X-RAY FOREIGN MATER DETECTOR AND METHOD OF DETECTING DEFECTIVE IN THE DETECTOR

摘要

PROBLEM TO BE SOLVED: To improve the reliability of a detector by accurately detecting a defective. SOLUTION: A mask region setting part 17a of a deficiency detecting part 17 sets a mask region M for deficiency detection on the basis of a storage body T of an inspected object W. An inspected object extracting part 17b extracts an extracted image A of only the inspected object W from the data of the amount of X-ray transmission outputted from an X-ray detector 3. When the rate of the extracted image A of the inspected object W included in the mask region M is lower than a prescribed value, a deficiency determining part 17c determines the defective being accommodated in the storage body without the inspected object. Even when only a part of the extracted image A is included in the mask region M due to the movement of the inspected object W in the storage body T, erroneous detection of deficiency by the determination using the rate can be prevented to attain the accurate detection of the defective.