| 释义 |
Definition of Petzval in English: Petzvalnoun ˈpɛtsvɑːlˈpɛtsv(ə)l Optics Photography Used attributive with reference to various concepts related to a lens system designed by Petzval; specifically "Petzval condition"noun the condition for freedom from astigmatism of a compound lens, that the sum of the ratios of the power of each element to its refractive index be zero. "Petzval lens"noun a lens consisting of two widely spaced colour-corrected compound lenses whose negative elements are on the inner sides. "Petzval sum"noun a number representing the degree of curvature of the field of a compound lens, derived from the refractive indices and surface radii of its elements.
Origin Late 19th century; earliest use found in William de Wiveleslie Abney (1843–1920), civil servant and photographic scientist. From the name of József M. Petzval, Hungarian mathematician. Definition of Petzval in US English: Petzvalnoun Optics Photography Used attributive with reference to various concepts related to a lens system designed by Petzval; specifically "Petzval condition"noun the condition for freedom from astigmatism of a compound lens, that the sum of the ratios of the power of each element to its refractive index be zero. "Petzval lens"noun a lens consisting of two widely spaced colour-corrected compound lenses whose negative elements are on the inner sides. "Petzval sum"noun a number representing the degree of curvature of the field of a compound lens, derived from the refractive indices and surface radii of its elements.
Origin Late 19th century; earliest use found in William de Wiveleslie Abney (1843–1920), civil servant and photographic scientist. From the name of József M. Petzval, Hungarian mathematician. |