| 摘要 |
PROBLEM TO BE SOLVED: To provide a device and method for image forming by which higher- resolution images can be formed, while the gradation of the image is maintained. SOLUTION: Triangular wave generating sections 302 and 303 respectively generate first and second reference signals of triangular waves, having a phase difference of 180 deg. between them. Comparators 304 and 305 respectively perform pulse width modulation on analog image signals, based on the first and second reference signals. At the time of forming a first Bk(black) image, the Bk image is formed by driving a laser diode 308, while selecting the output of the comparator 304. At the time of forming a second Bk image, on the other hand, the Bk image is formed by driving the diode 308 while selecting the output of the other comparator 305. The first and second Bk images are composited on a recording paper. |
