Imaging systems, methods, and apparatus thereof

A single-photon emission computed tomography (SPECT) imaging system comprising:

• a detector including detecting modules arranged along a circumference direction of an imaging apparatus and configured to form an accommodation space;
• and
• a collimator configured to collimate radiation rays emitted from a subject reaching the detector, the collimator including collimating modules arranged along the circumference direction and configured to rotate around an axis of the accommodation space that is perpendicular to the circumference direction;
• wherein one of the collimating modules includes multiple collimating units in different configurations, the multiple collimating units are arranged along the circumference direction, each of the multiple collimating units is switched between an effective state and an invalid state via a rotation of the collimator around the axis of the accommodation space;
• the collimator includes a notch between two of the collimating modules which are adjacent to one another, a distance between the two of the collimating modules which are adjacent to one another is greater than a length of one of the detecting modules along the circumference direction, a projection of the notch along a radial direction covers the one detecting module, such that radiation rays passing through the notch are irradiated on the one detecting module.