IMAGE FORMING APPARATUS

PROBLEM TO BE SOLVED: To prevent an electrostatic latent image not depending on image information from being formed on a photoreceptor. SOLUTION: An image forming apparatus includes: a photoreceptor; an electrifying device electrifying the photoreceptor; a semiconductor laser light source; and a driving device including: an optical output detection part connected to the semiconductor laser light source and detecting the optical output of the semiconductor laser light source; a comparison part comparing the output signal of the optical output detection part with a predetermined reference signal; a bias current supply part supplying a constant bias current to the semiconductor laser light source; a modulated current supply part supplying a modulated current modulated according to image density to the semiconductor laser light source; and a control part controlling the modulated current supply part and the bias current supply part and forms the electrostatic latent image corresponding to the image information on the photoreceptor by an optical scanning device. The modulated current supply part supplies a preheating current to the semiconductor laser light source, in an area where an image is not formed on the photoreceptor with light emitted from the semiconductor laser light source. COPYRIGHT: (C)2010,JPO&INPIT