| 摘要 |
PURPOSE:To always obtain a uniform and excellent picture data by providing a reflecting plate having a uniform density in the main scanning direction of picture information and measuring the luminous quantity change from the luminous quantity information obtained based on the reflected light from the reflecting plate before the picture information is read. CONSTITUTION:In turning on a read start button, a timer is started, a fluorescent lamp is lighted, the luminous quantity information S1, S2 and S3 as to three positions of the fluorescent lamp, right, middle and left end are stored once in a latch circuit 11 and reference values V1, V2 and V3 decided in advance are compared by a CPU 12. As a result, when the values are a reference value or over, it is discriminated that the luminous quantity is normal, an optical scanning unit is driven to start the read. When the detected luminous quantity information S1, S2 and S3 are the reference values V1, V2 and V3 or below and its state is consecutive for a prescribed time or over on the other hand, it is discriminated that the luminous quantity required for the read is deficient to warn light source fault and the read operation is stopped.
|
