Method and device for preventing dew condensation and frosting on optical glass window

摘要

A method and an apparatus are provided for preventing formation of dew and/or ice on an optical glass window, with which formation of dew and/or ice is easily and simply prevented while an air turbulent disturbance is minimized and a deformation is inhibited as little as possible. A protective tube ( 6 ) covering an external atmosphere of a cooled optical glass window ( 2 ) and thermally insulated from the optical glass window ( 2 ) is provided so as to prevent the external atmosphere from being cooled in order to prevent the optical glass window ( 2 ) from having dew and/or ice formed thereon.