Patent Number: 
Section: claims

1. A gamma-ray imaging device, comprising:a scintillator which converts gamma rays into localized flashes of light;an image intensifier that collects a substantial fraction of the light from each flash produced by a single gamma-ray photon and produces an amplified flash of light;an optical system including a video camera to image each amplified flash onto an imaging detector that operates at a frame rate fast enough to allow spatial separation of most of the clusters of pixels that receive light from different gamma-ray interactions in the scintillator; anda processing unit programmed with instructions, the instructions when executed identify the clusters of pixels on the video camera associated with respective amplified flashes of individual gamma-ray photons and use the data from said cluster of pixels to perform a statistical estimation of a position where the corresponding gamma-ray photon interacted with the scintillator and the energy deposited in the interaction. 2. The gamma-ray detection device according to claim 1, wherein optical radiation of each amplified flash has a wavelength in a range from 100 nm to 1000 nm. 3. The gamma-ray detection device according to claim 1, wherein the scintillator comprises at least one of a columnar scintillator, a scintillation screen, or a monolithic scintillator. 4. The gamma-ray detection device according to claim 1, wherein the optical intensifier comprises:a photocathode made of at least one of Bialkali Antimonide, Multialkali Antimonide, Gallium-Arsenic-Phosphorus (GaAsP), or Gallium Arsenic (GaAs). 5. The gamma-ray detection device according to claim 4, wherein the optical intensifier further comprises a microchannel plate. 6. The gamma-ray detection device according to claim 1, wherein said processing unit is configured to:subtract a background image from the interaction image associated with the light from the different gamma-ray interactions;identify pixels of the interaction image that are above a certain threshold intensity value within a region-of-interest to define a cluster;calculate a centroid of the cluster; andgenerate a mean value of all the pixel that are located within the region-of-interest. 7. The gamma-ray detection device according to claim 1, wherein said processing unit is configured to:use a maximum-likelihood algorithm to estimate a vertical position, a horizontal position, said energy, and a depth of interaction of the gamma-rays in the scintillator. 8. The gamma-ray detection device according to claim 1, wherein a rear surface of the scintillator and a faceplate of the image intensifier are in direct contact with each other. 9. A system for capturing tomographic imaging data comprising:a plurality of aperture plates arranged around an inspection area, the plates having at least one pinhole; anda plurality of gamma-ray detection devices according to claim 1 arranged around the inspection area so that a plurality of respective optical axes of the plurality of gamma-ray detection devices intersect with the inspection area, the plurality of aperture plates arranged between the detection devices and the inspection area,wherein each of the plurality of gamma-ray detection devices are arranged at a different angle of orientation towards the inspection area. 10. The system for capturing tomographic imaging data according to claim 9, whereina distance from a front surface of the gamma-ray detection devices and the corresponding aperture plates is a range of 2 mm to 200 mm. 11. The gamma-ray detection device according to claim 1, wherein the intensifier comprises:a first image intensifier configured to intensify optical radiation from a first portion of a rear surface of the scintillator to generate first intensified optical radiation;a second image intensifier configured to intensify optical radiation from a second portion of the rear surface of the scintillator to generate second intensified optical radiation;a first and second optical coupling system configured to guide the first and second intensified optical radiation, respectively; anda first and second detector configured to detect the first and second intensified optical radiation and to generate first and second images, respectively, representing respective gamma-ray interactions in the scintillator. 12. The gamma-ray detection apparatus according to claim 11,wherein the first portion and the second portion of the rear surface of the scintillator are overlapping. 13. The gamma-ray detection apparatus according to claim 11, further comprising:a lens unit configured to split the optical radiation from the rear surface of the scintillator into optical radiation from a first portion and a second portion of the rear surface of the scintillator, respectively. 14. A method for gamma-ray imaging, comprising:in a scintillator, converting gamma rays into localized flashes of light;collecting a substantial fraction of the light from each flash produced by a single gamma-ray photon and producing an amplified flash of light with an image intensifier;imaging each amplified flash onto an imaging detector that operates at a frame rate fast enough to allow spatial separation of most of the clusters of pixels that receive light from different gamma-ray interactions in the scintillator; andidentifying the clusters of pixels on the video camera associated with respective amplified flashes of individual gamma-ray photons and using the data from said cluster of pixels to perform a statistical estimation of a position where the corresponding gamma-ray photon interacted with the scintillator and the energy deposited in the interaction. 15. The method according to claim 10, wherein said identifying further comprises:filtering digital data of the imaged amplified flashes to remove noise by a median filter; andidentifying the cluster of pixels by using a thresholding algorithm that is applied to the filtered digital image. 16. The method according to claim 14, wherein said identifying further comprises:storing calibration data representing reference clusters generated from a plurality of interaction depths and gamma-ray energies; andcomparing the cluster of pixels of the digital data image with the reference clusters by using a maximum-likelihood algorithm to estimate a horizontal position, a vertical position, a depth, and the energy of the interaction of the gamma-ray in the scintillator. 17. The method according to claim 14, wherein said method further comprises:calculating a kurtosis value for the cluster of pixels, whereinsaid step of processing the digital data image subjects the kurtosis value to the maximum-likelihood estimation. 18. The method according to claim 14, wherein in said step of processing the digital data image by the maximum-likelihood estimation, the maximum-likelihood estimation uses calibration data based on an eccentricity of the cluster.