OPTICAL WRITING HEAD AND IMAGE FORMING APPARATUS USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide an optical writing head and an image forming apparatus wherein a clear image is obtained even when the printing is performed by a high recording density of around 1200 dpi, a transmission rate of a light quantity is high, a load to a light source array emission quantity or a sensitivity of a photosensitive body is reduced, the apparatus can be reduced in size, and partial stripe like variation hardly occurs. SOLUTION: An LED print head writes optical information from an LED array on a photosensitive material of a photosensitive drum by two rows of refractive index profile type rod lens arrays. An opening angleθof each of lens elements forming the rod lens array is set in a range of about 14 deg.-18 deg.. It is possible to obtain a resolution of not less than 50% of one necessary for printing at a recording density of 1200 dpi and a clear image without a stripe can be obtained even in the printing at the above recording density.