Electrophotographic apparatus for depositing developer only on the image area of the image bearing member

An electrophotographic apparatus comprising:

• developing means for depositing, in a first mode of operation of said apparatus, a developer on the dark potential portion of a latent image formed on an image bearing means which has not been exposed to light, and for depositing, in a second mode of operation of said apparatus, another or the same developer on a light potential area of the latent image on the image bearing means which is exposed to light;
• exposure means for exposing a non-image forming area of the image bearing means in both of said first mode and said second mode;
• and
• bias voltage applying means for applying a bias voltage to said developing means,
• wherein said bias voltage applying means applies a bias voltage for preventing deposition of the developer in the non-image-forming area in both of said first mode and said second mode.

An electrophotographic apparatus, comprising;

• an image bearing member;
• charging means for uniformly charging said image bearing member;
• developing means for developing a latent image formed on said image bearing member by a developer charged to a polarity, the same as the polarity to which said image bearing member is charged;
• bias voltage applying means for applying a bias voltage to said developing means;
• first control means for changing the bias voltage depending on whether said bias voltage is used for controlling the operation of said developing means with respect to the image forming area or the non-image-forming area;
• exposure means for exposing the non-image forming area of said image-bearing member;
• and
• second control means for controlling said exposure means, wherein said first control means changes the bias voltage at a position on said image bearing member which corresponds to a position thereof where said second control means turns off said exposure means.

An image forming apparatus, comprising:

• an image bearing member;
• means for forming a latent image having a high potential portion and a low potential portion on said image bearing member;
• means for developing the latent image by depositing a developer on the low potential portion of the latent image;
• means for electrically discharging a non-image area of said image bearing member;
• and
• control means for controlling said developing means to prevent the developer from being deposited on the non-image area of said image bearing member.