| 摘要 |
PURPOSE:To test the polarity identification mark positively by a method wherein a control circuit, which determines the direction of the test current by a light signal of at least two sensors which detect the polarity identification mark, and a signal circuit, which produces a discrimination signal between an article of good quality and an article of poor quality according to the direction of the test current and the polarity identification mark, are provided. CONSTITUTION:A polarity identification mark 3 is applied to a cathode side of a resin molded part 2 of a semiconductor element 1. So the light input of the reflected light to an optical sensor 41 is different from that to an optical sensor 42 and the side to which the polarity identification mark is applied is electrically identified by a light signal identifying circuit 5. Then, current i is applied to an anode side (a) by a current application control circuit 6 and as the polarity agrees with the identification mark 3 the specified current flows and the article is judged to be of good quality. On the other hand, when the polarity identification mark 3 is to the side of the optical sensor 41, the current is applied from the cathode side (b) to the anode side (a) by the control circuit 6. While, the direction of the current is reverse to the direction of the rectification of the semiconductor element 1, the current does not flow and the article is judged to be of inferior quality. |
