Structural optical design of multi-group, high zoom ratio optical systems

In this paper, we propose a method for the structural optical design of multi-group, high zoom ratio optical systems based on matrix optics and Particle Swarm Optimization (PSO) algorithm. This method effectively addresses the problems of initial structural calculation difficulties, large volume, and unsmooth zoom curves with large inflection points in high zoom ratio optical systems. To design the zoom optical system, the matrix equations of the multi-group zoom system are derived using geometric optics; and a mathematical model is built to solve the initial structural parameters of the zoom system based on the matrix. Then, a new fitness function is introduced as an indicator to iteratively optimize the initial structural parameters of the system in multi-dimensional space, considering factors such as maximum zoom ratio, total optical length, and full field of view angle. Finally, this method is validated in two complex optical system designs including a 20x four-group and a 35x five-group zoom optical system, showing strong retrieval capabilities. Independent of traditional trial-and-error investigations for solutions, our method facilitates the automatic intelligent design of complex optical systems.