The aperture of a lens.
An example of an aperture is the opening in a camera lense.
- an opening; hole; gap
- the opening, or the diameter of the opening, in a camera, telescope, etc. through which light passes into the lens
Origin of apertureClassical Latin apertura ; from apertus, past participle of aperire, to open ; from Indo-European an unverified form ap-wer-, to uncover ; from base an unverified form ap(o)-, away + an unverified form wer-, to close, cover from source warn
- An opening, such as a hole, gap, or slit.
- a. A usually adjustable opening in an optical instrument, such as a camera or telescope, that limits the amount of light passing through a lens or onto a mirror.b. The diameter of such an opening, often expressed as an f-number.c. The diameter of the objective of a telescope.
Origin of apertureMiddle English, from Latin apert&umacron;ra, from apertus, past participle of aper&imacron;re, to open; see wer-4 in Indo-European roots.
- An opening; an open space; a gap, cleft, or chasm; a passage perforated; a hole; as, an aperture in a wall.
- An aperture between the mountains. --Gilpin.
- The back aperture of the nostrils. --Owen.
- (optics) Something which restricts the diameter of the light path through one plane in an optical system.
- (astronomy, photography) The diameter of the aperture (in the sense above) which restricts the width of the light path through the whole system. For a telescope, this is the diameter of the objective lens. e.g. a telescope may have a 100 cm aperture.
- (spaceflight, communication) The (typically) large-diameter antenna used for receiving and transmitting radio frequency energy containing the data used in communication satellites, especially in the geostationary belt. For a comsat, this is typically a large reflective dish antenna; sometimes called an array.
- (mathematics, rare, of a right circular cone) The maximum angle between the two generatrices.
- If the generatrix makes an angle θ to the axis, then the aperture is 2θ.
The aperture of microscopes is often expressed in degrees, called also the angular aperture, which signifies the angular breadth of the pencil of light which the instrument transmits from the object or point viewed; as, a microscope of 100° aperture.
aperture - Computer Definition
(2) (Aperture) A photo editing and management application for the Mac from Apple. Introduced in 2005 and used by professional photographers, Aperture provides sophisticated touch-up tools and works with the iPhoto library. See iLife.