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Large-aperture telescope can be used in surveying battlefield, researching landform, searching object, real-time
monitoring, imaging, detecting and identifying spatial targets and so on. A large-aperture telescope for achieving high
resolution power is designed to monitor spatial target and image in real time. Real-time monitoring plays an important
role in military conflicts. The orbit parameter of object, quantity, geometrical shape parameter and so on can be obtained
by detect spatial target. With the development of optical technology, people require larger aperture in optics-electronic
(O-E) system. By increasing optical aperture, the ability of collecting light and resolution power in the system can be
enhanced. But the support structure of the primary mirror of large-aperture telescope will be a very difficult problem.
With the increase of primary mirror aperture, the weight of the primary mirror will become larger than before. The root
mean square (rms) of the primary mirror is affected by many factors, such as deadweight, deformation of heat,
environment and so on. Due to the primary mirror of telescope is an important component of telescope system. By
reducing the weight of primary mirror, precision of the system is ensured. During the designing phase, one can consider
the supporting project of the primary mirror synthetically and analyze it roundly according to technical requirement of
optical system and the effect factors. The final structural design can be reasonable.
In an astronomical telescope, the surface of reflector is an important part for collecting dark radiation of celestial bodies.
Its surface shape will have an effect on collecting efficiency of telescope radiant energy directly. So the rms must be very
high. Optical system of large aperture, small wavelength and small focus can receive maximal light intensity. For
ground-based optical astronomical telescope, the design proposed in the paper can satisfy the requirement of the possible
minimum atmosphere seeing at astronomical observatory site and exert the use efficiency of the telescope adequately. So
the accuracy of the traditional surface of reflector can assure that 90% of all the light energy can be focused on within the
angle diameter range of the minimum atmosphere seeing, then 100% of light energy should be focused on the angle
diameter range of minimum atmosphere seeing. Because the rms of mirror is very high, precise surface machining and
accurate the support of mirror are very important tasks during designing and manufacturing the telescope.
In the paper, various support techniques of a large-aperture telescope primary mirror are discussed and a 3.5 meter
telescope system at the Starfire Optical Range (SOR) overviewed simply, which was operated by the Directed Energy
Directorate of the Air Force Research Laboratory, Kirtland AFB, NM, USA from the ground-based O-E system for the
observations of spatial target. We also analyze Theoretical elastic deformation of the Steward Observatory 2.3 meter
mirror is analyzed.
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