- zonal aberration
- unequal refraction of light rays by a lens, the rays passing through different zones being focused at different distances from the lens.
Medical dictionary. 2011.
Medical dictionary. 2011.
spherical aberration — spher·i·cal aberration sfir i kəl , sfer n aberration that is caused by the spherical form of a lens or mirror and that gives different foci for central and marginal rays * * * zonal aberration in relation to an axial point; see negative… … Medical dictionary
Deformable mirror — A deformable mirror can be used to correct wavefront errors in an astronomical telescope … Wikipedia
international relations — a branch of political science dealing with the relations between nations. [1970 75] * * * Study of the relations of states with each other and with international organizations and certain subnational entities (e.g., bureaucracies and political… … Universalium
Europe, history of — Introduction history of European peoples and cultures from prehistoric times to the present. Europe is a more ambiguous term than most geographic expressions. Its etymology is doubtful, as is the physical extent of the area it designates.… … Universalium