Astronomical Mirrors and
Large-size optics Manufacturing

To carry out technological and certification testing measurements of large-size optical components up to 6000mm in diameter and 10-70m radius of curvature working surface the specially built test complex UVK-6/70 is widely used. technical characteristics: Chamber height - 78 m Chamber volume - 1600 m3 Chamber diameter - 3-8 m Maximum vacuum level - 1 x 10-3 mm Hg Time of maximum vacuum level attainment - 7 hours Chamber weight - 270 ton Weight of a component under testing - up to 100 ton Test equipment - remotely operated vacuum interferometer To test a surface shape on a real time basis a system of computer-based interferogram processing, which is a television system of interferogram picture signal processing, is used. The system includes CCD unit of photoelectric recording of 1024x1024 pixels.

For testing procedures the following items are also widely used:

• a set of interferometers for surfaces figure testing at all technological stages that consist of computer-controlled photo-electric system of surfaces interference patterns registration and processing;
• a range of vibration-isolated test stands and technological supporting mounts of membrane-pneumatic type to support and stabilize a surface shape of optical components on stages of their treatment and testing, including automatic maintenance of adjustment parameters when environment factors are changed (atmospheric pressure, temperature);
• a system of technological software KCPM and AD2 used for processing a wave-front interference patterns of a tested component on a real time basis, calculating technological parameters of computer-controlled figuring, automatic correction of figuring process according to the results of a computerized treatment session, forecasting a surface shape to be reached.