| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus in which the miniaturization of an optical scanner and the space saving in the depth and height direction of a housing can be realized. <P>SOLUTION: The optical scanner 20 arranged inside the image forming apparatus 10 is provided with a polygon mirror 54 for deflecting a laser beam. Also, an fθ-lens 60 for imaging the laser beam to a photoreceptor drum 12 and a turn back mirror 62 for reflecting the laser beam are disposed on the downstream side in the progression direction of the laser beam. At this time, the distance L between the end surface of the fθ-lens 60 and the turn back mirror 62 is set at 8 mmL≤L≤25 mm and the turn back angle Θ of the laser beam by the turn back mirror 62 is set at 25°≤Θ≤45°. Further, the fθ-lens 60, the turn back mirror 62 and the photoreceptor drum 12 are so arranged that the relation between L and Θ satisfies 8 mm≤LtanΘ≤12 mm. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
