Abstract: One of the major problems to retain the efficiency of atelescope is to achieve and maintain high reflectivityin the wide wavelengths of the coatings of thetelescope optics. For coating the large mirrors ofSubaru Telescope, we employed the conventionalevaporation scheme, in the expectation of uniformcoverage of the film. In this paper, we will report theinstallation and the performance verification of thecoating facility. This facility consists of a washingtower for stripping off the old coating, an evaporationcoating chamber, two trolleys and a scissors- likelifter for handling the primary mirror. To supply alarge number of filaments loaded with uniform qualitymolten metal, the practical solution is to pre-wet thefilaments with the agent metal and keep them in acontrolled manner before the evaporation. The aluminumfilm deposit on the test samples in the 8.3 m coatingchamber proved the film thickness uniformity matchingwith the specification. Reflectivity of the freshsurface was over 90% at visible wavelength. InSeptember 1997, we re-aluminized 1.6 m and 1.3 mmirrors for the first time (at least for ourselves)application to the real astronomical telescopes. Theresultant surface reflectivity confirmed thefeasibility of using pre-wetted filaments.!7
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