To provide control of the whole surface the shell should be rotated. But the shell center beating within 1 μm gives thickness variations from 90 to 1200 Å. For high accuracy of measurements it is necessary to decrease the shell center beating upon rotation down to 0.1–0.2 μm. This problem can be solved using the proposed method for rotation of shells.
Several units for rotation of shells have been developed and investigated. Those laws of rotation have been selected which allow to inspect the whole surface of the sell.
Obvious advantages of the proposed method are the following: ease of installation and removal of the shell in the unit, automated installation of the shell in the desired position, high speed of rotation, small beating of the shell center during its rotation, wide access to the shell surface to be controlled, any required law of the shell rotation.