| 摘要 |
PCT No. PCT/FI93/00577 Sec. 371 Date Nov. 19, 1996 Sec. 102(e) Date Nov. 19, 1996 PCT Filed Dec. 31, 1993 PCT Pub. No. WO95/18391 PCT Pub. Date Jul. 6, 1995The object of the invention is a method for determining the size and shape of the radiation field (11) of an X-ray machine automatically by means of a multielectrode ionization chamber (5). By means of the method relating to the invention both the dose and the size and shape of the radiation field can be measured separately so that the ratios of the currents of the electrodes (2, 3) located in different directions in the ionization chamber (5) to the current of the reference electrode (1) provide information on the size and shape of the field, and the sum of the currents is proportional to the dose. |
