zonal aberration

См. также в других словарях:

• 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

• 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