| 摘要 |
PROBLEM TO BE SOLVED: To provide a developing device that forms a high quality developed image regardless of a remaining quantity of developer. SOLUTION: When the quantity of remaining toner 102 is equal to or below a predetermined value, a DC component of a development bias is decreased. Herein, a DC component of 500 V in an ordinary mode is switched to a DC component of 470 V in a post-durability mode. In both the ordinary mode and the post-durability mode, a peak voltage of an AC component is 1,600 V, and frequency of the AC component is 2,000 Hz. |
