The Collaborative International Dictionary of English. 2000.
Subtended arc — In geometry, an arc subtended by an angle is a curve whose endpoints are on the angle s two rays. The precise meaning varies with the context. For example, one may speak of the arc of a circumference subtended by an angle whose vertex is a point… … Wikipedia
subtended — v. be opposite to (Mathematics); lie beneath, extend under … English contemporary dictionary
Solid angle — The solid angle, Ω , is the angle in three dimensional space that an object subtends at a point. It is a measure of how big that object appears to an observer looking from that point. For instance, a small object nearby could subtend the same… … Wikipedia
Parallax — For other uses, see Parallax (disambiguation). A simplified illustration of the parallax of an object against a distant background due to a perspective shift. When viewed from Viewpoint A , the object appears to be in front of the blue square.… … Wikipedia
Radian — For other uses, see Radian (disambiguation). mrad redirects here. For millirads, see Rad (unit). An angle of 1 rad … Wikipedia
eye, human — ▪ anatomy Introduction specialized sense organ capable of receiving visual images, which are then carried to the brain. Anatomy of the visual apparatus Structures auxiliary to the eye The orbit The eye is protected from mechanical injury… … Universalium
Circle — This article is about the shape and mathematical concept. For other uses, see Circle (disambiguation). Circle illustration showing a radius, a diameter, the centre and the circumference … Wikipedia
Radiance — For other uses, see Radiance (disambiguation). Radiance and spectral radiance are radiometric measures that describe the amount of radiation such as light or radiant heat that passes through or is emitted from a particular area, and falls within… … Wikipedia
Visual acuity — 20/15 and 20/15 vision redirect here. For other uses, see 2020 (disambiguation). Typical Snellen chart used for visual acuity testing. Visual acuity (VA) is acuteness or clearness of vision, which is dependent on the sharpness of the retinal… … Wikipedia
angular magnification — noun : the ratio of the angle subtended at the eye by the image formed by an optical instrument to that subtended at the eye by the object when not viewed through the instrument * * * Optics. the ratio of the angle subtended at the eye by the… … Useful english dictionary
