摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an exposure device that scans with a plurality of beams, that is large in size to be usable for a high-speed color printer device, and that has high degree of freedom in an image forming section. <P>SOLUTION: The exposure device 1 includes an imaging system 9 constituted of three first to third glass-made imaging lenses 23, 25 and 27 having Abbes numberνof≥60,≤28 and≤65, respectively, and laser beams L (Y, M, C and B) passing through the respective lenses form their optical paths to cross one another in the rotating axis direction of the polygon mirror of a deflector 5 between the polygon mirror and the first imaging lens 23, consequently, the machining cost is reduced, and the degree of freedom in the optical path related to the shape required as the image forming section is enhanced, and a variation in beam diameter of the laser beam at the imaging position and a variation in the imaging position are reduced. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |