Patent Number: 
Section: claims

1. A method of intervention by at least one operator in a radioactive zone, the method comprising the following steps:obtaining a digital model representing the three-dimensional topography of the radioactive zone;intervention of at least one operator in the radioactive zone, the intervention step comprising at least the following sub-steps:repeatedly, measuring an intensity of the radioactive radiation by a portable detector carried by the at least one operator, and determining the spatial coordinates of the portable detector at the time of measurement;recording in the digital model of a plurality of said measurements and the corresponding spatial coordinates;materialisation of the recorded measurements in an augmented reality device carried by the at least one operator, by a plurality of discrete holographic symbols, using the digital model, each holographic symbol indicating the intensity of the radioactive radiation of one of the recorded measurements, said symbol being materialized so as to appear to the at least one operator standing at a current position at the corresponding spatial coordinates where the at least one operator was standing when measuring the intensity of said recorded measurement at the sub-step of measuring the intensity of the radioactive radiation. 2. The method according to claim 1, wherein the augmented reality device comprises at least one helmet worn by the at least one operator, with a translucent display surface placed in front of the eyes of the at least one operator, wherein the holographic symbols are displayed on the display surface in such a way that the holographic symbols appear visible to the at least one operator at the corresponding determined spatial coordinates. 3. The method according to claim 1, wherein the obtaining step comprises a sub-step of recording images of the radioactive zone with at least one camera, and a sub-step of determining the digital model using the recorded images. 4. The method according to claim 3, wherein the obtaining step is carried out simultaneously with the intervention step, the digital model being progressively determined or enriched with the images recorded during the intervention step. 5. The method according to claim 1, wherein the recording of one of the measurements and the materialisation of said recorded measurement are triggered by the at least one operator, the said discrete holographic symbol materialising the intensity of the radioactive radiation measured by the portable detector at the moment of triggering. 6. The method according to claim 1, wherein the addition of a discrete holographic symbol to the augmented reality device is triggered when the intensity of the radioactive radiation measured by the portable detector is greater than a predetermined value. 7. The method according to claim 1, further comprising a step of recording in the digital model at least one of the elements associated with corresponding spatial coordinates selected from the group consisting of ALARA fallback zone and conventional non-nuclear risk;the intervention step comprising a sub-step of materialisation of the at least one element in the augmented reality device by a specific holographic symbol appearing visibly to the operator at the corresponding spatial coordinates. 8. The method according to claim 1, wherein the digital model is shared by several operators, each operator being equipped with an augmented reality device materialising the recorded measurements by a plurality of discrete holographic symbols using the digital model, each holographic symbol indicating the intensity of the radioactive radiation of one of the recorded measurements and being placed so as to appear visible to said operator at the corresponding spatial coordinates. 9. The method according to claim 8, wherein the operators all intervene in the radioactive zone during the intervention step, the intervention step comprising at least the following sub-steps:repeatedly, measuring an intensity of the radioactive radiation by the portable detector carried by each operator, and determining the spatial coordinates of the portable detector at the time of the measurement; andrecording in the shared digital model of a plurality of said measurements and the corresponding spatial coordinates. 10. The method according to claim 1, wherein at the sub-step of recording images of the radioactive area, the at least one camera is carried by the at least one operator. 11. A method of intervention by at least one operator in a radioactive zone, the method comprising the following steps:obtaining a digital model representing the three-dimensional topography of the radioactive zone;intervention of at least one operator in the radioactive zone, the intervention step comprising at least the following sub-steps:repeatedly, measuring an intensity of the radioactive radiation by a portable detector, and determining the spatial coordinates of the portable detector at the time of measurement;recording in the digital model of a plurality of said measurements and the corresponding spatial coordinates;materialisation of the recorded measurements in an augmented reality device carried by the at least one operator, by a plurality of discrete holographic symbols, using the digital model, each holographic symbol indicating the intensity of the radioactive radiation of one of the recorded measurements and being placed so as to appear visible to the at least one operator at the corresponding spatial coordinates; andrecording in the digital model at least one of the elements associated with corresponding spatial coordinates selected from the group consisting of ALARA fallback zone and conventional non-nuclear risk;the intervention step comprising a sub-step of materialisation of the at least one element in the augmented reality device by a specific holographic symbol appearing visibly to the operator at the corresponding spatial coordinates.