English Dictionary

aperture

/ˈap.ə.t͡ʃə/

noun

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 camera's aperture controls the amount of light that enters the lens.

意味（1）

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

an aperture in a wall

意味（2）

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

意味（3）

(astronomy, photography) 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.

This telescope has a 100 cm aperture.

意味（4）

(space flight, 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.

意味（5）

(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.