| 摘要 |
<p>The pre-polygon scanning path length of a raster output scanning system is reduced by replacing a required cylinder lens, or lenses, with two cylindrical mirrors (30,32). One mirror with a negative, concave surface and a second positive cylindrical mirror. The first mirror (30) directs the light beam to the second mirror (32). The second mirror (32) directs the light onto the facets (18A) of a rotating polygon to form a focused beam in the vertical axis of the polygon. The function of the two cylindrical mirrors (30,32) is to act as a telephoto lens to properly focus the image of the laser at the polygon facet while reducing the total pre-polygon path length.</p> |
