Patent ID: 8831449

Claim:
An image forming apparatus comprising: an image carrier; a developing device; a transfer device; a fixing device, wherein an electrostatic latent image formed on the image carrier is rendered visible as a toner image by depositing toner thereon by the developing device and the toner image is transferred by the transfer device and fixed onto a recording medium by the fixing device and output; a density fluctuation meter including a rotary position detector to detect a position of the image carrier in a rotation direction; a density fluctuation detector to detect the density fluctuation of the image carrier in the rotation direction; and a density fluctuation storage to store the density fluctuation detected by the density fluctuation detector; a density fluctuation extractor unit, including: a density fluctuation extractor to extract a density fluctuation of the image carrier rotary cycle; an analyzer to extract an amplitude and a phase of an n-th component of the density fluctuation when the rotary cycle of the image carrier is set to 1 based on the rotary position detection signal of the image carrier in the rotation direction from the extracted density fluctuation of the image carrier rotary cycle; a density fluctuation calculator to calculate a density fluctuation profile of one cycle of the image carrier from the n-th component of the amplitude and the phase of the density fluctuation; and a density fluctuation storage to store the calculated density fluctuation; and a control table generator unit to generate a control table including: a control table generator to calculate a voltage to be applied to the developing device based on the density fluctuation data of one cycle of the image carrier stored in the storage; and a control table storage to store the generated control table, the voltage to be applied to the developing device being controlled and the toner image output based on the control table stored in the control table storage, wherein the control table is created by using only the components below the n-th higher harmonics being below a previously set phase error when the basic rotational cycle of the image carrier is set to 1.