CN104808339A - Optical initial structure automatic generation method based on Delano figure - Google Patents

Abstract

The method of automatic generation of optical initial structure based on Delano diagram: the working steps are followed by ⑴. Optimal design of optical first-order quantity, based on Delano diagram, for y _i Coordinates, optimized with the design requirements as constraints, according to the optimized y _i Coordinates and y _i in Delano The relationship between the coordinates and other first-order quantities can be obtained for all first-order quantities of each team member in the system. ⑵. Automatic allocation of first-order parameters and optical materials in commercial optical optimization software, and establish a dynamic data link between the first step and optimization platform and commercial optical optimization software to realize the allocation of first-order parameters and optical materials. ⑶ The automatic optimization of image quality is realized in three steps. The invention solves the problem of solving the initial structure existing in the existing optical design. All execution steps are controlled by the program, but for different design requirements, the program calculates the constraints and objective functions in the optimization process by itself.

Description

Automatic Generation of Optical Initial Structure Based on Delano Diagram

technical field

The invention belongs to the field of optical imaging design, and in particular relates to an automatic generation method of an optical initial structure based on a Delano diagram.

Background technique

The current optical design often relies on the optimization design software Zemax, CODEV, OSLO, etc., which has achieved great convenience. But before using such optimization design software, a reasonable optical initial structure is needed as a starting point for optimization. The currently used method for solving the initial optical structure is the PWC method based on balanced primary aberrations. For a system composed of a small number of members, the PWC method can obtain some reasonable and usable structures. Such as Cassegrain system, Gregory system, RC system, Maksutov system, Schwardzschield system in two-mirror system, TMA system in three-mirror system, etc. The traditional PWC method is to solve five primary aberration sums and two chromatic aberration sums. But the traditional PWC method has the following three problems: (1) when using the PWC method, the optical designer needs to adjust the focal power of each team member The projection height y _i of the light rays passing through the edge of the entrance pupil emitted by the point on the axis on each team member, and the projection height of the light rays passing through the center of the entrance pupil emitted by the edge field of view on each team member to allocate. There is no universal and efficient way to assign these three variables to each group member. (2): The five aberration equations theoretically require five independent variables to find a unique solution. In optical design, a doublet has 2 independent PW parameters, a single lens has an independent P parameter or W parameter, and a mirror has no independent PW parameters (in the lens after confirming). In optical design, when the number of independent PWs of all used team members exceeds 5, the PW equation has no unique solution. In the actual design work, most of the slightly complicated system PW parameters are much larger than 5. For a complex photolithographic lens, such as lens #6084723 in the LENSVIEW lens library, use 28 team members to design. For a design effort of this magnitude, it is impossible to achieve a good design by solving five linear aberration equations. (3): The design idea of the PW method is to distribute the primary aberrations by changing the curvature distribution within each group member after the focal power distribution of the group members, and then to balance the primary aberrations. This kind of design thinking also has big problems for the design of more complex systems. It should be because for more complex systems, the optimization strategy we often use is to reserve some primary aberrations to balance advanced aberrations to obtain better image quality. Instead of completely balancing the primary aberrations to obtain the initial structure.

Due to the defects of the traditional design theory PWC method as mentioned above, there is no unified and efficient method for solving the initial structure of the optical imaging lens in the initial design stage.

Contents of the invention

In order to solve the problem of solving the initial structure existing in the existing optical design, the object of the present invention is to provide an automatic generation method of the optical initial structure based on the Delano diagram, so as to improve the efficiency of the optical design. The present invention should have following characteristics: according to design requirement, utilize Delano diagram, combine optimization algorithm to automatically generate the first-order quantity (optical power) of each group member of optics Edge ray height y _i , chief ray height The distance between each group member d _i ); according to the first-order quantity generated in the previous step, establish a dynamic data link (Zemax, CODEV, OSLO) through the first step optimization platform and commercial optical optimization design software, and assign each group in the optical optimization design software The material, focal power, and spacing of the members are used to obtain a rough structure; through dynamic data link control, the constraints of the design requirements are added to the optical optimization design software, and then the spacing and the working surfaces of each team member are re-optimized by optimizing the image quality. Curvature, to get a better initial structure.

The technical scheme for completing the above-mentioned invention task is as follows: a method for automatically generating an optical initial structure based on a Delano diagram, characterized in that the working steps are followed by (1) the optimization design of the first-order optical quantity, (2) the first-order quantity in the commercial optical optimization software And the automatic allocation of optical materials, ⑶. The automatic optimization of image quality is realized in three steps.

The optimal design of described step (1) optical first-order quantity is based on the Delano figure, for Coordinates, optimized with design requirements as constraints, according to the optimized Coordinates and in Delano The relationship between the coordinates and other first-order quantities can be obtained for all first-order quantities of each team member in the system. All first-order quantities depend on the Delano graph pair optimization is completed.

The distribution of the first-order quantities and materials in the step (2) in the commercial optical optimization software depends on the first-step optimization platform, and a dynamic data link is established between the first-step and optimization platform and the commercial optical optimization software to realize the first-order quantities Assignment of parameters and optical materials.

The automatic optimization of the described step (3) image quality also depends on the program platform where the first step optimization program is located, generates the basic constraints of the design in the commercial optimization software, then automatically writes the optimization design objective function, weight function, and then controls the process. Optimization of the spacing, curvature, etc. of each team member.

In other words, the contents and working methods of the above-mentioned components in the present invention can be described as follows:

The implementation of the present invention mainly completes through three steps. The first step is the optimal design of the optical first-order quantity. In the design of optical imaging lens, the first order optimization design should be carried out. For an optimal design, an objective function and a constraint function are required. The optimized objective function can be the deflection angle of light in each team member, or the total length of the system, or a mixture of the two, or other first-order quantities. The optimized constraint function mainly comes from the basic requirements of the design. For the design of a finite-distance optical system, the basic design requirements generally include NA, the total focal length of the system, the object-side field of view of the system, the image-side field of view, and the entrance pupil diameter of the system. For an infinite system, the basic design requirements generally include system focal length, object field of view, entrance pupil aperture, etc. According to the constraint function obtained from the design goal and the optimized objective function, through the iteration of the optimization algorithm, the incident height of the marginal light emitted by the on-axis point and the incident height of the chief light emitted by the off-axis point on each team member are continuously optimized, so that the optimized The objective function is minimized, thereby outputting a set of value.

meet the design goals of the value, according to the Delano diagram coordinates The relationship with other first-order quantities of each team member of the optical system is automatically obtained by the program. In order to quickly and efficiently generate optical initial structures, we need to establish a dynamic data link between the external optimization program platform and commercial optical optimization design software. optimized in the first step After the value and its member focal power and member spacing, the optical material (such as reflector, glass material, etc.) of each member, the distance of each member, and the The optical power of each team member calculated in the previous step is used to allocate the optical power, and to temporarily allocate the curvature of each surface of each team member. The image quality of the structure obtained at this time is still not good, and the program platform in step 1 needs to write the image quality optimization function in the commercial optical optimization design software to optimize the image quality and fine-tune the curvature and each spacing to achieve Better image quality, and then output the optimized structure.

The optimization of the OMAX control optical system of described step (3) in commercial optical software is characterized in that: the steps are as follows:

⑶-a. Assign the wavelength parameter input by the OMAX user to the commercial optical software;

⑶-b. Directly assign the NA or entrance pupil input by the OMAX user to the commercial optical software;

⑶-c. Assign the glass material input by OMAX to each team member of the commercial optical software in turn;

⑶-d. OMAX is assigned to each group member by the group member interval in the first-order quantity of the group member that claim 3 generates;

⑶-e. Assign the focal power of the team member in the first-order quantity of the team member generated by OMAX to each team member;

⑶-f. Write the constraints of basic design requirements in OMAX in the commercial optical design software, and set the curvature of each surface as a variable for optimization;

⑶-g. OMAX writes reasonable constraints on the spacing between each plane in the commercial optical software, and then sets the spacing of each plane as a variable for optimization, and finally outputs a usable initial structure.

The advantages of the present invention: (1) use the Delano diagram and optimization algorithm to automatically generate the first-order quantity of the optical system; The allocation of optical power and distance is automatically carried out in the design software; (3) through the dynamic data link, the system with allocated optical power and distance is further automatically optimized for the curvature of each team member, and the initial structure is automatically generated (4) This method is a general automatic generation method of the initial structure of the optical imaging lens, and all execution steps are controlled by the program, but for different design requirements, the program calculates the constraints and objective functions in the optimization process by itself.

Description of drawings

Fig. 1 is the realization flowchart of the present invention.

Fig. 2A-Fig. 2C are the system one generated by this scheme, in which Fig. 2A is the first-order quantity, the Delano diagram of the initial structure and the final structure; Fig. 2B is the initial structure; Fig. 2C is the final structure.

Figure 3A-Figure 3E is the second system generated by this scheme, in which Figure 3A is the first-order quantity, the final structure, and the lens Delano diagram of LENSVIEW#6084723; Figure 3B is the final scheme; Figure 3C is LENSVIEW#6084723; Figure 3D is the final scheme Letter of transmission; Figure 3E is the letter of transmission of LENSVIEW #6084723.

Detailed ways

Embodiment 1, a method for automatically generating an initial optical structure based on a Delano graph, the implementation flow chart of the present invention is shown in FIG. 1 . The program in the box on the left that realizes automatic optimization of first-order quantities is temporarily called OMAX. In the OMAX interface, the user needs to input the number of lights, the glass material parameters (refractive index and Abbe number, or glass name) of each team member, and basic design requirements. After inputting these basic parameters, call the optimization algorithm by yourself, and under the constraints of the basic design requirements as the constraint function, optimize the working wavelength of the learning system and the total team member Delano coordinates for design, and obtain the Delano coordinates of each team member Coordinates in the graph. Finding the Delano coordinates of each team member Afterwards, combined with the Delano diagram's The relationship between coordinates and all other first-order quantities, the optical power and distance between each team member are automatically obtained in OMAX. Establish a communication dynamic data link between the OMAX platform and commercial optical optimization design software. First read in the wavelength parameters, the glass parameters of each team member and the field of view parameters from OMAX. Insert each team member in the commercial optical optimization design software in turn, and assign glass parameters and the spacing parameters of each team member. At this time, each team member may be a reflector or a lens group. According to the focal power parameters in the first-order quantities of each team member obtained by OMAX, for reflectors, the radius of curvature can be directly assigned to them, and for refraction materials, the curvature of one of the surfaces is temporarily set to infinity, and then the other surface is changed The curvature is such that the optical power of the group member obtained in OMAX is satisfied. According to this rule, the commercial software is controlled by the OMAX program platform to distribute the optical power of all team members. After assigning the optical power, for the refractive material, each team member also has a surface whose radius of curvature can be adjusted to improve image quality. At this time, use the OMAX program to write the constraints of the basic design requirements in the commercial optical design software, generally including the designed focal length, entrance pupil diameter, etc. If there is a reflective surface, set the range of the conic coefficient of the reflective surface. The curvature of each surface is controlled by OMAX and set as an optimized variable in turn, and the system is optimized by calling the built-in optimization function in the commercial optical optimization design software through OMAX. After optimizing the curvature of each surface, use the OMAX platform to write a reasonable constraint function for the spacing of each group member in the commercial optical software, and then set the spacing between each group member as a variable, and then use OMAX to call the commercial optical design software The built-in optimization function in optimizes the image quality and realizes the optimization of the pitch. Obtain the first-order quantity of each team member through the optimization of the Delano coordinates of each team member of the required optical system through the above-mentioned OMAX, and then establish a dynamic data link between OMAX and the commercial optical optimization design to quickly work in the commercial optical optimization software The wavelength band, entrance pupil aperture, field of view, glass material of each team member, and distribution of focal power of each team member can obtain a rough optical structure. Then use OMAX to automatically optimize the curvature and spacing of each team member, and we can quickly get a reasonable initial structure for a given design degree of freedom (determined by the number of initial design team members).

Figure 2 below shows the design of a two-mirror system by applying the method of the present invention. Fig. 2A is the Delano diagram of the first-order quantity generated in OMAX, the Delano diagram of the initial structure generated by the commercial optical software controlled by OMAX, and the Delano diagram of the final structure after optimizing the initial structure. Fig. 2B is the initial structure of the two-mirror system, and Fig. 2C is the final structure of the two-mirror system. A reasonable initial structure and a final structure can be quickly obtained through the combination of the Delano graph proposed in the present invention and the optimization algorithm.

In order to test the method's ability to design complex systems, the design shown in Figure 3 is carried out. In the optical system, the lithography objective lens is a kind of extremely complex system, requiring large NA, small distortion, and large field of view. In LENSVIEW, we can find the lithography lens of #6084723, which has 28 members. This is an extremely complex design work for optical design. Extract the basic design requirements corresponding to #6084723 (focal length, NA, object field of view, image field of view, entrance pupil aperture), and the operating wavelength and other parameters, input them into the OMAX interface, and optimize the Delano coordinates, you can get the figure For the black curve in 3A, all the first-order quantities are obtained according to the obtained Delano coordinates, and the focal power allocation, curvature optimization, and spacing optimization are performed in commercial optical optimization design software to obtain the final system parameters. The first-order quantity obtained by OMAX, the final system, and the Delano curve of lens #6084723 in LENSVIEW are shown in 3A. 3B is the layout diagram of the optical system of the final solution obtained, and 3C is the layout diagram of the optical system of the #6084723 lens as a comparison. 3D is the MTF transfer chart of the final solution obtained by applying the present invention, and 3E is the MTF transfer chart of the #6084723 lens. By comparing the lens designed by the method provided by the present invention with the existing complex lithography lens, it can be found that its high efficiency and practicability in complex lens design.

Claims (7)

1. A method for automatically generating optical initial structures based on Delano diagrams, characterized in that the working steps are followed by (1) the optimal design of optical first-order quantities, (2) the automatic distribution of first-order quantities and optical materials in commercial optical optimization software, ⑶. The automatic optimization of image quality is realized in three steps. 2. the optical initial structure automatic generation method based on Delano diagram according to claim 1, it is characterized in that, the optimal design of described step (1) optical first-order quantity is based on Delano diagram, for _y Coordinates, optimized with the design requirements as constraints, according to the optimized y _i Coordinates and y _i in Delano The relationship between the coordinates and other first-order quantities, to obtain all first-order quantities of each team member of the system; all first-order quantities depend on the Delano graph pair y _i optimization is completed. 3. the optical initial structure automatic generation method based on Delano figure according to claim 1, is characterized in that, the distribution of first-order quantity and material in described step (2) commercial optics optimization software is to rely on the first-step optimization platform , establish a dynamic data link between the first step and the optimization platform and commercial optical optimization software to realize the assignment of first-order volume parameters and optical materials. 4. the optical initial structure automatic generation method based on Delano figure according to claim 1, is characterized in that, the automatic optimization of described step (3) image quality also is to depend on the program platform where the first step optimization program is located, in commercial The basic constraints of the design are generated in the optimization software, and then the optimization design objective function and weight function are automatically written, and then the spacing and curvature of each group member are controlled and optimized. 5. the optical initial structure automatic generation method based on Delano figure according to claim 1, is characterized in that, the optimal design of the optical first-order quantity of described step (1): in optical imaging lens design, need to have objective function and Constraint function; the optimized objective function is the size of the deflection angle of light in each team member, or the total length of the system, or a mixture of the two, or other first-order quantities; the optimized constraint function mainly comes from the basic design Requirements, for the design of the finite optical system, the basic design requirements generally include NA, the total focal length of the system, the system object field of view, the image field of view, and the entrance pupil aperture of the system; for the infinite system, the basic requirements of the design are generally There are system focal length, object field of view, and entrance pupil aperture; according to the constraint function obtained from the design goal and the optimized objective function, through the iteration of the optimization algorithm, the incident height and axis of the marginal light emitted by the on-axis points on each team member are continuously optimized The incident height of the chief ray emitted by the outer point minimizes the optimized objective function, thus outputting a set of design objectives y _i value. 6. the method for automatically generating optical initial structures based on Delano diagram according to claim 1, is characterized in that, described step (2) obtains the _y that satisfies the design target value, according to the Delano diagram coordinates y _i The relationship with other first-order quantities of each team member of the optical system is automatically obtained by the program. In order to quickly and efficiently generate the initial optical structure, we need to establish a dynamic data link between the external optimization program platform and the commercial optical optimization design software; in the first step, the optimized y _i value and its member focal power and group member spacing, the optical material of each group member, the distance of each group member, and the distance of each group member calculated according to the previous step are automatically assigned in the commercial optical optimization design software through a dynamic data link. The focal power is assigned to the focal power, and the curvature of each surface of each team member is temporarily allocated; the structural image quality obtained at this time is still not good, and it needs to be controlled by the program platform in step 1 and written in a commercial optical optimization design software. Input the image quality optimization function, optimize the image quality, fine-tune the curvature and each spacing to achieve better image quality, and then output the optimized structure. 7. according to the described optical initial structure automatic generation method based on Delano diagram according to one of claim 1-6, it is characterized in that, the specific operation steps of described step (3) are as follows: ⑶-a. Assign the wavelength parameter input by the OMAX user to the commercial optical software; ⑶-b. Directly assign the NA or entrance pupil input by the OMAX user to the commercial optical software; ⑶-c. Assign the glass material input by OMAX to each team member of the commercial optical software in turn; ⑶-d. OMAX is assigned to each group member by the group member interval in the first-order quantity of the group member that claim 3 generates; ⑶-e. Assign the focal power of the team member in the first-order quantity of the team member generated by OMAX to each team member; ⑶-f. Write the constraints of basic design requirements in OMAX in the commercial optical design software, and set the curvature of each surface as a variable for optimization; ⑶-g. OMAX writes reasonable constraints on the spacing between each plane in the commercial optical software, and then sets the spacing of each plane as a variable for optimization, and finally outputs a usable initial structure.