In order to improve dynamic range and effective bandwidth of the correlation tracker in a space solar telescope

the beryllium was optimally chosen as a space mirror material to fabricate a tip-tilt mirror of correlation tracker. The finite element model of the beryllium mirror was established and the mechanical properties of the tip-tilt mirror under inertia and temperature loads was analyzed. Then

the surface figure and inner stress of the tip-tilt mirror under different working conditions were investigated. Finally

the mechanical properties between same structure mirror of beryllium and silicon carbide were compared. The analysis results show that the final RMS surface figure error of 2.18×10

-6

mm and PV of 1.69×10

-5

mm are obtained

the resonant frequency is 1 609 Hz. The beryllium mirror substrate has already obtained

and its optics process is proceeding. The results indicate that analysis results satisfy the technology requirements of the tip-tilt mirror of the correlation tracker. The inner stress of the mirror is less than yield strength of beryllium material when the tip-tilt is under inertia and temperature loads

the analysis results of beryllium tip-tilt mirror are better than that of silicon carbide tip-tilt mirror.