| 释义 |
Cassegrainian, a.|kæsɪˈgreɪnɪən|
Applied to a modification of the Gregorian reflecting telescope suggested in 1672 by M. Cassegrain. Also Cassegrain, used attrib. and absol.
1813Kater in Phil. Trans. No. 206 (title) On the light of the Cassegrainian Telescope, compared with that of the Gregorian. 1831Brewster Optics xlii. 352 The Cassegrainian telescope..differs from the Gregorian only in having its small speculum..convex instead of concave. 1888Encycl. Brit. XXIII. 145/1 The Cassegrain telescope... In comparatively recent years the Cassegrain has acquired importance from the fact of its adoption for the great Melbourne telescope. 1961Listener 7 Sept. 353/3 The Cassegrain mirror is swung down into a compartment let into the telescope tube. |