Device for measuring radiation intensity of small sealed radiation source for cancer therapy

A radiation intensity measuring apparatus for small sealed radiation sources for cancer therapy, in which multiple radiation sources are held in a cartridge, and radiation intensity of the multiple radiation sources is measured while they are held by the cartridge, the apparatus comprising:

• holding means capable of holding the cartridge;
• radiation intensity measuring means for measuring intensity of radiation emitted from the multiple radiation sources packed in the cartridge in the state that the cartridge is held by the holding means;
• and
• moving means for moving the radiation intensity measuring means toward or away from the holding means,
• the holding means including:
• a radiation emitting part capable of emitting radiation emitted from the multiple radiation sources outside the holding means in the state that the cartridge is held by the holding means,
• the radiation intensity measuring means including:
• a sensor for measuring radiation intensity, and
• a shielding member provided for restricting radiation irradiated to the sensor;
• the shielding member being disposed to be positioned between the radiation emitting part of the holding means and the sensor in a measurement state where the radiation intensity measuring means is moved toward the radiation emitting part of the holding means,
• the shielding member being formed with a slit that penetrates between a face positioned on the side of the radiation emitting part of the holding means and a face positioned on the side of the sensor in the measurement state,
• the slit being formed so that width thereof is smaller than a wire diameter of the radiation source,
• the moving means being configured to be able to relatively move the radiation intensity measuring means along the direction orthogonal to an axial direction of each radiation source held by the cartridge in the measurement state.