Image forming apparatus having a photosensitive drum rotatable at different speeds

An image forming apparatus which forms on a recording paper a visible image in accordance with image data, the forming being effected by using an electrophotographic method comprising:

• processing means, comprising a photosensitive drum on which a latent image is formed while the drum is being rotated at a predetermined rotational speed, for processing said image data so as to form said visible image;
• conveying means for conveying said recording paper to/from said processing means;
• driving means for driving said photosensitive drum and said conveying means;
• and
• controlling means for controlling said driving means so that said rotational speed of said photosensitive drum is changed based on a length of said visible image to be formed on said recording paper;
• wherein said driving means comprises a stepping motor, and said controlling means changes said rotational speed of said photosensitive drum by changing a cycle of an electric pulse supplied to said stepping motor;
• and
• wherein said photosensitive drum is rotated at a first rotational speed when said latent image is being formed thereon or at a second rotational speed faster than said first rotational speed, and wherein said controlling means changes said rotational speed of said photosensitive drum from said first rotational speed to said second rotational speed when a formation of said latent image corresponding to one page of said recording paper is complete.