Apparatus for and method of controlling toner density

A toner density controlling method comprising:

• controlling a toner density by calculating a toner supply amount controlling value in accordance with a toner density set-up value and a toner density detection value by a toner sensor, wherein the controlling value is calculated by changing a toner supply amount controlling value operational constant in response to an amount of toner corresponding to printing data.

A toner density controlling method in an image forming apparatus having a toner supply amount controlling unit, a developing unit, the method comprising:

• generating a toner supply amount controlling value in accordance with printing data:
• and
• controlling the toner supply amount controlling unit to supply toner to the developing unit in response to the toner supply amount controlling value.

A toner density controlling apparatus having a toner supply amount controlling unit in an image forming apparatus, comprising:

• a memory storing an operational constant corresponding to an amount of dots forming an image representing printing data;
• and
• a controller controlling the toner supply amount controlling unit in accordance with the operational constant.