refracting surface
31aplanat — n. a reflecting or refracting surface made aplanatic by correction. Etymology: G …
32axis of incidence — noun The line passing through the point of incidence of a ray perpendicularly to the refracting surface • • • Main Entry: ↑axis …
33vir|tu|al — «VUR chu uhl», adjective. 1. being something in effect, though not so in name; for all practical purposes; actual; real: »The battle was won with so great a loss of soldiers that it was a virtual defeat. 2. Optics. a) of or having to do with an… …
34telescope — /tel euh skohp /, n., adj., v., telescoped, telescoping. n. 1. an optical instrument for making distant objects appear larger and therefore nearer. One of the two principal forms (refracting telescope) consists essentially of an objective lens… …
35History of the telescope — The earliest known working telescopes appeared in 1608 and are credited to Hans Lippershey and Zacharias Janssen, spectacle makers in Middelburg, and Jacob Metius of Alkmaar. The design of these early refracting telescopes consisted of a convex… …
36Optical telescope — Eight Inch refracting telescope (Chabot Space and Science Center) An optical telescope is a telescope which is used to gather and focus light mainly from the visible part of the electromagnetic spectrum for directly viewing a magnified image for… …
37angle — The meeting point of two lines or planes; the figure formed by the junction of two lines or planes; the space bounded on two sides by lines or planes that meet. For angles not listed below, see the descriptive term; e.g., axioincisal, distobuccal …
38light — light1 lightful, adj. lightfully, adv. /luyt/, n., adj., lighter, lightest, v., lighted or lit, lighting. n. 1. something that makes things visible or affords illumination: All colors depend on light. 2. Physics …
39Nonimaging optics — (also called anidolic optics)[1][2] is the branch of optics concerned with the optimal transfer of light radiation between a source and a target. Unlike traditional imaging optics, the techniques involved do not attempt to form an image of the… …
40Eye — For other uses, see Eye (disambiguation), Ocular (disambiguation), Ocular, and Oculus. For taxon specific articles, see human eye, simple eye in invertebrates, mollusc eye, and arthropod eye. Eye …
