| 摘要 |
<p>A mirror blank including a shell (1) of glass or ceramics, the shape of which substantially corresponds to that of the finished mirror, and a support structure which forms a three-dimensional network which is fastened to the shell and fills the latter. The novelty of the invention consists in the support structure including fibres (3) of a material the coefficient of thermal expansion of which is adapted to that of the shell and a binder which firmly connects the fibres with each other and with the shell. By using fibres the coefficient of thermal expansion of which is greater than that of the shell the mirror blank may have an initial stress imparted to it.</p> |
