N-COUNT
（照相机的）光圈，孔径
In photography, the aperture of a camera is the size of the hole through which light passes to reach the film.
例句
Use a small aperture and position the camera carefully...
用小光圈，仔细调整相机位置。
The camera has a 32mm lens with a maximum aperture of f/4.5 and a fixed shutter speed of 1/100sec.
这架相机有一个32毫米的镜头，最大孔径为f/4.5，固定快门速度为1/100秒。