Calculating and optimizing the parameters of a laminated radial gradient-index lens subjected to polychromatic radiation under temperature fluctuations

Subject of study. A radial gradient-index lens (RGL) in an infinitely thin objective model is studied. Aim of study. This study aims to develop a method for calculating and optimizing the parameters of a laminated RGL in an infinitely thin objective model and a method for optimizing the calculated parameters during the automatic aberration correction of an optical system operating in the mid- and long-wavelength infrared spectral ranges under temperature fluctuations. Method. Theoretical analysis and mathematical modeling were performed using geometric optics equations. Main results. A method for numerically determining the characteristics of an RGL was proposed. When combined with other optical elements, the calculated characteristics of the RGL ensured constant optical power of an infinitely thin objective model at three wavelengths within the spectral range and at the boundary values of the temperature interval. Equations were derived to calculate the parameters of an RGL and used to develop a macro integrated into the optimization function of a commercial optical design program. The developed macro enables the automatic aberration correction of an objective equipped with an RGL subjected to polychromatic radiation under temperature fluctuations. The effectiveness of the proposed macro was demonstrated by using it to automatically correct the aberration of the axial ray bundle in an objective with an RGL during the transition from an infinitely thin model to finite-thickness elements. Practical significance. The proposed methodology can facilitate the acquisition of the structural parameters of the initial optical layout during the preliminary design of an objective equipped with an RGL.