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aperture
ap·er·ture A0361900 (ăp′ər-chər)n.1. An opening, such as a hole, gap, or slit.2. 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.
[Middle English, from Latin apertūra, from apertus, past participle of aperīre, to open; see wer- in Indo-European roots.]
ap′er·tur′al adj.aperture (ˈæpətʃə) n1. a hole, gap, crack, slit, or other opening2. (General Physics) physics a. a usually circular and often variable opening in an optical instrument or device that controls the quantity of radiation entering or leaving itb. the diameter of such an opening. See also relative aperture[C15: from Late Latin apertūra opening, from Latin aperīre to open]ap•er•ture (ˈæp ər tʃər)
n. 1. an opening, as a hole, slit, or gap. 2. Also called ap′erture stop`. an opening, usu. circular, that limits the quantity of light that can enter an optical instrument, as the lens of a camera. [1400–50; late Middle English < Latin apertūra=apert(us), past participle of aperīre to open (see aperient) + -ūra -ure] ap′er•tured, adj. Thesaurus| Noun | 1. |  aperture - a device that controls amount of light admittedcamera, photographic camera - equipment for taking photographs (usually consisting of a lightproof box with a lens at one end and light-sensitive film at the other)regulator - any of various controls or devices for regulating or controlling fluid flow, pressure, temperature, etc.telescope, scope - a magnifier of images of distant objects | | 2. |  aperture - a natural opening in something eye, oculus, optic - the organ of sightpupil - the contractile aperture in the center of the iris of the eye; resembles a large black dothole - an opening into or through somethingmicropyle - minute opening in the wall of an ovule through which the pollen tube entersstoma, stomate, pore - a minute epidermal pore in a leaf or stem through which gases and water vapor can pass | | 3. |  aperture - an man-made opening; usually small embouchure, mouthpiece - the aperture of a wind instrument into which the player blows directlymouthpiece - a part that goes over or into the mouth of a person; "the mouthpiece of a respirator"opening - a vacant or unobstructed space that is man-made; "they left a small opening for the cat at the bottom of the door" |
aperturenoun opening, space, hole, crack, gap, rent, passage, breach, slot, vent, rift, slit, cleft, eye, chink, fissure, orifice, perforation, eyelet, interstice Through the aperture he could see daylight.aperturenounAn open space allowing passage:hole, mouth, opening, orifice, outlet, vent.Translationsaperture (ˈӕpətjuə) noun1. an opening or hole. 開孔 孔2. (the size of) the opening (eg in a camera) through which light passes. 孔徑，(相機的)光圈 孔径，（照相机的）光圈 aperture
aperture Physicsa. a usually circular and often variable opening in an optical instrument or device that controls the quantity of radiation entering or leaving it b. the diameter of such an opening aperture The diameter of the unobscured portion of the objective lens in a refracting telescope or of the primary mirror in a reflector. In a radio telescope it is the physical size of the antenna. As the aperture is increased, the telescope gathers more light, radio waves, etc., and thus will discern fainter objects: the radiation-gathering power depends on area, i.e. on the square of the aperture. A larger aperture also produces a smaller Airy disk and so has greater spatial resolution.ApertureAn opening for the purpose of admitting light. aperture[′ap·ə‚chər] (electronics) An opening through which electrons, light, radio waves, or other radiation can pass. (graphic arts) A rectangular cutout on an aperture card. (optics) The diameter of the objective of a telescope or other optical instrument, usually expressed in inches, but sometimes as the angle between lines from the principal focus to opposite ends of a diameter of the objective. aperture(1) An orifice. It often refers to an opening in which light is allowed to pass in optical systems such as cameras and lasers. See f-stop and numerical aperture.
(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.aperture
aperture [ap´er-chur] opening.inferior aperture of minor pelvis (inferior aperture of pelvis) pelvic outlet.numerical aperture an expression of the measure of efficiency of a microscope objective.superior aperture of minor pelvis (superior aperture of pelvis) pelvic inlet.ap·er·ture (ap'er-chūr), 1. Opening. An inlet or entrance to a cavity or channel. In anatomy, a gap or hole.
See also: fossa, ostium, orifice, pore. Synonym(s): apertura [TA]2. The diameter of the objective of a microscope. Synonym(s): aditus [TA] [L. apertura, an opening] ap·er·ture (ap'ĕr-chŭr) [TA] 1. An inlet or entrance to a cavity or channel; in anatomy, an open gap or hole. 2. The diameter of the objective of a microscope.
Synonym(s): aditus [TA] , apertura [TA] . [L. apertura, an opening]aperture An opening, or the area of a lens, through which light can pass. See pupil.
angular aperture Half of the maximum plane subtended by a lens at the axial point of an object or image. (Sometimes the full plane angle is taken as the angular aperture but this is not convenient in optical calculations.) See sine condition.
aperture of a lenticular lens That portion of a lenticular lens which has the prescribed power (British Standard).
numerical aperture An expression designating the light-gathering power of microscope objectives. It is equal to the product of the index of refraction n of the object space and the sine of the angle u subtended by a radius of the entrance pupil at the axial point on the object, i.e. n sin u.
palpebral aperture The gap between the margins of the eyelids when the eye is open. An abnormal increase in the aperture occurs in some conditions, including Graves' disease, buphthalmos, Parinaud's syndrome and retrobulbar tumour. An abnormal decrease in the aperture occurs in some conditions, including ptosis, microphthalmos and ophthalmoplegia (Figs. A15 and A16). Syn. interpalpebral fissure (this term is more accurate although used infrequently); palpebral fissure. See exophthalmos.
aperture plane See aperture plane.
aperture ratio See relative aperture.
relative aperture The reciprocal of the f number. It is therefore equal to the ratio of the diameter of the entrance pupil to the primary focal length of an optical system. Syn. aperture ratio. Note: the definition of this term is not universally accepted; some authors define it as the reverse of the above. See antimongoloid slant; f number. " > Fig. A15 Palpebral aperture PA and corneal apex CA" > Fig. A16 Average dimensions of the normal palpebral aperture of a Caucasian eyeap·er·ture (ap'ĕr-chŭr) [TA] 1. [TA] Opening. An inlet or entrance to a cavity or channel. In anatomy, a gap or hole.
Synonym(s): apertura. 2. The diameter of the objective of a microscope.
See also: fossa, ostium, orifice
Synonym(s): aditus [TA] . [L. apertura, an opening]aperture
Related to aperture: Shutter speedSynonyms for aperturenoun openingSynonyms- opening
- space
- hole
- crack
- gap
- rent
- passage
- breach
- slot
- vent
- rift
- slit
- cleft
- eye
- chink
- fissure
- orifice
- perforation
- eyelet
- interstice
Synonyms for aperturenoun an open space allowing passageSynonyms- hole
- mouth
- opening
- orifice
- outlet
- vent
Words related to aperturenoun a device that controls amount of light admittedRelated Words- camera
- photographic camera
- regulator
- telescope
- scope
noun a natural opening in somethingRelated Words- eye
- oculus
- optic
- pupil
- hole
- micropyle
- stoma
- stomate
- pore
noun an man-made openingRelated Words- embouchure
- mouthpiece
- opening
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