Aperture vs. Orifice — What's the Difference?

In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture and focal length of an optical system determine the cone angle of a bundle of rays that come to a focus in the image plane.

An opening, especially to a cavity or passage of the body; a mouth or vent.

An opening, such as a hole, gap, or slit.

A mouth or aperture, such as of a tube, pipe, etc.; an opening.

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.

A stupid or objectionable person.

The diameter of such an opening, often expressed as an f-number.

A mouth or aperture, as of a tube, pipe, etc.; an opening; as, the orifice of an artery or vein; the orifice of a wound.

The diameter of the objective of a telescope.

An aperture or hole opening into a bodily cavity;

A small or narrow opening, gap, slit, or hole.

(optics) A hole which restricts the diameter of the lightpath through one plane in an optical system.

The diameter of such a hole which restricts the width of the lightpath through the whole system. For a telescope, this is the diameter of the objective lens.

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.

The maximum angle between the two generatrices.

The act of opening.

An opening; an open space; a gap, cleft, or chasm; a passage perforated; a hole; as, an aperture in a wall.

The diameter of the exposed part of the object glass of a telescope or other optical instrument; as, a telescope of four-inch aperture.

A device that controls amount of light admitted

A natural opening in something

An man-made opening; usually small