Automatically retrieving an initial design of a double-sided telecentric zoom lens based on a particle swarm optimization.

In this paper, we propose an efficient and robust approach to retrieve an optimal first-order design of a double-sided telecentric zoom lens based on the particle swarm optimization (PSO) algorithm. In this method, the design problem is transformed to realize a zoom system with fixed positions of both the front focal point and the rear focal point during zooming. Equations are derived for the paraxial design of the basic parameters of a three-component zoom lens in the framework of geometrical optics. We implement the PSO algorithm in MATLAB to design some test cases to verify the feasibility. As the computational work is completed by the optimization algorithm, instead of the traditional trial-and-error method, our proposed method is efficient and low-threshold. By a simulation result, it is verified that the described method is stable and necessary in finding a proper initial configuration of a zoom lens with two fixed foci as well as a required zoom ratio. Furthermore, a compact initial design of a three-component 2X zoom system with two fixed foci is proposed. Based on the initial design data, a double-sided telecentric zoom system is developed. The result shows the great potential of our proposed method in retrieving proper initial designs of complex optical systems.