Design and verification of adhesive layer for detector assembly of space optical payload

To meet the high-resolution imaging requirements of space-based optical payloads and address the challenge of ensuring reliable bonding between detectors and structural frames under extreme environmental conditions, this paper proposes a collaborative optimization scheme for the bonding of detector assemblies. Firstly, in accordance with the space environmental adaptability requirements of optical payloads, a systematic comparison of the core performance characteristics of commonly used adhesives was conducted. Epoxy resin was adopted as the primary bonding agent to ensure rigid and dependable attachment between the imaging unit and the support frame, while silicone rubber was employed to provide stress-buffering capability, forming a composite adhesion architecture. Subsequently, a multiphysics coupled simulation model was developed to investigate the influences of static mechanical loads and PCB soldering thermal conduction (200°C) on the stress, strain, and displacement of the photosensitive surface of the device while achieving quantitative control of adhesive. Finally, the reliability and stability of the scheme were verified through environmental testing. The results demonstrate that the closed-loop design effectively resolves the challenge of high-precision assembly. Pre- and post-test inspection using a coordinate measuring machine confirmed a coplanarity precision of 0.019 mm, a linearity precision of 0.0021 mm, and an overlap precision better than 0.005 mm. These performance levels satisfy the splicing accuracy requirements for detector components in space optical applications, providing a standardized technical foundation for the precision bonding of this type of detector component and holding significant engineering application value.