The present application relates generally to positron emission tomography (PET). It finds particular application in conjunction with energy calibration of a digital PET (DPET) detector and will be described with particular reference thereto. In one aspect, a difference spectrum is produced by finding a difference between a background radiation spectrum with no radioactive source loaded and a calibration source radiation spectrum with a radioactive source loaded. The difference spectrum may then be used to identify an energy peak.

The present application relates generally to positron emission tomography (PET). It finds particular application in conjunction with energy calibration of a digital PET (DPET) detector and will be described with particular reference thereto. In one aspect, a difference spectrum is produced by finding a difference between a background radiation spectrum with no radioactive source loaded and a calibration source radiation spectrum with a radioactive source loaded. The difference spectrum may then be used to identify an energy peak.

A computed tomography (CT) detector apparatus includes a plurality of detector arrays arranged in a ring, wherein for at least one array that includes a plurality of elements, an anode pixel pattern is non-uniform in a z-axis direction and a thickness of each element in the array is correspondingly non-uniform along the z-axis direction. A size of the anode pixels increases proportionally away from a center of the array, and a thickness of the elements increases away from the center of the array. The ratio of the thickness of the element to the size of the anode pixels is substantially the same over the array.

A mechanical linkage system of PET and CT/MRI and a linkage scanning method thereof are disclosed. According to an example of the disclosure, the mechanical linkage system includes a PET host, a CT/MRI host, a scanning bed, and a moving system. The PET host includes a PET detector installed in a PET detector fixing plate and configured to form a positron emission computed tomography image. The CT/MRI host has a larger aperture than the PET detector. A front end of the PET host and a front end of the CT/MRI host are oppositely disposed. The scanning bed is located to an end of the CT/MRI host. The moving system is connected with at least one of the PET host or the CT/MRI host and configured to move the PET detector into or out of a scanning field of view of the CT/MRI host.

An x-ray scanner includes an x-ray source producing a fan beam of x-rays, an x-ray detector array, a collimator, a second motor moving TDI detector arrays, and an x-ray processing unit. The detector array has the TDI arrays and detects x-rays from the source. The collimator disposed between the source and detector array defines slits to collimate the fan beam of x-rays into lateral beams with a height dimension the same as a height dimension of the TDI detector arrays. Either the collimator is fixed to the x-ray source or moves thereto. A first motor moves the collimator or the collimator and source together. The processing unit controls the motors, processes detection of the x-rays, and forms an image of an entity between the collimator and the detector array to have an intensity and contrast of the scanned image be maximized while an exposure dose for the entity is minimized.