| 摘要 |
PURPOSE:To certainly perform inspection, by setting a printing picture pattern itself as a detecting mark and detecting the same at every color component by a R.G.B. sensor utilizing an optical fiber. CONSTITUTION:A R.G.B. sensor 22 uses a color separating filter to separate inputted light into three red, green and blue components and converts said components to electric signals corresponding to the densities of respective color components. These electric signals are amplified by a sensor amplifiers 23 and converted to digital values by an A/D converter 16 to be inputted to a processing unit 5. When a measured value shifted from a boundary value different in a preset predetermined ratio is inputted, an alarm is issued by a display device 6 and an alarm device 17 and the number of inferior sheets are displayed on the display device 6 each time. The quality judgment of the measured value is performed by comparing the measured value of printed matter flowing continuously or intermittently with that of the first one and that of the next. By this method, the discrimination capacity of top and bottom reverse/back whiteness is markedly enhanced. |
