A radiation detector (11; 12) comprising a moisture protection structure, the radiation detector (11; 12) having a first area at a first side for receiving receiving radiation, a second side opposite to the first side attached to a supporting means, and a lateral side between a first perimeter delimiting the first area on the first side and a second perimeter delimiting a second area on the second side, the radiation detector (15; 11; 12) comprising: a scintillator having a first side and a second side opposite to the first side, the first side of the scintillator being arranged at the first area of the radiation detector (11; 12) for receiving the receiving radiation, and a photosensor coupled at the second side of the scintillator or in contact with the second side of the scintillator for receiving a converted receiving radiation from the scintillator and attached at the first mentioned second side of the radiation detector (11; 12) to the supporting means, the moisture protection structure comprising: at least one moisture-resistant layer deposited on the first area and the lateral side of the radiation detector (11; 12), a moisture-resistant cover arranged to cover the at least one moisture-resistant layer at the first side, wherein: the moisture-resistant cover and the at least one moisture-resistant layer are transparent for the radiation (RE;RR), and a pressurizing member (55;57;59) attached to the supporting means and comprising an elastic deformable material (40;42), the pressurizing member (55;57;59) being arranged for exerting a pressure on the moisture-resistant cover towards the second side for sealing the first side of the radiation detector (11; 12) against moisture penetration, characterized in that the pressurizing member (55;57;59), the elastic deformable material (40;42) and the moisture-resistant cover are arranged for allowing a free movement of the moisture-resistant cover in a direction in parallel to the first area of the radiation detector (11; 12). a scintillator having a first side and a second side opposite to the first side, the first side of the scintillator being arranged at the first area of the radiation detector (11; 12) for receiving the receiving radiation, and a photosensor coupled at the second side of the scintillator or in contact with the second side of the scintillator for receiving a converted receiving radiation from the scintillator and attached at the first mentioned second side of the radiation detector (11; 12) to the supporting means, the moisture protection structure comprising: at least one moisture-resistant layer deposited on the first area and the lateral side of the radiation detector (11; 12), a moisture-resistant cover arranged to cover the at least one moisture-resistant layer at the first side, wherein: the moisture-resistant cover and the at least one moisture-resistant layer are transparent for the radiation (RE;RR), and a pressurizing member (55;57;59) attached to the supporting means and comprising an elastic deformable material (40;42), the pressurizing member (55;57;59) being arranged for exerting a pressure on the moisture-resistant cover towards the second side for sealing the first side of the radiation detector (11; 12) against moisture penetration, characterized in that at least one moisture-resistant layer deposited on the first area and the lateral side of the radiation detector (11; 12), a moisture-resistant cover arranged to cover the at least one moisture-resistant layer at the first side, wherein: the moisture-resistant cover and the at least one moisture-resistant layer are transparent for the radiation (RE;RR), and a pressurizing member (55;57;59) attached to the supporting means and comprising an elastic deformable material (40;42), the pressurizing member (55;57;59) being arranged for exerting a pressure on the moisture-resistant cover towards the second side for sealing the first side of the radiation detector (11; 12) against moisture penetration, characterized in that the moisture-resistant cover and the at least one moisture-resistant layer are transparent for the radiation (RE;RR), and a pressurizing member (55;57;59) attached to the supporting means and comprising an elastic deformable material (40;42), the pressurizing member (55;57;59) being arranged for exerting a pressure on the moisture-resistant cover towards the second side for sealing the first side of the radiation detector (11; 12) against moisture penetration, characterized in that