| 摘要 |
PURPOSE:To stabilize an illumination of an original by controlling a generation of a high frequency current basing on a detecting output of a temperature detector. CONSTITUTION:Even in a period in which a transmission request signal (a) does not exist, a control signal (b) depends on an output signal (c) of a controlling circuit 14, and a tube wall temperature (t) of a fluorescent tube 12 is held in a prescribed range. The transmission request signal (a) is generated, the control signal (b) becomes effective irrespective of the output signal (c), and a high frequency generating circuit 11 generates a high frequency current, therefore, even if it is generated in a state that the fluorescent lamp 12 is turned off, a resolution drop of a read signal of an original reading part does not occur. |
