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
双语例句
- Based on the hydraulically and thermally developing flows, the flow and temperature fields, Nu, f and field synergy number Fc are obtained for different Re and wall temperatures.
模拟以通道入口段的流动和换热为对象，得到了不同Re和不同壁温下的流场和温度场，对流换热的Nu和阻力系数，以及场协同数Fc。 - The effective focal length and back working distance of the system are respectively 100 mm and 113 mm, while the F number is 2.0.The system which has only three lenses contains two negative germanium lenses and one positive zinc selenide lens.
该系统全视场为14°，有效焦距为100mm，后工作距为113mm，F/2.0.系统采用锗和硒化锌两种材料，为三片镜结构。 - 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 - The matric characteristics and convergences on F-number space
F数空间的度量特征及收敛性 - 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 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 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 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 - This paper analyses colour subcarrier quantization noise in PCM coding of complete television singal. The relationship between quantization noise and sampling frequency ( f s) as well as quantizing bit number ( n) is discussed.
分析了全电视信号PCM编码色度副载波量化噪声，并讨论了量化噪声与取样频率fs和量化比特数n的关系。 - 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。