f number

英 [ˈef nʌmbə(r)]

美 [ˈef nʌmbər]

焦距值；光圈数

英英释义

noun

• the ratio of the focal length to the diameter of a (camera) lens system
  Synonym:focal ratiostop numberspeed

双语例句

• Investigation on space optical system of high F number and high resolution
  大F数高分辨率空间望远镜光学系统
• The F number was 1. The lens group consisted of 3 elements.
  设计的物镜F数为1，三片式结构。
• The optical performance of small F number diffractive microlens arrays little voice
  小F数衍射微透镜阵列光学性能研究
• The author presents a method of calculating the error of location and analyses the relationship between the error of location and the frequency difference of double-frequency grating ( or the amount of shear) and F number of the system.
  文中提出了计算定焦误差的方法，分析了定焦误差与双频光栅的频率差（或剪切量）及系统的F数之间的关系。
• Papers during the theoretical analysis, but also cited a number of companies in the procurement of F found in a number of practical issues and give the corresponding solution to the problem.
  论文在进行理论分析的同时，也列举了一些F公司在采购工作中发现的一些实际问题并给出相应解决问题的办法。
• The results show that under increasing pressure the band occupation numbers change, with s and p electron number gradually transferring to d and f electron number.
  结果表明，随着压强的增加，能带电子占据数发生变化，s分波和P分波电荷逐步向d分波和f分波电荷转移；电声矩阵元中p（？）
• The matric characteristics and convergences on F-number space
  F数空间的度量特征及收敛性
• In the past design, under the conditions of larger discharge and energy dissipation, flow cavitation number σ f larger than incipient cavitation number σ I of the flood tunnel must be satisfied to avoid cavitation in it.
  在以往的设计中，在满足较大的泄量和消能量条件下，通常泄洪洞还要满足σf＞σi，以免发生空化空蚀。
• F any product on which the serial number has been removed, defaced or modified.
  任何产品上的序列号已被删除，涂改或修改。
• Improving the Fill Factor and F Number of Refractive Microlens Array by Reducing Developing Time
  通过缩短显影时间提高微透镜阵列的填充因子与F数