Multi-parameter optimisation of optical bonding for the ultra-stable optical measurement bench in space-based platform

• Proposed and validated a theoretical modelling approach to analyse multi-parameter effects in hydroxide catalysis bonding. • Increased curing temperature significantly reduces bonding time and enhances bonding strength. • The flat-convex combination exhibited superior strength performance under RMS errors ≤0.6 λ. • Successfully applied to the construction of Chinese "Taiji" ultra-stable optical measurement bench. To enhance the measurement accuracy of space-based platforms, the construction of optical platforms imposes higher performance demands on optical bonding technology. Hydroxide Catalysis Bonding (HCB) technology, with its advantages of low stress and high precision, has emerged as a critical technique for achieving this objective. However, the performance optimisation and application of HCB under multi-parameter influences still require further systematic investigation. This study, using the developed mathematical model and experimental validation, systematically examines the effects of solution concentration, solution volume, curing temperature, and surface shape error on bonding time, strength, and stability. The experiments identified the optimal process parameters: 1:300 Molar ratio, 0.8 μL solution volume, 0.1 λ surface shape error, and a bonding area of 2 cm 2 , while confirming the pronounced impact of high-temperature curing in accelerating bonding time and enhancing bonding strength. The research reveals that a plane-convex combination exhibits superior strength performance under low RMS error (≤0.6 λ), while spot displacement tests indicate that the deflection angle of the bonding structure during curing can be maintained stably within 10 arcsec . Based on the optimised parameters and conclusions, the Chinese “Taiji” ultra-stable optical measurement bench (USOMB) achieved optical bonding, and passed noise stability measurement. The results demonstrate that the platform achieves noise levels below 10 p m / H z in the 0.1 Hz to 1 Hz range, reaching p m / H z at 1 Hz , a reduction of approximately two orders of magnitude compared to “Taiji-1”. These findings provide technical support for the construction of the USOMB in the “Taiji Program”.