| 释义 |
f-number
f-num·ber (ĕf′nŭm′bər)n. The ratio of the focal length of a lens or lens system to the effective diameter of its aperture. Also called f-stop.
[f(ocal length) + number.]f-number or f numbern (Photography) photog the numerical value of the relative aperture. If the relative aperture is f8, 8 is the f-number and indicates that the focal length of the lens is 8 times the size of the lens aperture. See also T-numberf-number (ˈɛfˌnʌm bər)
n. a number corresponding to the ratio of the focal length to the diameter of a lens system, esp. a camera lens. Symbol: f/ [1890–95] Translationsf-number
f-number, f number Photog the numerical value of the relative aperture. If the relative aperture is f8, 8 is the f-number and indicates that the focal length of the lens is 8 times the size of the lens aperture MedicalSeef number |