Fresnel number

短语

词形变化

Fresnel numbers 复数 Fresnel numbers

释义与例句

n.
  1. 1.

    A dimensionless quantity (denoted F), such that for an electromagnetic wave passing through an aperture and hitting a screen, F=(a²)/(Lλ) where a is the characteristic size (e.g. radius) of the aperture, L is the distance of the screen from the aperture, and λ is the incident wavelength.

    工程 物理

词源

Named after the physicist Augustin-Jean Fresnel.

来源：wiktionary