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Image-stabilization systems are widely used during astronomical image integration because of their large gain of image
quality and relatively simple control system. Probably the simplest system is the one that tilts a mirror to correct angular
variations caused by atmospheric fluctuations, vibration tilt of the telescope, or angular errors of internal components.
Lightweight (structured) mirrors based on piezoelectric actuators are of important part of these systems. The coating of
lightweight (structured) mirrors and the associated support systems involves the prediction of the magnitude and nature
of the elastic deformation of mirror surface due to mechanical and thermal residual stress during coating. The clamping
ways are firstly analyzed in this paper, and the finite element method of structural analysis makes it possible to include
conveniently the deformation and stress of a lightweight mirror in consideration of effects of thermal gradients and
mechanical loads during coating. Two models with different clamping ways are set up by using FEA soft. The
distribution of deformation and stress of lightweight mirror caused by thermal residual stress is analyzed. The coated
lightweight mirror is measured by interferometer and the result shows the calculated and measured results have good
compatibility. Based on the results of these studies, we select a better clamping way to coating the lightweight mirror.
The lightweight mirror for astronomical telescope intensified with silver has good optical properties, but the silver mirror
has the faults of weak adhesion to glass substrate and the mirror is easily corroded by atmospheric pollution. In order to
solve this problem, several silver adhesion layers are studied. Due to mutual action of Al2O3 and silver film, the
developed Al2O3-based silver intensified mirror has overcome the above faults and achieved good effect. Finally, the
coating is measured by making use of spectrometer. The average reflectance of coating is greater than 98% in 400-1500nm range, and the lightweight mirror can satisfy practical requirement.
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