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 results were correlated in term of j and f as a function of Reynolds number and the geometrical parameters of heat exchangers by multiple linear regression technique.
  通过多元线性回归法将实验数据整理为以雷诺数和换热器几何参数为自变量的j和f关联式。
• 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（？）
• If diffractive efficiency is not considered, the numerical results show that larger f number microlens has smaller divergence angle.
  同时，如果不考虑微透镜的衍射效率，当球面折射微透镜的F数越大，高斯光束经过准直变换后的远场发散角越小。
• The ray tracing method and vectorial Stratton Chu diffraction Integration are applied in the analysis of the imaging performance over the focal planes of hyperbolic lens and reverse microscope lens system with small F number.
  采用射线追迹结合StrattonChu矢量衍射积分公式的方法分析计算了小F数双曲透镜和倒置显微镜的焦面成像特性。
• The F number standard for concrete floor developed by american concrete Institute and Canadian Standards Association is superior to the standard known as the gep under a straight edge. This paper briefly introduces its significance and application metod on site.
  介绍了美国混凝土学会和加拿大标准学会的F数标准，以及使用该混凝土地面平整度和水平度标准的现实意义和现场测量方法。
• 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。
• 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 degree of a face f in G ( written r ( f)) is the number of edges of G incident with f, each cut edges counting as two edges.
  一个面所关联的边的个数（割边要计算两次），被称为面的度，用r（f）表示。
• Research on Fabrication and Optical Performance Testing of Silicon Microlenses Array with Large F/ Number
  大F数硅微透镜阵列的制作及光学性能测试研究