| 摘要 |
PURPOSE:To enable the detection of the polarity and generation amount of an ion, by connecting an ion detection plate and earth to FET in a change-over possible state. CONSTITUTION:An ion detection plate 3 is connected to the gate of FET1 and earth 4 to a drain and the generation amount of a cation is detected through an amplifying transistor 3 and a meter 7. When switches 5, 6 are changed over to connect the detection plate to the drain of FET1 while connecting the earth 4 to the gate of FET1, the amount of an anion is detected similarly. |
