| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus constituted so that the drive of a part to be interlocked can be surely stopped when the abnormality occurs, and also, the number of components such as a signal conductor used only for an interlocking notice signal and a functional pin etc., is reduced, and then, the cost reduction can be attained. <P>SOLUTION: When a switch 493 is turned off, power supply from a power supply part 492 to a laser driving part 11 and a beam detecting part 12 is stopped. When the power supply to the beam detecting part 12 is stopped, a beam detecting signal is switched from a pulse state to a low-level state by a clamp diode 123 arranged on the poststage of an amplifier 122. The effect that the beam detecting signal is switched to the low-level state is detected by the signal detecting part 102 of a control part 10, then, the output of a video signal from a signal driver 101 is stopped. The number of signal lines can be reduced by using the existing beam detecting signal as the interlocking notice signal. <P>COPYRIGHT: (C)2004,JPO&NCIPI |
