释义 |
polyzonal, a.|pɒlɪˈzəʊnəl| [f. poly- + zonal.] Applied to a form of lens invented by Brewster, composed of a number of annular segments or zones; chiefly used in lighthouses.
1831Brewster Optics xxxviii. 323 Those compound lenses, to which I have given the name of polyzonal lenses. 1863Tyndall Heat xvii. 504 With a large polyzonal lens, Melloni converged an image of the moon upon his pile. c1865J. Wylde in Circ. Sc. I. 258/2 A polyzonal lens, such as was employed..at the South Foreland lighthouse. |