PURPOSE: To always obtain a stable image quality by controlling the voltage applied by a first developing bias applying means based on a signal detecting an image of reference density after the reference density image corresponding to the density of a first toner image is formed prior to the formation of a first latent image.
CONSTITUTION: Just after an image forming device operates, a reference picture forming means 14 forms a reference latent image pattern on a latent image carrier, and simultaneously the image is developed and is detected by a reference density image detecting means 26. The signal detected by the reference density image detecting means 26 is transmitted to a developing bias control means CPU, which compares and operates the detecting signal and a previously measured reference value to determine a prescribed, applied bias voltage value. According to the applied bias voltage value, the developing bias applying means applies a developing bias voltage selected by a first developing means 14 to develop a first toner image. Thus, a stable image quality can be obtained under any environments.
| JP2005055750 | IMAGE FORMING APPARATUS |
| JP5322899 | Image forming device |
| JP4095637 | Image forming device |
MARUYAMA KAZUO
SAIKAWA TAKESHI
ADACHI KOJI
FURUYA NOBUMASA
