| 摘要 |
PROBLEM TO BE SOLVED: To obtain a scanning optical device whose constitution is highly precise and also is simple. SOLUTION: A luminous flux emitted from a light source means 1 is deflected by a deflecting means 5, and the luminous flux deflected by the deflecting means 5 is guided to a surface to be scanned 7 by a scanning optical means 6, so that the surface to be scanned 7 is optically scanned. In this case, the scanning optical means 6 possesses a first optical element 6a which does not have power caused by refraction and a second optical element 6b consisting of an anamorphic lens having different positive power caused by the refraction in a horizontal scanning direction and a vertical scanning direction, and a diffraction grating 8 having the positive power caused by diffraction is formed on at least one surface of the first optical element 6a. |
