Radiation meter null for 1cm depth dose equivalent measurement

摘要

PURPOSE:To measure a dose equivalent with good H1cm accuracy unless energy matches reference energy by providing two radiation detectors which have different radiation detection sensitivity-radiation energy characteristics, a radiation energy specification part, and an arithmetic part. CONSTITUTION:The radiation energy specification part 37 consists of amplifiers 26 and 27, a division part 35, and a decision part 36 and the energy of radiation 29 is specified according to the output-current ratio of two radiation detectors consisting of outside ionization chambers 5, inside ionization chambers 21, etc., to output an energy signal 36a. An arithmetic part 40 consists of a correction coefficient signal generation part 38 and a multiplication part 39. The generation part 38 stores a correction coefficient K1 as the function of the radiation energy, extracts the coefficient K1 corresponding to the radiation energy that the signal 36a shows from the correction coefficient storage contents, and outputs a correction coefficient signal 38a corresponding to the coefficient K1. A multiplication part 39 inputs a signal 38a and an amplification signal 37a and calculates a current value from a specific expression by using the coefficient K1 that the signal 38a shows and the ionization chamber output current value that a voltage 27a indicates, thereby outputting a measurement signal 39a corresponding to the found current value.