O Make a photographic noun

[guāng quān]

Aperture

Aperture is a device used to control the amount of light that passes through the lens and enters the photosensitive surface of the fuselage. It usually It's in the shot. We use f-number to express aperture size. For a lens that has been manufactured, we cannot change the diameter of the lens at will, but we can control the amount of light passing through the lens by adding a polygonal or circular hole-shaped grating with variable area inside the lens. This device is called an aperture.