| 摘要 |
PROBLEM TO BE SOLVED: To reduce effects of a sub emission band onto formation of a rod lens array, provide a constitution for preventing light of the sub emission band from reaching a development level, and obtain a high image quality in an LED printer head. SOLUTION: The LED printer head is comprised of an LED array arranged with a resolution pitch P of not smaller than 600 dpi to emit light in accordance with image signals, and a multi lens array for forming emission images of the LED array to a photoreceptor. An LED of the LED array has an emission spectrum primary emission band and another sub emission band of a peak level of not smaller than 0.01 at a photosensitive intensity ratio R to a primary emission spectrum. A difference D of best TCs at a primary and a sub peak wavelengths of the multi lens array is present at least by 0.15 mm or larger. The LED array and the multi lens array are optically adjusted so that the light of the primary emission band can obtain a predetermined image formation relationship on the predetermined photoreceptor. |
