Optical write-in head, image forming apparatus using the same, and method for inspecting the apparatus

摘要

An optical write-in head for obtaining a clear image even in printing at a relatively high recording density without generating strip-like irregularities in most cases. The optical write-in head applies light carrying image information to a photosensitive substance. The optical write-in head includes an array light source (23) having a plurality of dot light sources, each of which selectively emits the light corresponding to the image information, and a lens array (24) facing the array light source. The lens array (24) has a plurality of lens elements (25) which corresponds to the plurality of dot light sources respectively. An angular aperture &thetas; of each of the lens elements (25) is set in a range of about 14 DEG to 18 DEG .