Theoretical modeling and calculation of stress fields in precision optical lens subjected to multi-point adhesive bonding assembly

In optical precision assembly, most optical components are fixed by multi-point adhesive bonding. However, the stress fields generated in lenses by radial stress in the adhesive significantly influence the imaging quality of precision optical lenses. To date, the adhesive bonding process is conducted empirically, meaning that the stress in lenses cannot be actively or quantitatively controlled. Therefore, to improve the current passive process, a theoretical mechanical model of an optical lens was established, and a novel stress potential function was proposed to derive the analytical solution of stress components in lenses under an arbitrary number of multi-point radial stresses. The results revealed a quantitative relationship between the radial stress in the adhesive and the stress field in the optical lens. Furthermore, a new experimental device was developed, and a systematic experimental method was proposed to apply multi-point quantitative radial loads on an optical lens and measure its real-time stress distribution, which further verifies the accuracy and validity of the proposed theoretical model. This study provides a theoretical approach for the quantitative control of lens stress and optimization of adhesive bonding configuration in optical precision assembly process, which is a basis to enhance the imaging accuracy of precision optical instruments.