| 摘要 |
PURPOSE:To improve the accuracy of package tests by subjecting the portion other than the test area to mask treatment so that the signal output from the unnecessary portion may be eliminated. CONSTITUTION:A mask 21 is formed with a slot-shaped aperture or transparent portion 23 corresponding to a pocket 22 for receiving each product. On the other hand, the mask 21 itself is made of such a suitable material as can prevent the signals from the undesired portion from passing therethrough. The mask 21 is arranged between the sheet 1 and an image sensor 4 above a conveyor 2 by which the PTP sheet is conveyed. As a result, the sensor 4 is shielded from the light from above the sheet so that only the light from the product or the test piece can come. On the other hand, the testing mask at the sheet portion has its transparent and shielding portions reversed from those of the mask 21. By masking the portion other than the test area to block the generation of the undesired signals, it is possible to improve the testing accuracy. |
