| 摘要 |
PROBLEM TO BE SOLVED: To provide an ionization chamber capable of measuring radiation dose quickly and with high sensitivity without being influenced by an outside electric field even if its opening is not electrostatically shielded.SOLUTION: An ionization chamber 10 includes: a first electrode 13 which is placed in interior space 10s specified by a wall 11 and an opening 12 and to which predetermined voltage is applied; and a second electrode 14 for collecting and outputting electric charge corresponding to radiation dose. The second electrode 14 is placed in the interior space 10s which is located between the opening 12 and the wall area which is squarely faced from the opening 12. Moreover, a shield electrode 16 is interposed between the opening 12 and the second electrode 14 and electrostatically shields the second electrode 14 from the opening 12. |
