Image Number 14 for United States Patent #6462879.
The present invention relates to an optical writing device and an image forming apparatus and method in which the optical writing device is provided. In the optical writing device of the invention, a light source array has an array of light sources emitting a plurality of light beams. A focusing lens array has a row of focusing lens elements focusing the light beams from the light source array onto a surface of a photosensitive medium, the focusing lens elements being arrayed in an array direction, each focusing lens element having a visual field radius X in the array direction and a diameter D in the array direction. The focusing lens array is configured to satisfy the condition: m>2.0 where m is an overlap ratio of each of the focusing lens elements defined by the equation m=X/D.