JPS5567765A - Exposure device - Google Patents

Abstract

PURPOSE: To provide the construction suited for high speed copying by providing a stationary light source which gives condensed luminous flux to the same plane as the original, plural scanning mirrors which are placed perpendicularly to the original plane and are relatively movable and a movable lens at the intermediate of the original face and photoreceptor.

CONSTITUTION: A stationary light source 3 is so constituted that its luminous flux is reflected by, e.g., scanning mirrors 4, 4' and condenses at the same angle to the original face 2. The scanning mirrors 4, 4' are placed perpendicularly to the original face 2 and reciprocate parallel to the origianl face 2 respectively from the positions of the solid lines up to the positions of the alternate- long-and-two-short-dashes-line positions. A lens 5 moves at the same speed as the sum of the moving speeds of the scanning mirrors 4, 4' and in the same direction as the scanning light of the original face 2 and therefore the light out from the stationary light source 3 reflects on the scanning mirrors 4, 4' and original face 2 and form the original images in the same position on a photoreceptor 6 by the foregoing lens 5. The moving distance of the scanning mirror is about 1/4 the length of the original face and therefore the scanning mirror moving speed becomes 1/4 the speed of the scanning light of the original face. Hence, the moving mass of the mirrors or the like becomes small and the construction suited for high speed copying may be made.

COPYRIGHT: (C)1980,JPO&Japio