| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus and an image forming method for forming a high-quality image by surely restraining a density irregularity while surely preventing discharge from occurring. <P>SOLUTION: By applying alternating voltage having an amplitude Vpp<SB>-</SB>(m-1) to a developing roller 31, a patch image is formed, and the optical density D(m-1) of the patch image is detected, and temporarily stored in a memory. Then, an amplitude Vpp<SB>-</SB>m different from the amplitude Vpp<SB>-</SB>(m-1) is obtained based on discharge limit characteristic (discharge limit line), and the patch image is formed by applying the alternating voltage having the amplitude Vpp<SB>-</SB>m, and the optical density Dm of the patch image is detected. When a density difference (=|Dm-D(m-1)|) made before and after changing the amplitude is equal to or under a specified value, the amplitude Vpp<SB>-</SB>(m-1) on a low amplitude side is decided as optimum amplitude. <P>COPYRIGHT: (C)2003,JPO |
