Optics.
the magnification produced by a telescope or microscope such that the diameter of the exit pupil of the instrument is equal to the diameter of the pupil of the eye.
Optics.
the magnification produced by a telescope or microscope such that the diameter of the exit pupil of the instrument is equal to the diameter of the pupil of the eye.
Random House Webster's Unabridged English dictionary. Полный английский словарь Вебстер - Random House . 2012