| 摘要 |
<p>PROBLEM TO BE SOLVED: To realize at low cost the high speed formation of a half tone image that is more beautiful than before by arranging one unit, in which a light focusing element, an optical opening, a collimator part and a hologram element are arranged, in the form of an array in the same number as the number of pixels in a main scanning direction. SOLUTION: Write optical beams 22 are converged on a minute optical opening 23 by means of a light focusing element 21 constituted of a conical mirror or the like, with a micro optical spot formed. A light flux emitted from the opening 23 is made incident on a collimator part 24 arranged as necessary. The outgoing light from the opening 23 is made the parallel light flux by the collimator part 24, with the light flux made incident on a hologram element 25 which has a function for splitting and radiating this light flux in plural directions and a function for converging each light flux generally on the same plane. A photosensing surface of an image recording medium 26 is provided on the plane on which the light flux groups emitted from the hologram element 25 each focus. Incidentally, the collimator part 24 is constituted of a convex lens array or the like.</p> |
