| 摘要 |
PURPOSE:To obtain the normal light beam with a simple operation by correcting the focal position of the light beam according to the deviation of the optical equiv. position of a detecting means and a photosensitive body after the focal position adjustment of the light beam on the photosensitive body detecting the positional relation between the optical equiv. position of the detecting means and the photosensitive body. CONSTITUTION:The adjustment of a collimator lens system 3 by a focus adjusting means 4 is started and while the lens system 3 is successively intermittently driven in a prescribed section, the detection signal outputted from a solid-state image pickup element 8 is monitored and the intermittent moving quantity of the lens system 3 is displayed as the focal position of the light beam on a body operating section 2. The deviation in the disposition of the element 8 and the photosensitive drum 9 is announced as the intermittent moving quantity of the lens system 3 in parallel therewith. The relative correction quantity of both of the correction quantity in the present deviation of the focal position of the present light beam and the optical equiv. position of the element 8 and the photosensitive drum 9 are announced in this way. An AF control section 10 corrects the correcting movement of the lens system 3 by the deviation in the disposition and the intermittent moving quantity so as to attain the normal light beam when the data on the deviation of the disposition is inputted. |
