Meaning of curtain shutter

cur'tain shut"ter

Pronunciation: [key]
— Photog. Photog.
  1. a focal-plane shutter consisting of a curtain on two rollers, moved at a constant speed past the lens opening so as to expose the film to one of several slots in the curtain, the width of which determines the length of exposure. Also called
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.