| 摘要 |
A scanning optical apparatus comprises a light source means, deflector means (5) for deflecting a light beam emitted from the light source means in a main scan direction of the scanning optical apparatus, and a first optical element for receiving the light beam emitted from the light source means and guiding the light beam on a deflection surface of the deflector means (5). A second optical element (6) receives the light beam deflected by the deflector means (5) to form a spot image on a scanned surface (8). A Gaussian imaging plane (82) in a sub scan direction of the scanning optical apparatus is positioned between the deflector means (5) and the scanned surface (8), wherein the positional difference between the Gaussian imaging plane (82) in the sub scan direction and the scanned surface (8) is the largest at the center of the second optical element (6) and wherein this difference becomes smaller from the center of the second optical element (6) toward the periphery of the second optical element. <IMAGE> |
