| 摘要 |
<p>PURPOSE:To enhance the quality of a printing image by providing a point source array in which a plurality of point sources are arranged in a matrix state, providing dot enlarging means for enlarging a light irradiated from the point source, and providing optical image contracting means for contracting an irradiated whole optical image. CONSTITUTION:A light irradiated corresponding to the dots of a printing image is passed through the slit 19 of a matrix 15 to remove its scattered component to be introduced into a lens array 16, and enlarged by microlenses 20. The enlarged dot matrixlike optical image is contracted by projection lens 17 to be focused on a photosensitive drum, and printed in an electrophotographic type. Accordingly, in a column type printer 12, the pitch of an LED 18, the diameter of the slit 19, the variable magnifications, etc. of the microlens 20 and the projection lens 17 are determined on the basis of a desired printing size and dot density, thereby easily obtaining a high quality printer.</p> |
