出典:Wikipedia
出典:『Wikipedia』 (2010/08/24 22:16 UTC 版)
The globe effect, sometimes called the rolling ball effect or the spinning globe effect, is an optical phenomenon that occurs with visual optical instruments, in particular binoculars and telescopes, that are designed to be free of distortion. When these instruments are panned, the moving image appears to roll over a curved, convex surface. In 1949, Horst Koehler at Zeiss (Jena) suggested adding some pincushion distortion to the optical design to eliminate the globe effect. August Sonnefeld conducted experiments with volunteers, which supported the claim that a supplementary distortion could improve the imaging of visual optical instruments. Since that time, most binocular manufacturers have followed Zeiss's example and added pincushion distortion to their optical design.