Patent ID: 7358984

Claim:
An image forming apparatus comprising: an electrophotographic photoreceptor having a conductive substrate and a photosensitive layer provided on the conductive substrate; a charging unit that charges the electrophotographic photoreceptor; an exposure unit that exposes the charged electrophotographic photoreceptor to light thereby forming an electrostatic latent image; a developing unit that developes the electrostatic latent image with toner thereby forming a toner image; and a transfer unit that transfers the toner image from the electrophotographic photoreceptor to a transferred image-receiving medium, wherein said exposure unit is a multi beam exposure unit which has a surface emitting laser array and which carries out the electrostatic latent image formation by scanning the electrophotographic photoreceptor with eight or more light beams, wherein said electrophotographic photoreceptor gives a quantum efficiency of 0.3 or higher when the electrophotographic photoreceptor is charged to a charged potential absolute value of 500 V and then irradiated with a monochromatic light of the same wavelength as that of said light beams to decay the charged potential absolute value to 250 V, and wherein the light beams emitted by the exposure unit have a wavelength of 780 nm.