| 摘要 |
PROBLEM TO BE SOLVED: To provide an ion detector excellent in durability which can measure the number of high speed heavy ions, energy, and the like, stably. SOLUTION: When a high speed heavy ion I impinges on the metal deposition film 1 of an ion detector 10, thermal expansion takes place locally in the metal deposition film 1 along the trajectory of the high speed heavy ion I to generate a thermal expansion pulse in the region 5. A thermal stress pulse generated by the thermal expansion pulse in the metal deposition film 1 is applied to the surface of a piezoelectric element 2 to generate a compressive impact 6 and a voltage pulse proportional to the magnitude thereof is induced in the piezoelectric element 2. The voltage pulse is inputted through terminals 4a, 4b and a pulse amplifier to a pulse circuit and the incident high speed heavy ion I is detected one by one as a pulse. Energy of the high speed heavy ion I is measured from a previously calibrated relationship between the magnitude of voltage pulse and the ion energy.
|
