PURPOSE: To protect a recording medium against contamination by providing exposure inhibition means to inhibit individual exposures to a recording medium and a means to detect a position for commencement of subscan with individual light sources on a medium to be recorded and drive the individual exposure inhibition means for controlling exposure to the recording medium.
CONSTITUTION: The first sensor S1Wthe fourth sensor S4 for detection of an available stack of paper 20 are arranged along a transport path 21 for paper 20 to be transported synchronized the rotation of a photosensitive drum 1. When the tip of the paper is detected by the second sensor S2, image formation is initiated by the first exposure, and when the rear end of the paper is detected by the second sensor S2, image formation by the first exposure is inhibited. In addition, when the tip of the paper is detected by the fourth sensor S4, image formation by the second exposure is begun, and when the rear end of the paper is detected by the third sensor S3, image formation by the second exposure is inhibited. In this manner, image formation is controlled; it is possible to prevent contamination of the tip or rear end of the paper by toner for latent image formation, subsequent fouling of a recording medium and, in turn, the induction of causes of jamming near a fixing means such as a transfer device.
SERIZAWA YOJI
SAKAKI SHIGEHIRO
USHIO YUKIHIDE
SETO KAORU
