Image forming apparatus for forming an image on an image bearing member

An apparatus for use in forming an image corresponding to digital image data and supplied from a host computer on an image bearing member, said apparatus comprising:

• means for receiving digital image data to be formed and supplied from said host computer;
• means for estimating the amount of toner to be attached to said image bearing member in accordance with the digital image data received by said receiving means;
• means for charging said image bearing member;
• means for exposing a light beam on said image bearing member so as to form a latent image on said charged image bearing member corresponding to digital image data to be formed and supplied from said host computer;
• means for developing the latent image formed on said image bearing member with a developing agent including toner;
• means for detecting the amount of toner attached to said image bearing member by said developing means;
• and
• means for controlling said charging means, said exposing means and said developing means with the amount of toner detected by said detecting means and the amount of toner by said estimating means so as to stabilize the image density changes of the image formed on said image bearing member.

An apparatus for use in forming an image on an image bearing member the image corresponding to digital image data supplied from a host computer, said apparatus comprising:

• means for receiving digital image data to be formed and supplied from said host computer;
• means for estimating the amount of toner to be attached to said image bearing member in accordance with the digital image data received by said receiving means;
• means for charging said image bearing member;
• means for exposing a light beam on said image bearing member so as to form a latent image on said charged image bearing member corresponding to digital image data to be formed and supplied from said host computer;
• means for developing the latent image formed on said image bearing member with a developing agent including toner;
• means for detecting the amount of toner attached to said image bearing member by said developing means;
• means for applying a grid bias voltage to said charging means;
• means for applying a developing bias voltage to said developing means;
• and
• means for controlling said charging means, said exposing means and said developing means by changing at least one of the grid bias voltage applied by said grid bias voltage applying means, the developing bias voltage applied by said developing bias voltage applying means, the exposure amount of the light beam exposed by said exposing means, the pulse width of the light beam exposed by said exposing means, and the ratio of toner included in said developing agent in accordance with the result of comparing the amount of toner detected by said detecting means and the amount of toner estimated by said estimating means.

An apparatus for use in forming an image corresponding to digital image data supplied from a host computer on an image bearing member, said apparatus comprising:

• means for receiving digital image data to be formed and supplied from said host computer;
• means for estimating the amount of toner to be attached to said image bearing member in accordance with the digital image data received by said receiving means;
• means for forming an image on the image bearing member, said image corresponding to digital image data to be formed and supplied from said host computer with a developing agent including toner under a predetermined image forming condition;
• means for detecting the amount of toner attached to said image bearing member by said forming means;
• comparing means for comparing the amount of toner detected by said detecting means and the amount of toner estimated by said estimating means;
• identifying means for detecting the frequency distribution of the image density changes with respect to a high-density portion and a low-density portion of the digital image data in accordance with each comparison result of said comparing means and identifying the trend of the image density changes;
• and
• control means for setting said image forming condition in accordance with the identified trend of the image density changes with respect to the high-density portion and the low-density portion and performing the image forming operation of said forming means under said set image forming condition so as to stabilize image density changes of the image formed on said image bearing member.

A method for use in forming an image on an image bearing member, the image corresponding to digital image data supplied from a host computer, said method comprising the steps of:

• receiving digital image data to be formed supplied from said host computer;
• estimating the amount of toner to be attached to said image bearing member in accordance with the received digital image data;
• forming an image on said image bearing member, said image corresponding to digital image data to be formed supplied from said host computer with a developing agent including toner under a predetermined image forming condition;
• detecting the amount of toner attached to said image bearing member;
• setting said image forming condition in accordance with the detected amount of toner and the estimated amount of toner;
• and
• performing the image forming operation of said forming means under said set image forming condition so as to stabilize image density changes of the image formed on said image bearing member.