| 摘要 |
<p>The present invention relates to a high resolution exposing device for a printing plate printer using ultraviolet rays, comprising: multiple laser diodes to exit light of 400nm to 410nm, light fiber to waveguide the light exited from the laser diodes, and a lens unit to condense the exited light on an image surface to be printed through the light fiber. The lens unit includes first to eighth lens which are sequentially arranged in the direction to the image surface side from the light fiber, wherein the first lens has a double-sided convex spherical type and positive refractive power, the second lens has a double-sided concave spherical type and negative refractive power, the third lens has positive refractive power of a meniscus type having the convex image surface side, the fourth lens has negative refractive power of a meniscus type having the concave image surface side, the fifth lens has positive refractive power of a double-sided convex type, the sixth lens has positive refractive power of a double-sided convex type, a seventh lens has negative refractive power of a double-sided concave type, and the eighth lens has the convex surface facing the seventh lens and positive refractive power. The fourth lens and the fifth lens are bonded to each other, and the sixth lens and the seventh lens are bonded to each other. According to the present invention, the high resolution exposing device for a printing plate printer using ultraviolet rays can increase the opening number, have improved light condensing efficiency, and provide high resolution.</p> |
