‖ polyoptron, -um
(pɒlɪˈɒptrən, -əm)
[mod.L., f. Gr. πολυ-, poly- + -οπτρον, naming instruments of sight: see diopter.]
An optical instrument through which objects appear multiplied; a multiplying-glass (see quot. 1842). Cf. polyscope 1.
| 1727–41 Chambers Cycl., Polyoptrum,..a glass through which objects appear multiplied, but diminished. 1842 Brande Dict. Sc., etc., Polyoptron, in Optics, a glass through which objects appear multiplied, but diminished. It consists of a lens one side of which is plane, but in the other are ground several spherical concavities. |