Three-dimensional distribution measurement imaging device and image measurement method for the internal radiation of nuclear power plant concrete structures

摘要

The present invention relates to a three-dimensional distribution measuring imaging apparatus and an image measuring method for the internal radiation of a nuclear power plant concrete structure. To this end, the present invention comprises: a detector 100 for absorbing photons scattered by a scattering unit detector at an absorption unit detector and measuring energy and position information for these reactions to obtain a Compton image; It is connected to the detector 100 and receives electrical signals from a plurality of PMTs (Photomultiplier tubes) 120 through each channel, and forms the signal in the field programmable gate array (FPGA) 130 to form the peak height of the signal. An FPGA substrate 130 that measures and transmits and records a peak height value for each channel to the PC 170 in real time; A battery 160 for supplying power of 1000V and 12V voltage to the PMT and the FPGA substrate as a portable power supply device, respectively; A high voltage supply module 150 for converting a voltage of power connected from the battery 160 to the PMT into a high voltage; And a PC 170 that derives the gamma ray response position and energy in the detector through the data received from the FPGA substrate 130 and estimates the position of the radiation source through the Compton scattering equation. The present invention configured as described above relates to a measuring device for analyzing nuclides and measuring depth of radioactive substances existing inside a concrete structure, and in particular, using a location-sensitive large-area detector and Compton imaging technique, with only one measurement. The present invention relates to a device capable of three-dimensionally high-speed imaging of the distribution of radioactive substances such as hot spots in a wide inner area of a concrete structure of about 0.7 m × 0.3 m × 0.8 m.