| 摘要 |
PURPOSE:To prevent the erroneous detection of defective printing and to accurately perform the inspection of the defect of a printed matter by respectively comparing an output signal from a 1st waveform processing circuit with an output signal from a 2nd waveform processing circuit and one-line delay circuit. CONSTITUTION:The output signal from the 1st waveform processing circuit 21A is respectively compared with the output signals from the 2nd waveform processing circuit 21B and the one-line delay circuit 7A. When the output signal from the circuit 21A does not coincide with the output signals from the circuit 21B and the circuit 7A every section of an image pickup line, a defective printing detection signal is generated for the section. At such a time, when the output signal from the circuit 21A coincides with at least one of the output signals from the circuit 21B and the circuit 7A, the defective printing signal is not generated for the section. Therefore, the erroneous detection of the defective printing caused by the positional deviation of two lines of printing patterns to be inspected in the moving direction of a printing paper 1 and an error in adjusting the positions of 1st and 2nd line sensor cameras 2A and 2B is prevented. Then, the inspection of the defect of the printed matter, etc., for which an inexpensive paper is used is accurately performed. |
