| 摘要 |
PURPOSE:To always match the image forming point of a laser beam for scanning on an image surface with a simple means by arranging one end side of an optical fiber bundle composed of numerous optical fibers along a locus drawn by the image forming point of a laser beam in accordance with the turn of a deflector and, at the same time, facing the other end side to the image surface. CONSTITUTION:A laser beam Lb emitted from a laser light source forms an image in a space after passing through a focusing lens 1 and polygon mirror 2. The image forming point of the laser beam Lb draws a circular arc-like locus 4 in accordance with the movement of a deflecting surface following the rotation of the mirror 2. Numerous optical fibers 6 are arranged in a single or plural rows, with their one ends being trues up to the focal surface of the laser beam Lb presumed along the locus 4. The other end side of the optical fiber bundle 60 composed of the fibers 6 is closely faced to a photosensitive surface 30 at a fixed interval in a trued up state. Therefore, the focal surface of the laser beam Lb for scanning can easily be made coincident with the photosensitive surface which is the image surface of the beam Lb with a relatively small space even when the scanning angle of the beam Lb is large. |
