray segments in each ray grid.

7. The system of claim 6, wherein the first mesh creation unit is specifically configured to mesh the object according to a finite element analysis algorithm, create a list of tetrahedral meshes, and record the ID of each volume element and the ID of each surface element.

8. The ray mesh-based laser dynamics solving system of claim 7, further comprising:

and the modeling unit is used for establishing a red-black tree according to the subordination relation between the surface unit and the body unit by taking the ID of the surface unit as a key and the ID of the body unit as a value, and the red-black tree is used for searching the ID of the body unit according to the ID of the surface unit.

9. The system according to claim 8, wherein the second grid creating unit is specifically configured to trace the light ray, and determine the ID of the surface unit through which the light ray passes according to the trace result; taking the ID of the surface unit as a key, searching a value corresponding to the key from the red and black tree, and determining the ID of the body unit through which the light ray passes according to the value corresponding to the key; and determining physical parameters used for solving the laser dynamics problem in each ray grid according to the ID of the body unit through which the ray passes.

10. The system according to any of the claims 6 to 9, wherein the computing unit is specifically configured to solve the laser dynamics problem according to the following formula:

wherein f () is a laser dynamics function, r (K) is a sequence of ray segments, K is 1,2,. …, K is the number of ray segments in the target object, cid is the ID of each ray grid, i is the serial number of the body unit, and u (i) is a variable in each body unit recorded in the order of the body unit serial number i.

Images