a field lens is
51Field emission display — A field emission display (FED) is a display technology that incorporates flat panel display technology that uses large area field electron emission sources to provide electrons that strike colored phosphor to produce a color image as a electronic …
52field — I. noun Etymology: Middle English, from Old English feld; akin to Old High German feld field, Old English flōr floor more at floor Date: before 12th century 1. a. (1) an open land area free of woods and buildings (2) an area of land marked by the …
53Field camera — A field camera is a view camera that can be folded in a compact size. Modern designs are little different from the first folding field cameras from the 19th century. In general they have more limited camera movements than the monorail cameras… …
54field — A definite area of plane surface, considered in relation to some specific object. [A.S. feld] auditory f. the space included within the limits of hearing of a definite sound, as of a tuning fork …
55Field of view (image processing) — The field of view of an imaging sensor or imaging system is defined as the maximum vertical and horizontal angular extent viewed by the sensor or system. Optical tests for measuring the FOV are versatile tests capable of measuring the FOV of UV,… …
56lens — n 1. eyepiece, Optics. ocular, Optics. objective, Optics. object glass or lens; telescope, field glass, spy glass; magnifier, magnifying glass, glass, hand lens, loupe; monocle, eyeglass. 2. lenses binoculars, opera glasses, lorgnette; eyeglasses …
57field and field of view — A background area or an entire physical plane, often of one color and/or texture. Also, a sphere of activity, or a content, or a discourse. And, the area in which an image is rendered by the lens of an optical instrument; also called field of… …
58field stop — noun : a diaphragm that determines the size of the field of an optical instrument * * * Optics. the aperture that limits the field of view of a lens or system of lenses …
59field stop — Optics. the aperture that limits the field of view of a lens or system of lenses. * * * …
60field of vision — range of vision, visual field, area visible through the lens of an optical instrument, area which one can see …
