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To solve some astronomical problems and the problems of atmospheric sounding, it is necessary to apply high-quality optical antennas because the quanlity of the optics determines the error at the parameter measuring. An intrinsic feature of the process of optical pieces manufacturing is the control of the quality of their shape at the production. Interferometry is one of the most precise methods for optical testing. The main difficulties in the control of the shape of optical surfaces are connected to the compensation of the aberrations of optical systems used to form the preset wavefront on the surface of the piece under control. When the aberrations are present in the object branch, the deformation of the interferometric fringes occurs even in case of a complete correspondence of the wavefronts of the object wave and the comparison wave. The appearance of the residual aberration is conditioned by the error of the manufacture of the elements of the illuminating branches, the remainder of the calculation and adjustment error. It is impossible to completely compensate for the residual aberration by introducing stringent manufacture and adjustment tolerances. That is why an optical system that forms the reference wavefront should possess a limited minimum value of the residual wave aberration. It is suggested to use a versatile adaptive mirror based on a bimorphed piezoelectric element as technical means for residual aberration correction. By selecting suitable controlling stresses, one may reach a rather good simulation of the geometric and wave aberrations to decrease the value of the residual aberration of the illuminating branch of the interferometer, thus increasing the precision of the interferometric control. The experimental results in the design of a real interferometer are given and discussed.
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